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BJC/OR-1112 Facility Hazard Categorization/ Classification and Hazard Analysis Application Guide INTERNAL USE ONLY CAUTION This document has not been reviewed for patent and information control matters and should therefore be considered as an internal use only document. No external distribution is to be made with out prior approval of the appropriate Classification and Information Control Office.

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BJC/OR-1112

Facility Hazard Categorization/

Classification and Hazard Analysis

Application Guide

INTERNAL USE ONLY

CAUTION

This document has not been reviewed for patent and information control matters and should therefore be considered as an internal use only document. No external distribution is to be made with out prior approval of the appropriate Classification and Information Control Office.

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BJC/OR-1112

Facility Hazard Categorization/

Classification and Hazard Analysis

Application Guide

Date Issued�April 2002

Prepared by Westinghouse Safety Management Solutions LLC

Aiken, South Carolina under subcontract #23900-BA-ES029F

Prepared for the U.S. Department of Energy

Office of Environmental Management

BECHTEL JACOBS COMPANY LLC managing

Environmental Management Activities at the East Tennessee Technology Park

Oak Ridge Y-12 Plant Oak Ridge National Laboratory Paducah Gaseous Diffusion Plant Portsmouth Gaseous Diffusion Plant

under Contract DE-AC05-98OR22700 for the

U.S. DEPARTMENT OF ENERGY

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APPROVALS

Facility Hazard Categorization/

Classification and Hazard Analysis

Application Guide

This document is a new document. It applies to all BJC facilities when preparing EMHSs and EMHAs.

BJC/OR-1112

April 2002 Dennis O. Myers Date Nuclear Safety Supervisor Nuclear Facility Safety Organization Bechtel Jacobs Company LLC Bruce A. Wilson Date Manager Nuclear Facility Safety Organization Bechtel Jacobs Company LLC

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ACKNOWLEDGMENT

This document is the result of a team effort by the Bechtel Jacobs Company LLC (BJC) and Westinghouse Safety Management Solutions Mid-America (WSMS). The primary authors of this document were Mr. Kurt R. B. Menger and Ms. Michele L. Baker.

Mr. Menger has over thirty-two years of experience in operation of nuclear facilities and safety analysis. He has been recognized for his contributions in such areas as technical support, design and construction oversight, operational readiness coordination, facility startup functions, operating procedure development and implementation, training program development and presentation, and safety documentation development and interpretation. For the last six years, Mr. Menger has been heavily involved in hazard/accident analysis activities for the Savannah River Site and for other customers in the DOE Complex. He has taken the lead on several hazard analysis tasks and has played a key role in innovative approaches to hazard analysis. With a proven record in Plutonium processing facility operations, procedure development, and safety documentation development, Mr. Menger has been frequently sought as a consultant during the development of a number of facility Authorization Basis documents. Mr. Menger was appointed as the Manager of the Hazards Analysis Group at the WSMS Aiken, SC office in April 2001.

Ms. Baker has been a member of the WSMS Hazard Analysis Group for multiple years and in that time has authored various Safety Analysis documents. She has prepared Emergency Management Hazards Assessment reports for Oak Ridge facilities, as well as Hazard Analyses, Hazards Assessment Documents, and Supplemental Environmental Impact Statements for the Savannah River Site.

In addition to Mr. Menger and Ms. Baker, the following individuals provided significant input to the development of this guide:

Dennis O. Myers (BJC) Mike Taylor (BJC) Joe Little (BJC) Alvin Gwathney (BJC) Karen Balo (BJC) Mike Hitchler (WSMS) Doug Heal (WSMS) Jim McCormick (WSMS)

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CONTENTS

1. INTRODUCTION..................................................................................................................................... 1 1.1 PURPOSE ........................................................................................................................................ 1 1.2 INITIAL HAZARD CATEGORIZATION/CLASSIFICATION ..................................................... 1 1.3 HAZARD ANALYSIS..................................................................................................................... 2 1.4 FINAL HAZARD CATEGORIZATION ......................................................................................... 2 1.5 DOCUMENT OVERVIEW ............................................................................................................. 2

2. INITIAL HAZARD CATEGORIZATION/CLASSIFICATION.............................................................. 4 2.1 OVERVIEW..................................................................................................................................... 4 2.2 BASIC CONSIDERATIONS........................................................................................................... 4 2.3 OVERALL APPROACH ................................................................................................................. 6 2.4 HAZARD IDENTIFICATION......................................................................................................... 6

2.4.1 Facility Identification........................................................................................................... 7 2.4.2 Facility Description.............................................................................................................. 7

2.5 HAZARDS ....................................................................................................................................... 7 2.5.1 Preliminary Hazard Screening ............................................................................................. 8 2.5.2 Additional Considerations For Hazard Screening................................................................ 9

2.6 FACILITY CATEGORIZATION/CLASSIFICATION ................................................................. 10 2.6.1 Facility Categorization for Radiological Hazards .............................................................. 11 2.6.2 Facility Classification for Non-Radiological Hazards........................................................ 16

2.7 DETERMINATION OF CONSEQUENCES................................................................................. 19 2.7.1 Types of calculations ......................................................................................................... 20 2.7.2 Modification of consequence-based classification ............................................................. 21

2.8 DOCUMENTATION ..................................................................................................................... 24

3. HAZARD ANALYSIS ........................................................................................................................... 25 3.1 HAZARD IDENTIFICATION....................................................................................................... 26

3.1.1 Division of the Facility ...................................................................................................... 26 3.1.2 Facility Walkdowns ........................................................................................................... 26 3.1.3 Screening of Standard Industrial Hazards.......................................................................... 28 3.1.4 Results of Hazard Identification......................................................................................... 28

3.2 HAZARD EVALUATION............................................................................................................. 28 3.2.1 Initial Conditions ............................................................................................................... 29 3.2.2 Unmitigated Hazard Evaluation......................................................................................... 32 3.2.3 Mitigated Hazard Evaluation ............................................................................................. 36 3.2.4 Hazard Evaluation Output ................................................................................................. 38

4. FINAL HAZARD CATEGORIZATION................................................................................................ 39 4.1 INTRODUCTION.......................................................................................................................... 39 4.2 PROCESS....................................................................................................................................... 39 4.3 DOCUMENTATION ..................................................................................................................... 40

5. REFERENCES ....................................................................................................................................... 41

APPENDIX A ANALYSIS REFERENCES FOR HAZARD CATEGORIZATION/CLASSIFICATION .................................................................A-1

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APPENDIX B TABLES FOR HAZARD ANALYSIS ............................................................................ B-1

APPENDIX C HAZARDS SCREENING CRITERIA............................................................................. C-1

APPENDIX D INTEGRATED WORK PROCESS .................................................................................D-1

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1. INTRODUCTION

1.1 PURPOSE

Bechtel Jacobs Company LLC (BJC) has developed an integrated approach to the development of Safety Basis (SB) documentation. This approach is documented in application guides, which detail the development of major elements of the SB process. This integrated approach is designed to:

• Improve the overall quality of SB documentation by ensuring more uniformity of process and consistency of input parameters.

• Reduce the cost and time necessary for development of SB documents by standardizing the techniques used by the analysts, providing generic templates, and providing site specific information, as appropriate, thereby eliminating the need to �reinvent the wheel� for each document.

• Reducing the time necessary to update the documents by standardizing the process and ensure consistent flow of information throughout the process.

• Reduce the time necessary for review of the documents by Bechtel Jacobs Company LLC (BJC) management and the U.S. Department of Energy (DOE) by getting concurrence on methodology prior to development of SB documentation.

• Increase the involvement of operations in the development of SB documentation. This is considered a key in effectively implementing SB documents.

A flowchart summarizing the overall process is included as Figure D-1.

Specifically, this application guide presents the structure behind the development of the Initial Hazard Categorization and Classification, Hazard Analysis, and Final Hazard Categorization. The Initial Hazard Categorization and Classification provides a valuable measure of the hazards associated with a facility and is useful in developing a graded approach for the safety analysis required for the facility. The Hazard Analysis is a detailed evaluation of the hazards within a facility and identifies possible event scenarios along with the frequency, consequence and risk bin of the event. This information is the chief input into the control selection process. Final Hazard Categorization is performed based on the Unmitigated Hazard Evaluation (a portion of the Hazard Analysis) to re-examine the safety documentation needed for the facility.

1.2 INITIAL HAZARD CATEGORIZATION/CLASSIFICATION

The Facility Hazard Categorization/Classification section of the document presents a method for identifying hazards and categorizing/classifying facilities for safety analysis in accordance with 10 Code of Federal Regulations (CFR) 830 and subpart B and DOE Order 5480.23 (DOE 1992). Hazard identification is the process that selects hazards for consideration in facility categorization/classification. Facility categorization/classification reflects the relative magnitude of hazards in a facility, and is used in implementing a graded approach to facility safety analysis. The graded approach proportions the thoroughness and level of detail of safety analysis so it is appropriate to the magnitude of the hazard. The term �facility� is used

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throughout this document to include physical facilities, operational activities, processes, or experiments grouped together for safety analysis and documentation.

Each facility is defined and described in the Facility Description Document (FDD), which includes a detailed description of the facility and a maximum inventory of hazardous material. If the facility is identified as having only occupational hazards, it should be classified as Other Industrial and requires no further evaluation. However, if there are unique hazards identified, then a complete initial hazard categorization/classification must be performed in accordance with this application guide. This guidance document is based on DOE-STD-1027-92, Change Notice (CN) 1 (DOE 1997), DOE-EM-STD-5502-94 (DOE 1994a) and DOE-STD-1120-98 (DOE 1998), which augment requirements of the DOE Orders mentioned above.

1.3 HAZARD ANALYSIS

This portion of the document presents a method for conducting a Hazard Analysis (HA) consistent with guidance provided in Chapter 3 of DOE-STD-3009, CN 1 (DOE 2000). The HA provides a comprehensive assessment of facility hazards and/or accident scenarios that could produce undesirable consequences for BJC workers and public. The HA methodology includes hazard identification, screening for Standard Industrial Hazards (SIH), postulating release events, and risk binning of events based on frequency and consequence levels. The HA provides the core data from which potential follow-on activities, such as accident analysis, control selection, and emergency preparedness efforts are based.

An HA must be performed for a facility initially categorized as Category 3 or higher, or classified as Moderate or higher using the methodology described for initial hazard categorization/classification included in this application guide. If the facility was categorized/classified below these levels (i.e., Radiological, Low or Other Industrial), other less detailed forms of safety documentation are more appropriate [e.g., Auditable Safety Analysis (ASA), Health and Safety Plan (HASP)], and an HA is not required to be performed.

1.4 FINAL HAZARD CATEGORIZATION

Once the unmitigated HA is complete, the initial hazard categorization is re-evaluated. The consequences of the most bounding event are compared to dose thresholds given in DOE-STD-1027-92 to determine the final hazard categorization. If the facility remains categorized as a Category 3 facility or higher it will require accident analysis, control selection, and a mitigated HA (in addition to other required safety documentation). If the final hazard categorization determines that the facility can be downgraded to Radiological, Low, or Other Industrial, a Hazards Assessment Document (HAD) will be developed and submitted to DOE for approval. It is important to note that the final hazard categorization is for radiological hazards only; there is no final hazard classification for non-radiological hazards. Therefore, if a facility was initially classified as Moderate or higher, it will require accident analysis, control selection, etc., regardless of the outcome of the unmitigated HA.

1.5 DOCUMENT OVERVIEW

The purpose of this document is to provide the approach to be used for facility categorization for radiological hazards and facility classification for non-radiological hazards including energy sources; and to identify criteria, requirements, and instructions for implementing the basic considerations for hazard categorization and classification as well as hazard analysis. A description of allowable modifications for release fractions, segmentation, and special considerations, and guidance for making qualitative estimate to classify a

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facility for energy releases is also provided. References used for determining inventory-based categorization and classification are included in Appendix A.

In addition, this guide provides the recommended format and content for documenting hazard categorization/classification and for hazard analysis, and discusses the results of unmitigated hazard evaluation used in conducting final hazard categorization.

The entire SB document process (development and/or revision/periodic updates) is depicted in diagram form in Appendix D. By reviewing the process, inputs for each item can be determined as well as where the outputs are used. Figures D-2 and D-3 highlight the inputs necessary to perform the portions of the integrated work process addressed in this application guide (hazard categorization and/or classification and hazard analysis) as well as where the outputs from the hazard analysis are used.

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2. INITIAL HAZARD CATEGORIZATION/CLASSIFICATION

2.1 OVERVIEW

This portion of the document describes the method for performing an Initial Hazard Categorization/Classification. The categorization/classification process is broken down into two sections: hazard identification and facility classification.

In selecting hazards for facility categorization/classification, the hazard identification process separates occupational and unique hazards using screening criteria. If there are only occupational hazards, a facility is classified as an �Other Industrial� facility and no further safety analysis is required. Other Industrial facilities have only occupational hazards that are adequately controlled using established, standard industrial hygiene and safety management programs. These occupational hazards are not a factor in the facility categorization/classification method described in this document. Facility hazard categorization/classification is restricted to human safety issues. Environmental issues are controlled by other existing programs that utilize requirements, studies, permits, reviews, etc., which are separate from facility safety analysis. Unique hazards are evaluated by facility safety analysis to determine requirements for structures, systems, components, activities, or conditions that prevent accidents or mitigate consequences of accidents that could impact facility workers, other on-site persons, or the public.

Facility categorization is accomplished using an inventory-based method for the evaluation of radiological materials, and facility classification is accomplished using both inventory-based and consequence-based methods for the evaluation of non-radiological materials. In addition, qualitative considerations of the level of the hazard associated with energy sources will be made. Facility categorization and classification is done separately for radiological and non-radiological hazards, respectively. Facilities are categorized as Category 1, Category 2, Category 3, or Radiological for hazards characterized by ionizing radiation in accordance with DOE Order 5480.23, and the DOE Standards mentioned before (DOE 1992, DOE 1994a and DOE 1997). Facilities are also classified as �High,� �Moderate,� or �Low� for non-radiological hazards in accordance with DOE Order 5481.1B and DOE-EM-STD-5502-941. It should be noted that designation as a High hazard facility can be assigned only by DOE. Facilities not categorized/classified at any of these levels are classified as Other Industrial facilities.

2.2 BASIC CONSIDERATIONS

All facilities should be reviewed to separate occupational and unique hazards. Occupational hazards are those commonly encountered throughout industry, or are hazards present in quantities that are below the threshold quantities (TQs) prescribed in DOE guidance or reportable quantities (RQs) determined in the Code of Federal Regulations (CFR). Occupational hazards are adequately controlled by standard industrial safety provisions, which include training, procedures, warning signs and labels, protective clothing and equipment, workplace surveillance, and employee health monitoring programs. Facilities having only occupational hazards are classified as Other Industrial facilities.

1 Although these references have been cancelled, replacement guides have not been generated. These documents specify standard current practices across the DOE complex, and; therefore, will be referenced in this guidance document.

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Unique hazards are of interest in facility safety analysis. The hazard identification process identifies the unique hazards that require further hazard evaluation and possibly accident analysis. Detailed hazard and accident analysis, which considers accident initiation, scenario progression, and system and human response to accident events, is beyond the scope of hazard identification and facility categorization/classification. These are the subjects of facility safety analysis.

Facility categorization/classification involves an inventory-based approach for radiological materials, and an inventory-based approach combined with a consequence-based evaluation for non-radiological materials. The facility hazard categorization/classification is a measure of the potential severity of impacts of releasing identified hazardous materials. To determine facility categorization the inventory of each identified radiological material is compared to categorization criteria established by the DOE. This inventory-based method of facility categorization does not require quantitative determination of release rates and dispersion of airborne hazardous materials, nor does it require quantitative determination of the probability of events that could release hazardous material. The inventory-based method does not take credit for accident prevention or mitigating actions; however, adjustments to selected categorization criteria are allowed to apply realistic release fractions when different from those used as the basis for the criteria. Also, it is permissible to take credit for facility segmentation. According to DOE-STD-1027-92, “The concept of independent facility segments should be applied where facility features preclude bringing material together or causing harmful interaction from a common severe phenomenon.” For facility classification, the inventory of each non-radiological material is first compared to classification criteria established by the DOE. If the inventory exceeds the criteria, the non-radiological material must be evaluated further using a consequence-based analysis.

Unique hazards included in hazard identification and facility categorization/classification are:

1. Radiological hazards associated with ionizing radiation. These include naturally radioactive materials, �man-made� radioisotopes, radioactive surface contamination, radioactive waste, and ionizing radiation from fission reactions or inadvertent nuclear criticality.

2. Non-radiological hazards associated with dangerous properties of materials. These include materials that are toxic by human contact, ingestion, or inhalation; carcinogens; and biohazards. Also included are materials that are gases, or which become gases at ambient conditions, which could pose a threat of asphyxiation by displacement of breathing air. Materials characterized by flammability, self-reaction, or explosive tendencies are included. Incompatible materials normally separated, which produce reaction products with the hazardous characteristics just described, should be included in this category unless segmentation precludes mixing. Also, combustion products from accidental fires should be included in this category.

3. Non-radiological hazards associated with energy sources. Energy sources should be included if they could significantly adversely impact persons within the facility or beyond facility boundaries. Energy sources include electrical energy, kinetic energy, pressurized containers and equipment, potential energy, and devices that can produce either ionizing or non-ionizing radiation by �on-off� modes (lasers, particle accelerators, and X-ray machines). Qualitative considerations are used in facility classification for energy releases. It is necessary to estimate the severity of energy releases considering the location of potentially impacted persons. The locations of interest are the facility where the hazard is located, on-site locations beyond the facility boundary, and off-site locations.

Hazard identification and facility classification should be documented in a standardized format. All hazards in some facilities might be determined by the hazard screening to be occupational hazards. In these cases the facility is classified as an Other Industrial facility. Hazard identification documentation should be prepared for Other Industrial facilities to provide a record of the hazards considered in hazard screening and to record the outcome of hazard screening. Those facilities that have unique hazards should be

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categorized/classified as previously described, and documentation should record the categorization/classification and the basis for the results.

2.3 OVERALL APPROACH

Hazard identification and facility categorization/classification should typically be accomplished by performing the following tasks in the order listed. Details are provided in later sections.

• Review the FDD and other documents that describe the facility and associated processes. Consult operations and engineering personnel to determine the processes and functions performed in the facility. Determine the systems and subsystems to be evaluated in organizing the information about hazards and facility classification.

• Visit (�walk-down�) the facility and interview appropriate operations and engineering personnel to determine which hazards are present. Use the screening criteria discussed in the �Hazard Screening� section to separate occupational and unique hazards. Record information about the facility and hazards. Information should identify the facility and the amount and form of the hazards.

• If the facility contains only occupational hazards, classify the facility as an �Other Industrial� facility and document the result and basis for the determination.

For facilities with unique hazards, use information about the hazards as described in the following three steps to categorize/classify the facility. Categorize/classify the facility for both radiological and non-radiological hazards, respectively. Appendix A provides convenient reference sources that may be used to perform these tasks.

• Compare the maximum allowable amount of each radionuclide with its RQ and TQ to determine the inventory-based categorization of the facility for radiological hazards. If appropriate, adjust only the TQ for Category 2 categorization by applying alternative release fractions. Alternative release fractions are not to be used to adjust Category 3 TQs. Segmentation and special considerations may also be used in facility categorization for radiological hazards. Adjustments, segmentation, the treatment of mixtures and/or multiple radioisotopes, and special considerations are described in subsequent sections.

• Perform consequence-based evaluation for the hazardous chemicals that exceed their respective RQs. Segmentation, the treatment of mixtures and/or multiple chemicals, and special considerations are described in subsequent sections.

• Identify unique hazards associated with energy sources and classify the facility based on judgment and qualitative estimates of the health and safety consequences if the energy is released.

• Prepare documentation of the hazard identification and facility classification activities according to requirements given in this guidance document.

2.4 HAZARD IDENTIFICATION

Hazard identification is a structured process for identifying radioactive materials, hazardous chemicals, and sources of energy that are to be used in facility hazard classification. The process involves (a) identifying the facility or activity of interest; (b) dividing the facility or activity into systems, subsystems, or phases; (c)

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recognizing hazards, (d) separating occupational and unique hazards, and (e) recording data about the unique hazards for use in facility hazard classification.

The key objective of hazard identification is the separation of occupational hazards and unique hazards. This is accomplished by first reviewing materials, energy sources, and operating conditions associated with the facility to determine hazards that are present. These hazards are then compared with screening criteria to determine if the hazards are occupational hazards or unique hazards. If there are only occupational hazards in a facility, the facility is classified as an Other Industrial facility. No further safety analysis is necessary, and appropriate documentation is prepared to record that this decision has been taken. Information is recorded about unique hazards for use in facility classification.

2.4.1 Facility Identification

The hazard identification process should clearly define the project, facility, or activity for which the hazards are examined. The location, functions, boundaries, and interfaces should be described so there is no uncertainty about the identity of the facility for which hazards are reviewed. This information should be documented in the FDD.

2.4.2 Facility Description

Information necessary to describe a facility may be obtained from the FDD. If additional information is needed, it can be obtained by (a) visiting the facility of interest; (b) discussions with persons who will be operating the facility; (c) discussions with designers, safety personnel, and others familiar with the functional requirements of the facility; and (d) review of applicable design documents, procurement specifications, operating and maintenance procedures.

The facility of interest should be divided into structures, systems, subsystems, and phases appropriate for the organized presentation of data about hazards. The organization should be designed to assist a person unfamiliar with the facility or activity in searching, retrieving, or using the data for activities related to facility safety analysis. As an example, an enriched uranium facility which converts UF6 to UF4 could be divided into the following systems: feed autoclave, sampling autoclave, fluorine supply, hydrogen supply, reactor, cold baths/chemical traps, and the potassium hydroxide supply. Avoid dividing a facility to the component level of detail (e.g., tanks, pumps, piping, etc.) because unnecessary complexity may compromise the usefulness of information.

It may be desirable to divide a large facility into segments and evaluate the hazards in each segment independently. This can be an efficient way to evaluate a large facility containing independent processes with different hazards. Caution is advised to ensure the segments are actually independent before evaluating segments independently. To be independent, failures in one segment must not propagate into another segment and accumulative release of hazards must not occur from multiple segments due to a common event (e.g., a fire that starts in one segment cannot propagate to another segment).

2.5 HAZARDS

Materials, energy sources, and operating conditions should be considered as hazards if they satisfy any of the criteria listed below. Hazards to be considered include:

• Any element, compound, or hazardous waste appearing in Table 302.4 of 40 CFR 302.

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• Any material listed in 29 CFR 1910.119, Appendix A, �List of Highly Hazardous Chemicals, Toxics, and Reactives.�

• Any material listed in 40 CFR 355, �Emergency Planning and Notification.�

• Any radioactive substance.

• Any known carcinogen: Go to http://hmweb.ctd.ornl.gov/complete_carcinogen.html.

• Any gas that is denser than air and could cause asphyxiation.

• Any other material that experience or knowledge indicates to have hazardous characteristics such as toxicity, flammability, explosiveness, reactivity, or corrosiveness. Reaction products not normally present in the facility, but which could result from inadvertent mixing of incompatible materials should be included. Intermediate substances that are produced and subsequently consumed in processes in the facility should be included. Hazardous characteristics of combustion products should be considered.

• Energy sources, if loss of control might impact facility workers, other on-site persons, or the public. The types of energy included are electrical, kinetic (e.g., flywheels), pressurized containers and equipment, and potential energy associated with elevated mass. Lasers, particle accelerators, and X-ray equipment should be included as hazards.

2.5.1 Preliminary Hazard Screening

The first step of the hazard identification activity is Preliminary Hazard Screening (PHS), a straightforward sorting process used to determine if more detailed hazard screening analysis is needed. Only those facilities or processes that are either Other Industrial in nature or obviously benign are screened out during the PHS process. If there is any unresolved question as to the magnitude of the hazards, the facility or process is passed on to the more detailed facility classification step. The PHS step may be bypassed if it is extremely likely that the hazard level will be at least Low, if an inappropriate effort would be required to conduct the PHS evaluation, or it is apparent that a more detailed analysis is needed.

A recommended PHS worksheet is presented in Attachment G of BJC-NS-1002. The �Action Basis� column should include information regarding the maximum anticipated inventory of a material and the form (e.g., liquid, gas, solid) of the material. It is important to indicate the physical form of a hazardous material. For example, massive shapes of uranium are not easily combusted because of the small surface to mass ratio, but fine machine turnings of uranium (with large surface to mass ratio) self-ignite in air. If a hazardous substance is in a solution (or mixture), its fraction, or percentage, in the solution (or mixture) should be specified.

Hazard screening criteria are based on: 1) whether the inventory of a material is (a) less than the TQs in DOE-STD-1027-92 or the RQ in Appendix B of 40 CFR 302 for radiological materials, or (b) less than the RQ in Table 302.4 from 40 CFR 302 for toxic materials; 2) whether industry standards are satisfied; or 3) whether knowledge or experience indicates the materials are hazardous. Values of various chemical and physical properties for a material can be found in handbooks or manuals [e.g., National Institute of Occupational Safety and Health (NIOSH) 1994, Perry, R.H. and Chilton, C.H. 1973, and Sax, N.I. and R.J. Lewis 1992] or in Material Safety Data Sheets (MSDS). National Fire Protection Association (NFPA) Standard 49 (NFPA 1991) is useful in separating occupational and unique hazards. In addition, chemicals should be screened against the RQs and Threshold Planning Quantities (TPQs) of 40 CRF 355, the TQs of 29 CFR 1910.119, and the TQs of 40 CFR 68. If the inventory of the facility is above any of these screening quantities, develop programs in accordance with the CFR(s) in which the screening quantities were exceeded.

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Screening criteria for hazardous energy sources are also included in the PHS worksheet. These criteria are based on quantitative levels, satisfaction of industry standards, qualitative evaluations, experience, and judgment. These criteria are intended to screen out from consideration those energy sources that could not benefit significantly from facility safety analysis. Routine energy sources that are adequately controlled by industrial safety programs are eliminated from further evaluation.

2.5.2 Additional Considerations For Hazard Screening

The RQs were selected as screening criteria to establish the boundary between Low hazard and Other Industrial facilities. If an RQ is not available for a known toxic chemical or combustion product [e.g., a material for which the NIOSH Pocket Guide to Chemical Hazards lists as Immediately Dangerous to Life and Health (IDLH)], the analyst may choose to proceed with the consequence-based evaluation or determine a substitute RQ. The methodology for determining a substitute RQ is provided in Attachment 4 to Appendix A.

Consistent with the guidance in DOE-STD-5502-94 and DOE-STD-1027-92 for considering the simultaneous release of multiple radionuclides, the combined effects associated with the simultaneous release of multiple hazardous materials (e.g., mixtures) should also be considered. During the initial hazard screening, credit should not be taken for facility segmentation unless it is obviously appropriate.

2.5.2.1 Nature of process

Consideration for the screening of material for categorization/classification purposes due to nature of process is allowed. If hazardous material cannot be released in an unmitigated event based on its form, location, dispersability, and interaction with other materials, it can be excluded from the inventory evaluated for hazard categorization/classification. For facilities with inventories containing fissile material, credit may be taken if nature of process precludes the potential for criticality. In this case the standard TQs from DOE-STD-1027 should be used as opposed to the criticality mass limits. It should be noted, though, that this material should be listed in the inventory included in the FDD, regardless of availability for release.

2.5.2.2 Treatment of mixtures/multiple chemicals

When two or more toxic substances are present and could be released simultaneously as a result of a credible accident, their combined effect should be considered. It should be noted that for some facilities with hazardous materials that are distributed in small quantities in separate areas of the facility, or in dilute concentrations throughout the facility, a simultaneous release of the total inventory is not feasible. Examples of such facilities may be burial sites or storage facilities. If release of the total inventory is not assumed, the documentation must indicate the maximum expected amount of hazardous material that could be released in one event and the rationale for considering less than the total inventory.

When considering the release of multiple materials, without information to the contrary, the effects of the different materials should be considered as additive. That is, if the sum of the following fractions, M1/RQ1+M2/RQ2+ . . . +Mn/RQn exceeds 1.0, then the limit of the mixture should be considered as being exceeded. �M� indicates the mass of the toxic material being evaluated, and RQ, the corresponding limit. It may be unreasonable to determine ratios and use the sum-of-ratios approach for facilities with a large number of hazardous chemicals. Facilities that may have dozens or hundreds of chemicals include storage facilities and waste facilities. Hazardous chemicals present in amounts nominally less than approximately 10% of their RQ values may be excluded from the summation in such facilities. Exceptions to this approach may be taken when there is good reason to believe that the chief effects of the different harmful substances are not in fact additive, but independent, as when purely local effects on different organs of the body are produced by the various components of the mixture. Consideration of synergistic action would normally be considered outside the scope of hazard

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screening. However, if a mixture of hazardous chemicals has known synergistic chemicals that can be identified and characterized by inspection by an industrial hygiene staff member, synergism should be considered.

2.5.2.3 Facility segmentation/consideration of simultaneous releases of multiple hazards

When considering the simultaneous release of multiple hazardous materials, an evaluation may indicate that facility segmentation is appropriate and that the simultaneous release of all the hazards is not credible. If facility segmentation is appropriate, an evaluation of the sum of the RQ fractions should only consider those materials present in the same facility segment. A consideration of credible accidents is normally required to determine whether multiple hazards can be released from a credible accident. This scenario development and analysis is beyond the scope of the PHS. Therefore, unless it is obviously inappropriate, the PHS should normally consider the simultaneous release of all hazardous materials present in a facility or facility segment.

2.5.2.4 Use of release fractions

The RQs from Table 302.4 of 40 CFR 302 are based on the standard physical characteristics of materials at ambient conditions. If a material is present in an unusual form (e.g., a material that is normally considered to be a liquid is absorbed in a powder), it is appropriate to compare the material at risk (MAR) to the RQ by considering the release fraction.

The release fraction should be used to determine the magnitude of the MAR by multiplying the total inventory of a toxic material by the ratio of the release fraction of the material in its actual form to the release fraction appropriate for the typical form (e.g.; gas or liquid) for the material. The MAR should then be compared with the RQ for each material.

For example, if a gas is present in an aqueous semivolatile solution, it may be reasonable to assume the release fraction of the gas is 0.5 instead of the more typical 1.0 release fraction for a gas. The 0.5 and 1.0 release fractions are based on the release fraction information provided in Attachment 1 of DOE-STD-1027-92. Therefore, the MAR to be compared with the RQ would be (0.5)/(1.0)• (MAR).

2.5.2.5 Exposure duration

A 24-hr maximum exposure duration is assumed in DOE-STD-1027-92. Therefore, the MAR should be based on the maximum amount of material released over 24 hrs. To determine the amount released, use the total amount of MAR if the release duration is less than 24 hrs, but if the release occurs over a longer time, estimate the amount released in a 24-hr period.

An example of a facility where this may be an important consideration is an in situ vitrification process. In situ vitrification typically occurs slowly over a period of days, and the release of toxic substances would be gradual. The MAR to be compared with RQ values should be obtained by estimating the maximum amount to be released in a 24-hr period.

2.6 FACILITY CATEGORIZATION/CLASSIFICATION

Facility categorization/classification considers radiological and non-radiological hazards separately. In decreasing order of importance to facility safety, facilities are categorized for radiological hazards as Category 1, Category 2, Category 3, or Radiological. Similarly, facilities are classified for non-radiological hazards as High, Moderate, or Low. If a facility does not qualify for one of these categorizations or classifications it is classified as Other Industrial.

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Facility radiological hazard categorization consists of determining the inventory-based categorization for each radioactive material identified using the process. Non-radiological hazards (e.g., toxic materials, energy sources, reactive materials) that were not screened out during the hazard screening process are further analyzed using a consequence-based evaluation to determine the facility classification. Within restrictions described later, the categorization/classification may then be modified as necessary to take credit for segmentation or to reflect release fractions that are different from the release fraction upon which criteria are based. An example of the resulting facility categorization/classification might be �Category 2 for radiological hazards and Low for non-radiological hazards.� If the example had only occupational non-radiological hazards, the example facility categorization/classification would be �Category 2 for radiological hazards with negligible non-radiological hazards.� The term Other Industrial Facility should only be used when both radiological and non-radiological type hazards in the facility are determined to be occupational hazards using criteria in this document.

2.6.1 Facility Categorization for Radiological Hazards

2.6.1.1 Process

The first step of facility categorization for radiological hazards is to compare the inventory of radionuclides to the RQs given in Appendix B of 40 CFR 302 and the TQs in Table A.1 of DOE-STD-1027-92. The method for determining inventory amounts is explained in earlier sections addressing hazard identification. The inventory-based categorization is determined based on the comparison of inventory, RQ and TQ values and using the criteria described in Sect. 2.6.1.2.

The inventory-based categorization should next be compared with results of previous hazard categorization activities for similar facilities. Determine if the inventory-based categorization is consistent with experience in categorizing other facilities. Determine, based on technical expertise, if the results are consistent with what is expected. For those facilities with questionable inventory-based categorization, use techniques described in Sect. 2.6.1.3 in order to modify the inventory-based classification.

Select either the inventory-based categorization or the modified inventory-based categorization for each radiological hazard.

Hazard identification and facility categorization documentation should record the basis for the facility categorization for radiological hazards.

2.6.1.2 Criteria

The radionuclide inventory is compared to criteria listed below to categorize a facility for radiological hazards. Inventory refers to the maximum amount of a radionuclide expected to be present in a facility at any time. Figure D-2 in Appendix D provides a flowchart for the inventory-based categorization of radiological hazards.

• A facility is Category 1 if it is a Category A nuclear reactor with steady-state power level greater that 20 MW(t), or it is designated Category 1 by the Cognizant Secretarial Officer or the designated representative.

• If the inventory is equal to or greater than the Category 2 TQ in Table A.1 from Attachment 1, DOE-STD-1027-92, then the facility is Category 2 unless it is Category 1.

• If the inventory is equal to or greater that the Category 3 TQ in Table A.1 from Attachment 1, DOE-STD-1027-92, but less than the Category 2 TQ, then the facility is Category 3.

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• If the inventory is equal to or greater than the RQ in 40 CFR 302.4, but less than the Category 3 TQ, then the facility is Radiological.

In addition to the above criteria, facilities are Category 2 (or greater) if the inventory of fissionable radionuclides 233U, 235U, or 239Pu is equal to or greater than 500, 700, or 450 g, respectively, unless segmentation or the nature of the process precludes the potential for a criticality. For combinations of 233U, 235U, and 239Pu, the threshold for Category 2 is 450 g. The site Nuclear Criticality Safety organization should be consulted for guidance on other fissionable materials (e.g., 243Cm). If there is no potential for criticality due to segmentation or the nature of the process, the basis for this conclusion should be included in the documented basis for facility categorization (HAD, see Section 4.3).

The combined hazard associated with �n� different radionuclides (whether elements or isotopes) is determined by evaluating the sum of the ratios of the individual radionuclide inventories and their RQs. Based on the radiological material inventory, a facility is an Other Industrial facility if the following condition is true:

M1/RQ1 + M2/RQ2 + M3/RQ3 + ...Mn/RQn < 1.0,(1)

Mn is the inventory of radionuclide �n� and RQn is the reportable quantity of radionuclide �n� from 40 CFR 302.4. The inventory is the maximum amount of material that could be present at the location of interest. It is not the amount that could be released.

For a mixture of radionuclides, or more than one isotope of the same element, in which equation (1) gives a value greater than one, the ratios of inventory to appropriate TQ should be combined to determine the category of the mixture. With �Cat3TQ� being the Category 3 TQ, the combination in equation (2) below is evaluated:

M1/Cat3TQ1 + M2/Cat3TQ2 + M3/Cat3TQ3 + ...Mn/Cat3TQn < 1.0 (2)

If the sum in equation (2) is less than one, the facility should be categorized a Radiological facility, given that the combination in equation (1) is equal to or greater than one. If the combination is equal to or greater than one, the following equation should be evaluated:

M1/Cat2TQ1 + M2/Cat2TQ2 + M3/Cat2TQ3 + ...Mn/Cat2TQn < 1.0 (3)

If the sum in equation (3) is less than one, the facility should be classified as Category 3 given that equation (2) is equal to or greater than one. If the sum in equation 3 is equal to or greater than one, the facility should be classified as Category 2, unless there is reason to classify it as Category 1. Additional considerations regarding the summation of radionuclides for Category 2 facilities can be found in DOE-STD-1027-92. These considerations are that (1) it is necessary to consult the individual threshold values only if an isotope is being isolated and collected for some purpose and (2) facilities are considered category 2 if the potential for criticality exists in the storage arrays and processing means used. See the standard for a more detailed discussion on these considerations.

2.6.1.3 Modification of inventory-based categorization

There are two basic ways to modify the inventory-based categorization: (1) adjust the TQ for a different release fraction, and (2) take credit for segmentation. Each of these is described below. Categorization is based on an unmitigated release of available radionuclides. This means categorization may consider material quantity, form, location, dispersibility, and interaction with available energy sources. However, categorization may not take credit for safety devices whose function is to prevent or mitigate consequences of accidents.

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Adjustment of Category 2 threshold quantities for alternative release fractions

The TQs given in DOE-STD-1027-92 are intended to be generally conservative for a broad range of possible situations and may be used directly for determination as to whether a facility exceeds Category 2. In addition, adjustments of Category 2 TQs are explicitly described in DOE-STD-1027-92 for situations where the credible release fractions can be shown to be significantly different than these values based on physical and chemical form and available dispersive energy. The basis for using alternate release fractions, and therefore, alternate TQs, must be provided in the hazard categorization documentation and further supported in the Hazards Analysis. Table 1 lists the release fractions assumed by DOE as a simplified means of providing conservative estimates of the amount of material released in establishing Category 2 TQ values in DOE-STD-1027-92.

Table 1. Release fractions assumed by DOE for Category 2 threshold quantities (from page A-9, Attachment 1, DOE-STD-1027-92)

Material Release Fraction Gases (tritium, krypton, xenon, argon, radon, chlorine)

1.0

Highly Volatile or Combustible (phosphorus, sulfur, potassium, iodine, sodium, bromine)

0.5

Semi Volatile (selenium, mercury, cesium, polonium, tellurium, ruthenium, carbon)

10-2

Solid, Powder, or Liquid (all materials not listed above)

10-3

For example, DOE based the TQ for solid uranium on a release fraction fi = 10-3. If the physical and chemical characteristics of the release phenomena can be shown to involve an alternative release fraction, fa = 10-4, then it is permissible to adjust the TQ in Table A.1 from Attachment 1, DOE-STD-1027-92 as follows:

Cat2TQadjusted = Cat2TQSTD-1027-92 × fi/fa (4)

Cat2TQadjusted = Cat2TQSTD-1027-92 × 10 (5)

Alternative release fractions may be determined by methods described in Airborne Release Fractions/Rates and Respirable Fractions for Nonreactor Nuclear Facilities, (DOE 1994b). It is noted that release fractions listed in Table 1 are not to be used for any other purpose than to adjust Category 2 TQs listed in Table A.1 from Attachment 1, DOE-STD-1027-92. It should also be noted that if the default release fractions are known to be non-conservative for a particular scenario (e.g., burning uranium with water present), more conservative release fractions should be applied.

Segmentation

Within a given facility there may be a wide variety of independent, co-located operations. The concept of segmentation is used in facility hazard classification to avoid placing inappropriate or excessive requirements on simple co-located operations. For segments to be independent, a single initiating event, such as an earthquake, must not result in a release of inventory from two or more segments. It is not necessary to include the total inventory of radioactive and special nuclear materials in determining a facility�s inventory when segments can be shown to be independent. The concept of independent segments should be applied where facility features (not safety features) preclude bringing material together or causing harmful interaction from a common severe phenomenon. When segmentation is used to modify the inventory-based categorization, justification of the independence of the segments should be included in the documentation of hazard

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identification and facility categorization. The concept of segmentation may be applied to facilities that might be initially categorized as Category 2 or 3 without segmentation. That is, an initial facility categorization of Category 2 might become Category 3 or Radiological, or an initial categorization of Category 3 might become Radiological by applying segmentation.

Segmentation may be applied to categorize facilities for criticality hazards. To accomplish this, the inventory, location, and distribution of fissionable materials must be known. If it can be shown that facility features preclude bringing sufficient material together for criticality, segmentation may be used to determine facility categorization. For segmentation to be applied, it is also necessary to show that a common severe phenomenon (e.g., a seismically induced building fire) will not cause interaction of fissionable materials in a manner that could result in criticality.

2.6.1.4 Special considerations for radiological hazards

It is recognized that broad application of general criteria might result in unrealistic categorization of some facilities. There may be unique situations that require special considerations for meaningful hazard evaluation and facility categorization. The following sections discuss special considerations where it is difficult or inappropriate to apply inventory-based criteria.

Effect of physical and chemical conditions on criticality

The facility is Category 2 (unless otherwise designated Category 1) if ≥500 g of 233U, ≥700 g of 235U, ≥450 g of 239Pu, or ≥450 g of any combination of these isotopes are present and there is potential for criticality, and the record should indicate this is the basis. If other fissionable nuclides (e.g., 243Cm) are present, consult the site Nuclear Criticality Safety office for information about critical mass, and categorize the facility as Category 2 whenever there is potential for criticality. When physical/chemical conditions, segmentation, or unique features of the process indicate that criticality is not physically possible or credible, even though these amounts are exceeded, then it is necessary to record the basis for determining that there is no potential for criticality.

Criticality may be incredible because of the nature of the process, or because of the combination of natural nuclear properties and the physical/chemical form of fissionable materials. For example, a storage facility might contain a large quantity of depleted uranium billets. A small fraction of depleted uranium is 235U, and the total amount of 235U might exceed the 700 g that require that the facility be Category 2. However, nuclear properties and the physical condition of the uranium make criticality physically impossible. In this case, DOE-STD-1027-92 has allowed categorization to be based on TQs of 1.9 × 106 g and 1.1 × 108 g of 235U for Category 3 and 2, respectively. It should be noted that the other isotopes (e.g., 238U and 232U) must also be considered in establishing the hazard categorization.

Sealed sources

Some facilities contain sealed sources that are used for checking, testing, or calibrating instruments or to provide radiation fields for specific, non-process purposes. DOE-STD-1027-92 states, �Sealed radioactive sources that are engineered to pass the special form testing specified by the U.S. Department of Transportation (DOT) in 49 CFR 173.469 or testing specified by American National Standards Institute (ANSI) N43.6, �Sealed Radioactive Sources, Categorization,� may be excluded from summation of a facility�s radioactive inventory.� DOE-STD-1027-92 also requires that such facilities �...must have in place a source control policy that complies with DOE Notice 5400.9, �Sealed Source Control Policy,� and the source control policy specified in Article 431 of the DOE Radiological Control Manual.� This is interpreted to mean that facilities need not be categorized as Category 3 or higher if sealed sources meet these conditions, or are properly stored.

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Facilities with sealed sources, in quantities that exceed the RQs, which satisfy the above-mentioned DOT or ANSI and DOE testing requirements should be categorized as Radiological facilities. If sealed sources do not meet these requirements, Radiological categorization may be requested (based on available data, use, leak testing, etc.) in writing to the site Facility Safety organization. In either case, source control policy meeting DOE N-5400.9 and the Radiological Control Manual is essential to the Radiological categorization. Otherwise, the source radionuclide inventory is compared with RQ and TQ values to determine the inventory-based facility categorization.

It is important to note that even though the inventory of the sources does not need to be explicitly considered in the facility categorization, the material may still be a hazard. More specifically, if the source contains a fissile radionuclide, it must still be considered for Nuclear Criticality Safety purposes.

Surface contamination

DOE Order 5480.11 and 10 CFR 835 establish requirements for protection of workers from ionizing radiation in occupational settings. These standards establish controls and set exposure limits for direct radiation, ingestion and inhalation of radioactive substances, and contact with surface radioactive contamination. Radiological Areas are required where work surface contamination exceeds the established levels. Appendix A contains discussion about these levels, taken from Surface Radioactivity Guides from Attachment 2 of DOE Order 5480.11.

The measured amount of surface contamination should be compared with the levels of fixed, removable, or both fixed and removable surface contamination in the Surface Radioactivity Guides. If surface radioactivity measurements are greater than those values, the facility should be categorized as Radiological. Facilities with measured radioactivity equal to or less than values in the Surface Radioactivity Guides may be considered Other Industrial facilities unless the non-radiological hazards require a higher classification.

Radioactive waste

Radioactive waste is found in waste storage or disposal areas, burial sites, tanks containing liquid or sludge, residual non-fixed contamination, or in areas undergoing active remediation. For such waste facilities, determine the inventory or administrative limits for radionuclides. If the inventory or limit is known with reasonable accuracy, determine the category by applying the inventory-based categorization criteria. If this results in an unreasonably high categorization, modification can be made as described in the next paragraph. If the inventory is not known and cannot in a practical sense be known with reasonable accuracy or if the inventory is currently not limited administratively, consult Facility Safety for assistance in determining the facility categorization. When categorizing waste facilities, thoroughly document the analysis and assumptions upon which the categorization is based.

Waste facilities often consist of radionuclides at low levels of concentration distributed non-uniformly throughout a large volume. If the maximum radioactivity in a facility is known with reasonable accuracy and is less than 0.002 µCi/g of waste, the facility may be classified as an Other Industrial facility, provided there are no other non-radiological hazards that require a higher classification. Facilities with greater than 0.002 µCi/g might be categorized unrealistically high using inventory-based criteria simply because of the large total waste volume. In such cases, the radioactive waste facility inventory-based categorization may be modified using adjustments to the release fraction or segmentation. Inactive underground waste burial sites and underground contamination sites may be categorized as Radiological facilities when all of the following criteria are met and documented.

a. The soil covering or backfill is maintained to the initial condition by site inspection and maintenance programs.

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b. Natural phenomena will not (1) suddenly remove the soil or backfill covering the site or (2) suddenly transport the contaminants through the intact soil or backfill to a location above ground.

c. The sites are clearly marked and controlled in a manner consistent with the contamination levels.

d. The sites are controlled by site procedures for excavation and penetration work, and are not near areas in which excavation and penetration are allowed. Future excavation and penetration work must evaluated per these criteria.

e. Based on best available information, the underground site does not contain explosives, reactives, or other energy sources, which if uncontrolled, could propel contamination from the ground.

f. The site either contains less than 700 g 235U fissionable equivalent mass or criticality accidents are precluded by segmentation or nature of process.

Material in qualified shipping containers

DOE-STD-1027-92 indicates that material contained in DOT Type B shipping containers (with or without overpack) should not be considered part of a facility�s inventory for categorization as Category 3 or higher (see page A-2 of the standard). It should be noted that DOT containers must be used within their design limits and the certificates of compliance must be current. If the total facility inventory of radioactive material is inside qualified containers, the facility may be classified as an Other Industrial facility, provided there are no non-radiological hazards that require a higher classification.

2.6.2 Facility Classification for Non-Radiological Hazards

2.6.2.1 Process

Each of the non-radiological hazards (e.g., toxic materials, energy sources, reactive materials) that were not screened out during the hazard screening will be analyzed further to determine the facility classification for non-radiological hazards. A consequence-based evaluation will be used to determine the facility classification for toxic materials. The consequence-based evaluation determines the potential health effects to both on-site and off-site populations due to a release of toxic material. The consequence-based classification is determined based on a comparison of the health effects to the criteria identified in the tables below. Classification of other non-radiological hazards (e.g., energy sources) is discussed later.

The results of the facility classification should next be compared with results of previous facility classifications for similar facilities to determine if it is reasonable and consistent with experience. For a consequence-based evaluation, the analyst should consider the impact of the key assumptions used in the analysis. The appropriateness of the classification should also consider whether or not the hazards need further analysis to adequately understand the nature of the hazard or to define the need for special controls for safety and the results should be documented as described in this application guide.

2.6.2.2 Criteria for classification of hazardous materials

DOE Order 5481.1B indicates that consideration should be given to classifying non-radiological hazards as Low, Moderate, and High. DOE has issued guidance such as DOE-EM-STD-5502-94 that provides additional information useful in determining the hazard classification of non-radiological hazards. DOE-EM-STD-5502-94 classifies facilities into four categories: (1) Nuclear, (2) Non-nuclear,

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(3) Radiological, and (4) Other Industrial. The DOE-EM-STD-5502-94 �Other Industrial� classification corresponds to hazards below the Radiological and Low Hazard thresholds.

The general non-radiological hazard screening health effects guidelines shown in Table 2 are based on the information provided in DOE Order 5481.1B and in standard DOE-EM-STD-5502-94. Table 3 presents the criteria for the evaluation of toxic materials. Figure D-2 in Appendix D provides a flowchart for the consequence-based method of facility classification.

Table 2. DOE non-radiological hazard screening guidelines

Hazard Class Guideline High Those with the potential for on-site or off-site impacts to large numbers of persons or for major

impacts to the environment. Moderate Those that present considerable potential on-site impacts to people or to the environment, but at

most, only minor off-site impacts. Low Those that present minor on-site and negligible off-site impacts to people or to the environment.

Other Industrial Defined in DOE-STD-5502 as those that are below the Radiological and Low hazard thresholds.

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Table 3. Non-radiological hazard screening health effects criteria

Hazard Class On-site Off-site HIGH Designated by DOE

MODERATE Irreversible effects to any individual not present in the immediate operating area of the accident.

Irreversible effect to any person.

OR

Reversible effect to a large number of people.

LOW Irreversible effects to a few individuals present in the immediate operating area of the accident.

OR

Reversible effect to a large or very large number of people.

Reversible effect to a few people.

OTHER INDUSTRIAL Consequences less than that defined for Low. Consequences less than that defined for Low.

Irreversible effect is defined as a significant effect on a person�s quality of life, e.g., serious injury. Reversible effect is defined as no significant effect on a person�s quality of life, e.g., minor injury. The terms used to describe the number of people affected are defined as follows: few - less than tens; large - tens; very large - hundreds.

The guidance provided in Table 4 can be used to determine whether a chemical exposure should be considered irreversible, reversible, or negligible.

In addition to the criteria provided in Table 4, Emergency Response Planning Guidelines (ERPGs) developed by the American Industrial Hygiene Association may be used to predict the severity of health effect associated with chemical exposures:

1. Concentrations less than ERPG-1 can be considered as having negligible health effects, 2. Concentrations between ERPG-1 and ERPG-2 can be considered as resulting in reversible health effects, and 3. Concentrations above ERPG-2 can be considered as resulting in irreversible health effects.

It should be noted that ERPGs only currently exist for a limited number of chemicals. Therefore, ERPG alternatives must be used for many chemicals. The DOE-Headquarters (HQ) Office of Emergency Planning and Operations Subcommittee on Consequence Assessment and Protective Actions has developed a hierarchy of alternative criteria, which is included in Attachment 2 of Appendix A.

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Table 4. Chemical health effect exposure levels1

IRREVERSIBLE CONCENTRATION > 1.0 • IDLH

REVERSIBLE 0.1 * IDLH ≤ CONCENTRATION ≤ 1.0 • IDLH

NEGLIGIBLE CONCENTRATION < 0.1 • IDLH 1Exposure levels shown are only to be used for facility classification. Chemical concentrations should be the highest five-min time-weighted-average (TWA). If IDLH values are not available, use the following as equivalent. They are listed in decreasing order of preference. 0.1 * LC50 1.0 * LCLO 0.01 * LD50 0.1 * LDLO 500 * TLV IDLH = Immediately Dangerous to Life or Health, a maximum concentration from which, in the event of respirator failure, a healthy male could escape within 30 min without experiencing any escape impairing or irreversible health effects. LC50 = The concentration (ppm or mg/m3) of a substance in air expected to cause death of one-half of the exposed population. LCLO = The lowest concentration (ppm or mg/m3) of a substance in air expected to cause death to some of the exposed population. LD50 = The dose of a substance (mg substance/kg subject body weight or mg•min/m3) expected to cause death of one-half of the exposed population. LDLO = The lowest dose of a substance (mg substance/kg subject body weight) expected to cause death to some of the exposed population. TLV = threshold limit value, the TWA concentration for a normal 8-hr work day and a 40-hr work week, to which nearly all workers may be repeatedly exposed, day after day, without adverse effects.

2.7 DETERMINATION OF CONSEQUENCES

The objectives of this step are to determine the potential health effects from an accidental release of a hazardous material and to determine the approximate number of people affected both on-site and off-site. Using the criteria presented in Table 2, the facility is assigned a hazard classification. Calculations are to be performed at an appropriate level of detail considering the physical characteristics of the hazard, release mechanism, demographics, and the ability of the operators and on-site personnel to avoid the hazard and evacuate the area. In general, the analysis should be based on conservative assumptions. However, as described below, credit may be taken for some types of administrative controls. The estimate of potential health effects is in terms of negligible, reversible, and irreversible effects on a person�s quality of life.

Each of the hazardous materials (e.g., toxic materials, combustion products) that were identified in the hazard identification and determined to require further analysis must be considered. The chemical and physical properties of the hazardous materials should be taken into account when determining the possible results of accidents. For example, the analysis should not assume that a block of metal is vaporized and transported to a receptor if there is no energy source to vaporize the solid metal. The actual configuration of the specific facilities should be taken into account when calculating consequences of accidents in those facilities.

To take credit for on-site evacuation, the on-site people must be able to detect the release of the hazard, and avoid it. Generally, only operating personnel in the immediate release area are considered candidates for evacuation. Credit is not taken for evacuation of off-site people. Credit is also not taken for active or passive mitigation except for DOT containers used within their design limits. If the operation of a component or system makes the consequences worse, then the calculations should assume that component or system is operating. For example, if a ventilation system�s operation would make the off-site consequences of a release worse, then the off-site calculations should assume the ventilation system is operating. For the same hazard, if operation of the

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ventilation system would make the on-site consequences better, then the on-site calculations should assume the ventilation system is not operating.

Credit may be taken in calculating the consequences of accidents for administrative controls that limit the amount and kinds of materials that can be taken into a facility and the handling of material in the facility. However, no credit is allowed during hazard screening for other administrative controls, active safety systems, passive safety systems, or safety class items that could either prevent an accident or mitigate the consequences of an accident. Procedures that do not allow material to be removed from a shipping container within a facility would be an example of an administrative control for which credit can be taken. Allowing credit for administrative controls appears to produce meaningful results. A vault in which radioactive materials are stored in DOT-approved containers that are procedurally forbidden from being opened within the vault may receive a lower hazard classification than a facility that processes or handles such radioactive materials outside of DOT- approved containers. The safety documentation requirements should be greater for the facility that handles the radioactive material outside of the DOT-approved containers.

The hazard screening consequence determination may be an iterative process. As in many engineering calculations, the analyst will first employ relatively simple, but conservative methods to estimate the bounding consequences of the hazards. Sometimes in this type approach the conservatism in different steps of the calculations are additive; the results of such calculations may be overly conservative. Thus, it is always appropriate for the analyst to determine if the results are reasonable and consistent with the nature of the hazard. If, in the opinion of the analyst, the initial bounding calculations yield results that do not appear reasonable and consistent with the nature of the hazard, the analyst should contact a more experienced analyst for guidance. Additional, more detailed and/or complex calculations may be appropriate.

When a value is calculated for an exposure to a hazardous material, it does not imply that the exposure is expected to occur, or if it did, that it would be acceptable. The calculation only gives an indication of the relative magnitude of consequences associated with the various hazards. It allows facilities to be prioritized according to this relative magnitude of consequences so that a higher proportion of resources may be allocated to the facilities with the higher potential hazards.

2.7.1 Types of calculations

Most of the scenarios will involve the accidental release of some toxic substance, the atmospheric transport of this substance to a receptor, and the consequences of that receptor inhaling or being exposed to this substance. The substance may be either radioactive, chemically toxic, or both. For analysis of these scenarios the key questions are:

• What is the material? • What are the characteristics of the material? • What is the release mechanism? • How much is released? • Where is the release with respect to the receptors? • What is the working volume into which the material is released? • What are the transport characteristics?

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Additional scenarios may involve the release and transport of a substance in which the consequences arise from other than simple release-transport-exposure considerations. An example would be the release of an explosive gas. The consequences arise from the force of the explosion. For analysis of these scenarios the key questions are:

• What is the material? • What is the energy involved? • What is the release or exposure mechanism? • How much is released? • Where is the release with respect to the receptors?

A methodology for performing consequence calculations is provided in Attachment 1 to Appendix A. When addressing other types of scenarios not identified in the referenced documents, or for complex or unusual scenarios of the types mentioned above, an analyst with specialized experience should be contacted for guidance.

Once the number of people and severity of their health effects have been determined, the criteria and additional qualitative and special considerations (described below) are used to determine the hazard classification for the toxic material.

The chemical concentration used in Table 4 is found by taking the highest 5-min time-weighted average (TWA) concentration to which the accident receptors may be exposed. If the concentration to produce a specific health effect can be specified as a function of exposure time, an alternative approach, as described in Attachment 1 to Appendix A, may be used. The use of the IDLH (or one of the other values defined in Table 4) or the ERPG is appropriate for hazard classification when no other measure of health effects is readily available. If actual information is available on the boundary between irreversible and reversible health effects, and the boundary between reversible and negligible health effects, this information should be used instead of the IDLH values. For evaluations other than hazard classification such as safety analysis reports, an industrial hygienist or toxicologist should be consulted and the IDLH (or its equivalent) should be used only if recommended by them.

2.7.2 Modification of consequence-based classification

The following subsections describe two allowable ways for modifying the consequence-based facility classification for non-radiological hazards. Segmentation of the facility can be handled as was allowed for modifying the categorization for radiological hazards. In addition, a reasonableness test based on experience may be used to modify the classification as explained below.

2.7.2.1 Segmentation

The concept of segmentation described for radiological hazards applies to hazardous chemicals and unique hazardous energy sources. Credit can be taken for the separation of inventory amounts of hazardous materials or separation of energy sources when facility features preclude cumulative effects of releases, interactions, or reactions to common severe phenomena. When segmentation is used to modify the classification, justification of the independence of the facility segments should be documented.

2.7.2.2 Applying the reasonableness test

Implementation of the methods and criteria described in this document are expected to provide reasonable facility classifications in most cases. However, there may be exceptions in which the method results in

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unrealistic or inappropriate classification of facilities. The facility classification should be compared with results of more sophisticated and thorough analysis previously completed for similar facilities and hazards to see if it is consistent. If the result of an existing analysis is the basis for modifying the classification, justification must be provided for similarity of the hazard, location, inventory, form, and conditions. Also, consideration must be given to what action might be required if the previous analysis is superseded or revised.

In this exercise, the analyst should also consider whether or not the hazards need further analysis to adequately understand the nature of the hazard or to define the need for special controls for safety. Because hazard classification is used to determine the appropriate safety documentation level, unusual occurrence reporting requirements, the appropriate natural phenomena performance criteria, configuration management requirements, etc., obtaining the appropriate hazard classification is important. If the results obtained using the approach described in this document seem unreasonable or inappropriate, the Nuclear/Safety Technical Lead should be contacted for further guidance.

2.7.2.3 Special Considerations for Non-radiological Hazards

Carcinogens

Chemicals that are considered carcinogens are listed at http://hmweb.ctd.ornl.gov/complete_carcinogen.html. A facility would be classified as Low if the quantities of carcinogens exceed the RQ values. If there is no RQ listed in Table 302.4, 40 CFR 302, then specialists in industrial hygiene should be consulted for assistance in determining the facility classification. Currently, there are no criteria for a higher classification due to the carcinogenic hazard. If a material is carcinogenic solely due to radioactivity, treat material as radioactive hazard, and note assumptions.

Biohazards

Biohazards are biological agents or conditions, such as infectious organisms, that constitute a hazard to man. The U.S. Environmental Protection Agency (EPA) does not consider biohazards when establishing RQs. There are no known criteria for making a determination as to whether this hazard is occupational or unique. Specialists in industrial hygiene and the Installation Facility Safety Manager should be consulted for guidance in facility classification when a biohazard is present.

Asphyxiant hazard

Asphyxiation is generally a concern for the release of a gas that is heavier than air. The gas, if released, could displace breathing air. TQs for asphyxiant gases have not been established because the hazard is characterized by buoyancy of the gas in air, configuration of the volume into which the release occurs, and air movement. The effects of the potential release of asphyxiant gases are generally limited to areas within the facility boundary. If an asphyxiant gas is released in a facility where the gas could be trapped in volumes at a low elevation, and if unsuspecting persons could be present, it may be necessary to classify the facility as Low. No criteria are apparent for classifying a facility as Moderate due to the asphyxiant hazard.

A simple calculation is recommended using the amount of gas released and the available entrapment volume. If results indicate the oxygen level could be reduced from the normal 21% to 18% or less of breathing air due to increased asphyxiant gas concentration, consideration should be given to classifying the facility as Low for this hazard. It is necessary to use judgment in classifying a facility for the asphyxiant hazard. In addition to knowledge and experience with the situation being evaluated, judgment should be based on the consideration that occupational hazards are controlled by standard industrial safety provisions, but unique hazards require facility safety analysis to determine the need for structures, systems, components, activities, or

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conditions for facility safety. Facilities with occupational asphyxiant hazards are considered to be Other Industrial facilities.

Incompatible chemical reaction products and combustion products

A list of incompatible chemicals is provided in Attachment 3 to Appendix A. It is necessary to determine the quantity of reaction products that could be formed if sufficient quantities (i.e., > 1 kg) of incompatible chemicals are present in the same area, and the potential reaction products are toxic. The quantity of reaction products can be estimated based on the chemical reaction equation and the quantities of materials that are present. The limiting inventory of one of the reactants will determine the maximum amount of reaction product(s) produced. The analysis of the reaction products would then proceed similarly to the analysis of other hazardous materials (i.e., postulate release scenario and determine consequences).

Industrial plating shops are an example of operations where incompatible chemicals that could produce a hazardous reaction product are found. Two process liquids that are used separately are nitric acid and a solution of copper cyanide in sodium cyanide. All three chemicals are listed in Table 302.4, 40 CFR 302.4, and therefore, are identified as unique hazards by criteria used in hazard identification. A spill of any of these chemicals raises safety concerns because MSDSs indicate skin contact and inhalation of vapors are important health hazards. Neither chemical is flammable or very volatile and hazards would appear to be limited to persons near spills. However, if the two liquids are not kept separate, they react to produce hydrogen cyanide (HCN). HCN is a highly toxic, highly flammable gas at room temperature. It could be dispersed to adjacent areas and seriously impact persons beyond the facility boundary. Although not normally present in the copper plating process, HCN should be identified as a hazard because it is an incompatible chemical reaction product.

A similar situation exists for combustion products. Combustion, or decomposition upon heating to elevated temperatures without combustion of some chemicals, produces hazardous (toxic) products. The amount of burning (or decomposing) material should be used to determine the stoichiometric amount of product that should be treated like any other hazardous material in facility classification. A Fire Hazards Analysis or a survey by Fire Protection Engineering should, if available, be consulted to identify the expected combustion products.

Energy sources

Energy sources can be a hazard to facility workers, other on-site persons, or the public from electrical shock, moving objects, blast pressure, radiant heat, or beams of energy or particles which originate in devices such as lasers, accelerators, or X-ray machines. The types of energy sources are identified in the FDD.

In facility classification, the analyst should consider the maximum energy that could be released, the distance and direction of persons from the energy source, and the presence of barriers such as passive structures and shielding. A facility should be classified as an Other Industrial facility if it contains only occupational energy hazards that are controlled by standard industrial safety provisions. To classify a facility as Low or Moderate for unique stored energy hazards, thought should be given to the benefit or usefulness of facility safety analysis. Such classifications should only be made if facility safety analysis might determine the need for structures, systems, components, activities, or conditions for protection of persons at locations of interest. If impacts are limited to persons within the facility, consider classifying the facility as Low. If impacts could extend to persons beyond the facility boundary, consider classifying the facility as Moderate.

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2.8 DOCUMENTATION

Documentation should be sufficiently comprehensive and clearly organized to be understandable to a reviewer who is not familiar with the facility. It is important that all facilities have a record showing that hazards have been identified and screened to separate the occupational hazards and the unique hazards. Each new or modified facility should be classified either as an Other Industrial facility or categorized/classified for radiological and non-radiological hazards using criteria established in this document.

Hazard identification and facility classification documentation should include the following information: (a) facility identification, (b) facility classification for both radiological and non-radiological hazards, (c) date the document was prepared, (d) persons involved in preparing and approving the document, and (e) the basis for the facility categorization. An effort should be made within the documentation to minimize references to other SB documents.

The cover page identifies the facility, the results of the hazard identification and facility classification activity, persons involved in preparing the document, and the date the work was performed. A brief description of the facility is desired to describe the primary functions and purpose of the facility and the scope of the hazard identification and facility classification task. An explanation should be provided if materials are excluded from hazard identification using the hazard screening criteria.

If only occupational hazards are identified, the cover page indicates the facility is categorized as an Other Industrial facility and the hazard screening results are recorded on the PHS worksheet. This is sufficient documentation for Other Industrial facilities.

For unique hazards, the basis for facility categorization may involve a simple comparison of inventory and TQs. In this case, the documentation might only include the cover page and a table showing the inventory, the TQs, and the results of the comparison. The basis for facility classification may include a consequence calculation. The consequence-based evaluation should be included in the hazard classification document. If the initial categorization/classification is modified by taking credit for segmentation, or by adjusting TQs for release fractions, the justification and basis should be provided. If special considerations are used, these should be described.

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3. HAZARD ANALYSIS

The HA methodology provides a comprehensive assessment of facility hazards and/or accident scenarios that could produce undesirable consequences for BJC workers and the public. This includes hazard identification, screening for SIHs, and risk binning of events based on frequency and consequence levels. The HA provides the basic hazard and/or release event information used in Documented Safety Analyses (DSAs) and to derive Technical Safety Requirements (TSRs). The HA is a key input to accident analysis and control selection. It is also intended to give sufficient �up-front� information to determine whether simple inventory controls or more complicated and costly systems or system modifications are needed to prevent or mitigate certain hazards in the DSA.

The initial step in performing a Hazard Analysis is to assemble the team that will be conducting the analysis. The �full� HA team consists of the HA team leader, the �core� HA members, and additional functional representatives/experts with limited participation. The number of HA team members will vary depending on the complexity of facility operations and hazards associated with the facility. A typical team has a core group with the following functions represented: safety documentation projects, nuclear safety (usually assigned as HA team leader), facility operations/engineering, and facility regulatory programs. The full HA team includes, on an as-required basis, representatives from the following disciplines accident analysis, frequency analysis, fire protection, criticality safety, radiation control, structural mechanics, emergency management, and control selection and TSR development. The core group performs the majority of the work while the secondary group provides consultation and assistance in specific areas of knowledge and experience.

The HA methodology presented in this procedure is a hybrid of the What-If/Checklist and the Preliminary Hazard Analysis methods as presented in Guidelines for Hazard Evaluation Procedures (CCPS 1992). The example flowchart in Figure 5.3 of this reference provides a method for selecting a specific Hazard Evaluation technique. Using this flowchart, the technique is selected with the following criteria:

• The Hazard Evaluation study is for regulatory purposes

• No specific Hazard Evaluation method is required

• This is not a recurrent review (for new developments, once an acceptable Hazard Evaluation is performed, recurrent reviews to update the Hazard Evaluation may be acceptable)

• Expected results are a list of specific accident situations plus safety improvement alternatives

• The results will not be part of a Quantitative Risk Assessment

At this point in the decision process, the methods common to the applicable parts of the decision tree are the What-If, What-If/Checklist, and Preliminary Hazard Analysis methods. The hybrid combination of the methods is to strengthen the analysis results and provide more consistent development and demonstration of completion for DSAs.

The HA procedure is divided into two main parts: hazard identification and hazard evaluation. Hazard Evaluation covers the Unmitigated Hazard Evaluation and the Mitigated Hazard Evaluation.

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3.1 HAZARD IDENTIFICATION

Hazard Identification is a comprehensive, systematic process by which all known facility hazards (hazardous materials and energy) are identified, recorded, and screened. Screening is performed to eliminate material/energy types and quantities that are considered SIHs that are not initiators and/or contributors to undesired events that may cause radiological or chemical releases.

The hazard identification process should clearly define the project, facility, or activity for which the hazards are examined. The location, functions, boundaries, and interfaces should be described so there is no uncertainty about the identity of the facility for which hazards are reviewed.

The Hazard Identification done for the HA differs greatly from the Hazard Identification completed for the Initial Hazard Categorization/Classification. In the Initial Hazard Categorization, the key objective of hazard identification was the separation of occupational hazards and unique hazards. This was accomplished by first reviewing materials, energy sources, and operating conditions associated with the facility to determine hazards that are present. These hazards were then compared with screening criteria to determine if the hazards are occupational hazards or unique hazards. If there are only occupational hazards in a facility, the facility is classified as an Other Industrial facility, and no further safety analysis is necessary. However, if unique hazards exist within the facility, and additional safety analysis is required, a more vigorous hazard identification process may be performed for use in the HA. The Hazard Identification for the HA includes a much more extensive list of hazards that can possibly be identified and recognizes any hazard that has the potential to become an event initiator. Information gathered during the Initial Hazard Categorization should be used at least as the starting point for the HA hazard identification.

Hazard Identification is divided into three steps: 1) a division of the facility into �facility areas,� 2) facility walkdowns, and 3) screening for SIHs.

3.1.1 Division of the Facility

The HA team should divide the facility into �areas� to facilitate hazard identification and evaluation. These areas may be individual unit operations, individual or grouped facility systems, specific function(s), and/or physical boundaries inside the facility. The term facility �area� is used in the HA process to distinguish from facility �segments� that may have been previously defined during the Initial Hazard Categorization/Classification. However, this distinction does not preclude the use of facility segments as facility areas.

The facility of interest should be divided into structures, systems, subsystems, and phases appropriate for the organized presentation of data about hazards. The organization should be designed to assist a person unfamiliar with the facility or activity in searching, retrieving, or using the data for activities related to facility safety analysis. As an example, an enriched uranium facility which converts UF6 to UF4 could be divided into the following systems: feed autoclave, sampling autoclave, fluorine supply, hydrogen supply, reactor, cold baths/chemical traps, and the potassium hydroxide supply. Avoid dividing a facility to the component level of detail (e.g., tanks, pumps, piping, etc.) because unnecessary complexity may compromise the usefulness of information.

3.1.2 Facility Walkdowns

Facility walkdowns include both physical walkdowns and information walkdowns. Physical walkdowns permit the team to familiarize themselves, first-hand, with actual facility systems, processes, practices, equipment, and inventory. Information walkdowns is the process of HA team-members reviewing existing safety documentation, design/system drawings, or procedures in the context of Hazard Identification. The team

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should perform physical and/or information walkdowns to identify hazardous materials and energy sources for each facility area.

An inventory and screening task, which should be completed as part of the FDD and/or Initial Hazard Categorization/Classification, produces a listing of all known radiological and chemical hazards, including material that may be excluded from the DOE-STD-1027-92 Hazard Categorization (e.g., sealed sources or material in Type B containers). The inventory should include the material, quantity, location, form, and other pertinent information regarding the material (e.g., concentration). Chemical inventories of hazardous chemicals as defined in 29 CFR 1910.119, 40 CFR 302.4, and 40 CFR 355 should be obtained. Additional hazards may be identified, which, due to the potential chemical interactions, should be evaluated, as necessary, as part of Hazard Evaluation.

The information walkdown should include a review of the following:

• Facility Description Document, which includes the facility description and hazardous material inventory.

• Existing safety documentation (SARs, Bases for Interim Operation, TSRs, Project Design Documents, Fire Hazards Analysis, etc.)

• Facility or Operational Safety Plans and/or Integration Work Sheets,

• Consultations with facility system and/or process experts, operations staff, ES&H Team, and workers

• HAs, for neighboring facilities, to determine if an event at that facility could initiate an event for the subject facility

Hazard Identification Tables, used to document the results of Hazard Identification, are a useful �checklist� when performing physical or paper walkdowns. Table B-1 in Appendix B provides an example of a Hazard Identification Table. Use of this table is recommended, but not required. The table has five columns, described as follows:

• Item�A specific number provided for each facility hazard.

• Hazard Energy Source or Material � This is a checklist of potential hazards that may be in the facility. A large general list is provided to allow the table to be used for a variety of facilities.

• Exists�This is used to document whether the hazard exists in the particular facility area. Each item in the list requires either a �Yes� or a �No� response.

• Description�This column is used to characterize the hazard in sufficient detail to allow the HA Team and reviewers to understand the hazard. Location of the hazard (in sufficient detail to locate the hazard within the facility area), quantities, and any clarifying information are useful to include in the description.

• Disposition�This column is for documenting the final disposition of the hazard and is not used during Hazard Identification. When the Hazard Evaluation process is complete, each identified hazard must be properly dispositioned to aid in demonstrating completeness. Use of this column is further discussed later in this chapter.

Using a separate table for each facility area, the HA team members performing facility walkdowns should fill in the third column, �Exists,� for all hazards in the table and the fourth column, �Description,� for the hazardous material and/or energy sources noted during the walkdown. After the walkdown, the team should

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meet to discuss the results and develop a single, �master� hazards checklist for each facility area. During the development of the �master� checklist, care should be taken to identify additional hazards or hazardous materials that are a byproduct of the process (e.g., hydrogen generated by the dissolution of metal by acids during a recovery process).

NOTE: The hazards listed in the Hazard Identification Table in Appendix B are not intended to be an exhaustive list of the potential hazards. Therefore, this table may need to be modified to support the analysis of the respective facility.

3.1.3 Screening of Standard Industrial Hazards

The third step in the Hazard Identification process is the screening of SIHs. These are defined as materials or energy sources that are routinely encountered in general industry and construction, and for which national consensus codes and/or standards (e.g., Occupational Safety and Health Administration [OSHA] and DOT) exist to govern handling and use and are implemented at the facility. In accordance with DOE-STD-3009-94, CN 1 (DOE 2000), common hazards are not typically evaluated and are evaluated only to the extent that they could act as initiators and contributors to events that result in a radiological or chemical release. The HA team screens each identified hazard for each facility area based on material and/or energy types and quantities using the guidance and screening criteria provided in Appendix C.

If the identified hazard meets the appropriate screening criteria, then the hazard is screened as a SIH. No further consideration is given to this hazard except as a potential initiator or contributor to an event that releases radiological or hazardous material. If the identified hazard does not meet the appropriate screening criteria for identification as a SIH, then the hazard is carried forward to the Hazard Evaluation phase.

For completeness, the hazard sources screened as SIHs are documented in this table stating the appropriate screening criteria in the disposition column. Note: The screening documentation in the Hazard Identification table should also include any screened chemical and/or radiological hazardous materials. This table can also provide useful input to the Unreviewed Safety Question Determination process by providing a complete list of hazards, including screened hazards, that can be used for comparison to see if new hazards have been added or if the hazard no longer meets the screening criteria.

3.1.4 Results of Hazard Identification

Hazard Identification Tables index all identified hazards and corresponding locations for each facility area, as well as documents the hazard screening. The recommended format of the Hazard Identification Table is given in Appendix B.

3.2 HAZARD EVALUATION

Hazard Evaluation begins following the comprehensive identification of all known hazardous material and energy sources. As described in this guide, the Hazard Evaluation is performed to meet the requirements of DOE-STD-3009-94, CN1. The hazard evaluation may also be used for all safe harbor methods, including DOE-STD-3011-94 (DOE 1994c), but the author should use a �graded approach� depending upon the hazards. The purpose of the Hazard Evaluation is to ensure a comprehensive assessment of facility hazards and focus attention on those events that pose the greatest risk to the public and the workers.

At a minimum, all core members of the HA Team (such as nuclear safety, and facility operations/engineering representative) should be involved with all aspects of the Hazard Evaluation. Secondary

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team members with other special disciplines (such as frequency analysis, fire protection, emergency management or criticality safety) provide support, as needed.

The scope of the Hazard Evaluation includes:

• All aspects of facility process and operation including design, construction, mission-oriented operations, deactivation, transition surveillance and maintenance, and decontamination and decommissioning, as well as any planned operations described in the FDD.

• Natural phenomena (e.g., earthquakes, tornadoes, straight-winds), external events (e.g., aircraft and vehicular impact), and nuclear criticality (where applicable).

• Consideration of the entire spectrum of possible events for a given hazard in terms of both frequency and consequence levels (e.g., from a small localized fire to a large propagated or facility-wide fire).

• Hazards addressed by other programs and regulations (e.g., Process Safety Management, OSHA, Resource Conservation and Recovery Act, DOT, Environmental Protection Agency) only if loss of control of the hazard will result in a release.

The scope of the Hazard Evaluation does not include:

• Hazards screened as SIHs

• Willful acts, such as sabotage

Detailed information regarding hazardous material and energy sources in the context of facility area and/or whole facility operations is the basis for specific release events. Event categorization, identification of event cause(s), assignment of initiating event frequency and unmitigated consequence level, initial risk binning, identification of potential mitigative and preventive features, and mitigated frequency and consequence level determination are tasks performed during Hazard Evaluation.

This information should be collected and organized in Hazard Evaluation Tables. These tables are a useful guide for performing the evaluation and provide an effective format for documenting the results, and are used to document both Unmitigated and Mitigated Hazard Evaluation results. A sample format is provided in Table 5, and detailed discussion of each piece of information contained within the Hazard Evaluation Table is presented later in this chapter. An example of a typical Hazard Evaluation Table using the sample format is shown in Appendix B. The format and content of the table may be modified to suit the needs of the analysis. The team should produce a separate Hazard Evaluation Table for each facility area, and should also define a single general hazard facility-area that includes hazards that could involve more than one facility-area (e.g., facility fire and earthquake).

The Hazard Evaluation process may be divided into three steps: Identification of Initial Conditions, Unmitigated Hazard Evaluation, and Mitigated Hazard Evaluation.

3.2.1 Initial Conditions

Prior to beginning the evaluation, the Initial Conditions (ICs) for the facility are determined and documented. As early as possible in the process it is desired to document inventory limits or any proposed changes to expedite HA. ICs are specific conditions that are a part of facility operations. ICs may include assumptions, inventory information, specific passive features (i.e., no mechanical or human involvement) such

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as the facility construction and location. Any ICs thus identified must have the specific information for which the IC is valid before it can be credited in the Unmitigated Hazard Evaluation. Examples of ICs are:

• Building/Facility construction is capable of withstanding a surface vehicle impact without adverse affects on facility operations (Note: This does not cover vehicle impacts on support or process equipment located outside the main facility)

• Facility and process inventories are limited to those identified. (Note: The inventory should give specifics such as design information relating to tank volumes and concentrations, location within the facility, etc.)

• Building construction is Performance Category-3 (PC-3). Frequencies for Tornado/High Wind and Seismic events impacting the building structure are as identified DOE-STD-1020-94 (DOE 1996).

• Worker�s ability to react to obvious hazardous conditions and to evacuate. This, of course, invokes the assumptions that the workers are physically able to evacuate, and that an evacuation route is available during or immediately following the hazardous condition.

These ICs are part of the input to the control selection process and may require protection as TSRs. Therefore, care must be taken regarding the selection of ICs and in determining the impact the ICs will have on the Hazard Evaluation. ICs, other than those that are part of the facility design basis (e.g., PC-3 construction) or that will obviously prevent an event (e.g., structure able to withstand vehicle impact), are discouraged from being used since they may skew the unmitigated risk levels and result in unanalyzed or inadequately controlled hazards. For example, a fire door may be credited as an IC for preventing fire propagation. This control may fail (e.g., door is blocked open) so it does not completely prevent the event, but only reduces the frequency. If the frequency reduction �moves� the event risk to a level that does not require further analysis, then the adequacy of the control is not evaluated and the safety functions of the door may not be properly determined. Additionally, this may lead to a larger control set since controls identified for other fire events (e.g., combustible material control, fire suppression) may be adequate to protect against this event.

ICs should be uniquely numbered for reference in the Hazard Evaluation Tables using �IC� as the leading designation. This is to support identification of specific conditions or features that require TSR protection and to provide the basis for the requirement.

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Table 5. Sample Hazard Evaluation Table for (Facility Area)

Unmitigated Mitigated

Event No.

Event Cat.

Event Description Causes

Freq. Level

Consequence Level

Risk Rank

Method of

Detection Preventive Features Mitigative Features

Freq. Level

Consequence Level

Risk Rank

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3.2.2 Unmitigated Hazard Evaluation

The Unmitigated Hazard Evaluation is performed to determine the risks (frequencies and consequences) involved with the facility and its associated operations without regard for any safety controls or programs. Unmitigated refers to the determination of the frequency and consequences without credit given for preventive or mitigative features other than the specified ICs. This is essential to avoid taking credit for any type of active or passive barriers or controls, which must then be designated as a Safety Class Structures, Systems, and Components (SSC) or Safety Significant SSC depending upon which receptor (Offsite Public, Co-located Workers, or Facility Workers) risk was reduced. During the Unmitigated Hazard Evaluation, the Material at Risk will equal the available hazardous inventory that can be acted upon during the postulated event. No credit will be taken for any controls. However, the laws of physics will be obeyed. Information that can be captured in the Hazard Evaluation Table during the Unmitigated Hazard Evaluation includes the following:

• Event Number

• Event Category

• Postulated Event Description

• Causes

• Unmitigated Frequency Level

• Unmitigated Consequence Level

• Unmitigated Risk Bin

• Method of Detection

Additional detail and pertinent methodology information for each of the Hazard Evaluation Table categories is provided in the following sections.

3.2.2.1 Event number

Events are numbered to provide each with a sequential reference. The numbering system may be chosen such that facility area is identified mnemonically. For example, consider a facility area identified as Pump House. The mnemonic PH may be chosen to represent this facility area, and events would be numbered PH-01, PH-02, etc.

3.2.2.2 Event category

Events are categorized according to the nature of the event, with the exception of events initiated by external or Natural Phenomena Hazards. A standard list of event categories expected at DOE sites is listed below, along with a general description of the general consequence source. The first five categories are for internally initiated events, which are typically process-related events. The final two categories are externally initiated events.

E-1 Fire � Consequences typically due to inhalation/ingestion of released hazardous material.

E-2 Explosion � Consequences typically due to inhalation/ingestion of released hazardous material.

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E-3 Loss of Containment/Confinement � Consequences typically due to inhalation/ingestion of released hazardous material.

E-4 Direct Radiological/Chemical Exposure � Consequences typically due to direct exposure (contact chemical exposure, radionuclide �shine�).

E-5 Nuclear Criticality � Consequences typically due to direct exposure and release of fission products

E-6 External Hazards � Consequences typically due to inhalation/ingestion of released hazardous material. Depending on specific event, direct exposure consequences may also be applicable.

E-7 Natural Phenomena � Consequences typically due to inhalation/ingestion of released hazardous material. Depending on specific event, direct exposure consequences may also be applicable.

3.2.2.3 Postulated event description

A brief description of a postulated event, which clearly defines the nature of the event, is given in this column. The event description should include event progression information, location, the release mechanism (e.g., fire, pressurized release, spill, etc.) or other consequence mechanism (e.g., direct exposure), and the affected hazardous material, including the MAR that may be impacted by the event.

Using the Hazard Identification Tables as a basis, the HA team develops event scenarios for each facility area where a potential exists for a release of hazardous energy and/or material, and establishes a link between the hazard groups identified with the potential events caused by the hazards. Table B-2 of Appendix B provides an aid for identifying potential events but is not intended to be comprehensive or to limit the scenario development. The full character of the hazard must be considered when developing potential scenarios. For example, electrical hazards are identified in the table as potential contributors for fires, explosions, and worker injuries. However, if an electrical insult to a chemical may produce an unwanted reaction (e.g., cause the chemical to break down into toxic components), then that event must be identified as well.

Scenarios should cover the entire spectrum of possible events for a given hazard, from small consequence events, for which procedures or equipment is acknowledged to provide adequate protection, to �reasonable worst-case� conditions. Unlike �worst-case,� �reasonable worst-case� does not necessarily consider every parameter in its most unfavorable state. For example, if a toxic material is normally handled as a liquid at room temperature during processing, a reasonable worst-case release does not necessarily have to consider a spill with the liquid at 130°F. Follow-on events, such as a fire following a seismic event, should be identified and evaluated to ensure that the entire spectrum of possible events is addressed.

3.2.2.4 Causes

The causes of the postulated event are listed. A cause specifically states the failure, error, operational, and/or environmental condition that initiated the release event. Causes are synonymous with initiating events, and therefore, need to be clearly identified to support frequency evaluation. The Hazard Identification Tables are used as a guide in developing specific causes for release events also provides guidance on potential causes for various events. When a hazard is identified as a potential cause for an event, the specific event number is identified in the Hazard Identification Table �Disposition� column. Multiple event numbers may exist for each hazard identified.

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3.2.2.5 Unmitigated frequency level

Event frequency evaluation is a qualitative or semi-quantitative process that involves assigning a frequency level to each event in the Hazard Evaluation Tables. Frequency levels and descriptions are summarized in the Frequency Evaluation Levels shown in Appendix B, Table B-3, which are based on DOE-STD-3009-94, CN1. The HA team determines which frequency level is appropriate for a particular event based on the event�s cause(s). Frequencies can be qualitatively estimated based on the judgment of the analysts who may utilize the following:

• Existing safety documentation

• Engineering calculations

• Equipment failure rate data

• Data regarding human error

• Facility expert opinion

• Historical accident data

• HA team evaluation

The frequency level is recorded in the Hazard Evaluation Tables according to the Table B-3 lettering scheme, along with a footnote number indicating the source of the frequency used. These references should be summarized at the end of the Hazard Evaluation Tables.

Erring in the conservative direction from best-estimate values accommodates uncertainties in frequency levels. This practice is particularly important when an event frequency is just below the next highest frequency level. For example, 9.7 x 10-3 /year is at the high end of the �Unlikely� level. The HA team, considering the sources, methods, and uncertainty associated with this value, might collectively decide to call this event frequency �Anticipated� rather than �Unlikely�.

When evaluating event frequency, credit may be taken for items identified as ICs. Any IC credited during the frequency determination must be identified below the frequency using the unique IC number.

3.2.2.6 Unmitigated consequence level

Event consequences are documented by specifying the impact on the receptors (described below). For HA purposes, unmitigated consequences are defined as the dose or exposure at specified receptor locations that have been determined without taking credit for barriers or controls that could reduce the consequences, as per DOE-STD-3009-94, CN1. Consequences are a function of the type and characteristics of the hazard, the quantity released, the release mechanism, relative location of the release, and any relevant transport characteristics. Consequences can be qualitatively estimated based on the judgment of the analysts who may utilize the following:

• Simple source term estimates

• Existing safety documentation

• Qualitative assessment by the HA Team

The HA team utilizes its discretion, expertise, and knowledge of facility hazards to select one or more of the above methods appropriate for consequence determination. When evaluating consequence levels, direct

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radiation exposure or chemical contact consequences to the worker are addressed in Event Category E-4 Events, while E-6 and E-7 Events are events where the exposure to the hazardous material could be significant (e.g., earthquake damages shielding, allowing direct radiation exposure).

Unlike frequency levels that cover two orders of magnitude, consequence levels sometimes span less than one order of magnitude. Thus, a more refined effort may be required by the HA team to determine the appropriate consequence level for a given event and receptor. Much like frequency evaluation, the HA team is encouraged to err in the conservative direction, especially for those events with consequences at the high end of a given level.

Consequence evaluation is the process of determining which of the consequence levels (shown in Appendix B, Tables B-4 and Table B-5) are relevant to the three receptors for a particular release event. These tables give the radiological and chemical consequence levels that can be used for risk binning process. Receptors are as follows:

• Facility Workers: Individuals immediately adjacent to, or in, the occupied area of the hazard

• Co-located Workers: Individuals outside the occupied area of the hazard but within the site boundary

• Offsite Public: All individuals outside the DOE site boundary

NOTE: The HA is concerned with the maximally exposed individual at each of the receptor locations.

When evaluating event consequences, credit may be taken for items identified as IC. Any IC credited during the consequence determination must be identified below the consequences in the Hazard Evaluation Table using the unique IC number.

The Hazard Evaluation Tables should provide the impact of the event on the three receptors for each of the postulated release events under the �Consequence Level� heading of the Hazard Evaluation Tables. Terminology for receptors and consequences is taken from Appendix B Tables B-4 and Table B-5. If the event may result in radiological and chemical consequences, the cause of the consequences should be identified (e.g., a heading for radiological, with the radiological consequences listed below, then a heading for chemical, with the chemical consequences listed below.) This is especially important in the case of the offsite public since there are no DOE Safety Class control requirements for chemical hazards (CCPS 1992). Additionally, information on consequences, other than chemical or radiological exposure to individuals, should be presented in this column. This information should include the physical consequences to the worker (e.g., an explosion could result in a worker fatality) or safety impacts in other areas of the facility (e.g., a lightning strike knocks out facility power, which in turn disables the nitrogen/purge system).

3.2.2.7 Unmitigated risk bin

The objective of risk binning is to focus attention on those events that pose the greatest risk to the Offsite Public, the Co-located Worker, and the Facility Worker. Higher risk events might be candidates for additional analysis and/or control selection evaluation. Using event frequency and consequence levels, the HA team �bins� events in frequency-consequence space to assess relative risk.

Tables B-6, Table B-7, and Table B-8 present the risk binning matrices for the three receptor locations considered in the HA (i.e., Facility Worker, and Co-located Worker, and Offsite Public). In each of these tables, bins are defined by a rectangular matrix in frequency-consequence space. Each bin is lettered for identification purposes.

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Table B-6 and Table B-7 are the risk-binning matrices for the workers, both the Facility Worker inside the facility and the Co-located Worker. Region A represents risk that exceeds the worker risk-binning criteria and requires further evaluation per methodology in the Control Selection Document (CSD). The desired result is that the mitigated combination of consequence and frequency is moved well into the C region, possibly the D region. Region C represents risk that challenges the worker risk-binning criteria. Unmitigated events with risk falling in or challenging Region C may needadditional consideration in Control selection to move the mitigated risk well toward, and possibly into, the D region. Unmitigated events with risk falling in Region D generally have negligible risk and no further action is required..

Table B-8 is the risk-binning matrix for Offsite Public. Region A represents risk that exceeds or challenges the Offsite radiological Evaluation Guideline and/or chemical risk-binning criteria. Events falling into these bins typically require further evaluation per methodology in the CSD. In DOE-STD-3009-94, CN1 terminology, these events are considered �unique,� or �situations of major concern,� with sufficiently high risk that individual examination is needed by accident analysis. The desired result in applying these controls is that the mitigated combination of consequence and frequency is moved well into the C region, and possibly the D region.

Region A1 represents consequences that exceed the radiological Evaluation Guideline per DOE-STD-3009-94, CN1. �There is no predetermined frequency cutoff value, such as 10-6 per year, for excluding low frequency operational accidents (i.e. internally initiated),�. . .�the determination of need is solely driven by the bounding consequence potential.� Operational accident events, which fall into (or challenge) this bin due to radiological consequences, require further evaluation as specified in the CSD. For further information, natural phenomenon events are defined in terms of the frequency of the initiating events and external events are defined with a cutoff frequency of 10-6 (conservatively calculated); these events will most likely be captured within another risk bin.

Unmitigated events with risk falling in or challenging Region B in Table B-8 due to radiological release require further evaluation as specified in the CSD. Unmitigated events with risk falling in Region B due to chemical release may additional consideration within control selection. Again, the desired result is that the mitigated risk is moved well into the C region and possibly the D region. Also in Table B-8, unmitigated events with risk falling in or challenging Region C may need additional consideration in control selection to move the mitigated risk well toward, and possibly into, the D region. Unmitigated events with risk falling in Region D generally have negligible risk and no further action is required.

3.2.2.8 Method of detection

Method of detection includes features designed to detect initiating events or subsequent event progression. These include alarms, monitors, indicators, and an operator�s ability to recognize the events by visual observation or sound. Inclusion of this column in the Hazard Evaluation Table is optional, since the SSCs identified are also captured in the Preventive and Mitigative Features columns.

3.2.3 Mitigated Hazard Evaluation

Mitigated Hazard Evaluation is performed to demonstrate that adequate prevention and mitigation features are selected to reduce the unmitigated event risk below the risk-binning criteria for the Co-located Worker and the Worker. This evaluation is applied only to those events that exceed the risk-binning criteria for Workers and Co-located Workers and have not been evaluated in the accident analysis.

For events where the unmitigated risk exceed the risk-binning criteria for the Co-located Worker and the Facility Worker (i.e., events falling into Region A in Table B-6 and B-7), additional qualitative analyses for the

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Co-located Worker and the Facility Worker may be conducted and documented in the Mitigated Hazard Evaluation. Events that exceed or challenge the Offsite Evaluation Guideline (i.e., events falling into Regions A and A1 in Table B-8) may also be included in this additional analysis.

If an event exceeds the risk-binning criteria for the Co-located Worker and the Facility Worker, controls that have been identified as potentially SC or SS during the accident analysis and control selection can be credited first and then, the event is reevaluated. If the event still exceeds the risk-binning criteria, appropriate members of the HA Team identify additional controls to be credited in an iterative manner until the risk no longer challenges the risk-binning criteria for the Co-located Worker and the Facility Worker. The controls credited during this evaluation must be documented along with the credit given (i.e., the reduction in the event frequency or consequences due to the particular control) in either an appendix to the HA or in a separate Safety Basis Calculation. After the accident analysis, the mitigated hazard evaluation may be modified to reflect the risk rank.

The results of the Mitigated Hazard Evaluation are also documented in the Hazard Evaluation Tables to demonstrate that adequate control(s) has (have) been identified for the events that exceed the risk-binning criteria for the Co-located Worker or the Facility Worker during the Unmitigated Hazard Evaluation. Changes in event frequency, consequences, and risk bin are documented in the appropriate columns in the Hazard Evaluation Table as discussed below.

3.2.3.1 Preventive features

Identification of preventive features should start during the Hazard Identification phase and carry through the end of the analysis. Preventive features are features expected to reduce the frequency of a hazardous event. The identification of such features is made without regard to any possible pedigree of the feature, such as procurement level or current classification. These might include engineered features (e.g., SSCs, etc.), administrative controls (e.g., procedures, policies, programs, etc.), natural phenomena (e.g., ambient conditions, buoyancy, gravity, etc.), or inherent features (e.g., physical or chemical properties, location, elevation, etc.) operating individually or in combination. Preventive features are listed in the Hazard Evaluation Tables such that a distinction is made between administrative and design features. Planned improvements (e.g., modification of the process, addition of equipment) may also be documented in this column, as long as they are designated as such.

Preventive features constitute a significant portion of Defense in Depth (DID) and Worker Safety (required for Chapter 3 of the DSA) and they provide essential input to the control selection task. Therefore, it is important that the identification effort capture essentially all of the possible features that could be counted on to prevent a hazardous event.

Preventive features that were credited for reducing the frequency during the Mitigated Hazard Evaluation are underlined.

3.2.3.2 Mitigative features

Identification of mitigative features should start during the Hazard Identification phase and carry through the end of the analysis. Mitigative features are any features expected to reduce the consequences of a hazardous event. The identification of such features is made without regard to any possible pedigree of the feature, such as procurement level or current classification. Mitigative features must be capable of withstanding the environment of the event. These might include engineered features (e.g., SSCs, etc.), administrative controls (e.g., procedures, policies, programs, etc.), natural phenomena (e.g., ambient conditions, buoyancy, gravity, etc.), or inherent features (e.g., physical or chemical properties, location, elevation, etc.) operating individually

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or in combination. Mitigative features are listed in the Hazard Evaluation Tables such that a distinction is made between administrative and design features.

Mitigative features constitute a significant portion of DID and Worker Safety (required for Chapter 3 of the DSA) and they provide essential input to the control selection task. Therefore, it is important that the identification effort capture essentially all of the possible features that could be counted on to reduce the consequences of a hazardous event. Planned improvements (e.g., modification of the process or addition of equipment) may also be documented in this column as long as they are designated as such.

Mitigative features that were credited for reducing the consequences during the Mitigated Hazard Evaluation are underlined.

3.2.3.3 Mitigated frequency level

The event�s initiating frequency level (from the unmitigated column of the Hazard Evaluation Tables) is modified with the reductions due to credited preventive features. The amount of frequency reduction is dependent on the control(s) and may be defined during the accident analysis. If the frequency reduction is not identified, then the HA Team may make a qualitative evaluation of the reduction based on the failure rate of the control and engineering judgement. An acronym representing the results of frequency evaluation is assigned according to the Table B-3 lettering scheme. As with the initiating frequency level, a reference is added to indicate the source of the frequency and the frequency. Depending upon the complexity of the systems/accident scenarios addressed in the HAs, simplified logic trees, such as event trees or fault trees, may be constructed in order to estimate the mitigated frequency.

3.2.3.4 Mitigated consequence level

The unmitigated consequence levels for each event are modified with the reductions identified during the Mitigated Hazard Evaluation. The credited feature is evaluated to determine what factors affect the consequences when the feature is applied.

3.2.3.5 Mitigated risk bin

Based on the Mitigated Frequency and Consequence Levels, the events are binned in the same manner as during the Unmitigated Evaluation. The final risk bin determined in this manner is used to demonstrate that the prevention and mitigation features reduce the event risk below the established guidelines.

3.2.4 Hazard Evaluation Output

The Hazard Evaluation Tables are the primary output of the Hazard Evaluation effort. An example of a typical Hazard Evaluation Table in a suggested format is shown as Table B-9 in Appendix B. The format and content of this table may be modified to support the needs of the analysis. These tables constitute a portion of the overall results of the HA.

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4. FINAL HAZARD CATEGORIZATION

4.1 INTRODUCTION

Following the unmitigated HA, the final facility hazard category is established. The unmitigated HA considers material quantity, form, location, dispersability, and interaction with available energy sources, but does not consider safety features (e.g. ventilation system, fire suppression system, etc.) which prevent or mitigate the event. The unmitigated HA identifies all hazardous events to be evaluated, and screens those events that are controlled by industry codes and standards or site programs (i.e., common industrial hazards). As such, the unmitigated HA establishes the full set of hazardous events to be analyzed in the AB process.

The results of the unmitigated HA will also be used to identify the final facility hazard category. From the unmitigated HA it may be shown that it is more reasonable for the facility to be categorized lower than its initial categorization. If this is the case, a final hazard categorization is documented to reduce unnecessary safety analysis.

It is important to note that the final hazard categorization is for radiological hazards only; there is no final hazard classification for non-radiological hazards. Therefore, if a facility was initially classified as a Low facility or a higher classification, it will require the full detailed facility safety analysis regardless of the outcome of the unmitigated HA.

4.2 PROCESS

In order to determine the final hazard categorization of a facility, the bounding event considered in the unmitigated HA is further evaluated. In choosing the bounding event, the analyst should consider the event that has the most impact to all receptors. This event will typically be a hazard effecting the entire facility such as the full facility fire.

Once the bounding event is identified, the consequences are compared to the dose thresholds taken from DOE-STD-1027-92. If the consequence dose of the bounding event is at or above 1 rem at 100 meters, then the facility is a Hazard Category 2 facility. If the consequence dose of the bounding event is at or above 10 rem at 30 m, then the facility is a Hazard Category 3 facility. If the consequence dose of the bounding event is below 10 rem at 30 m, then the facility is categorized as a Radiological facility.

This final hazard categorization determines the further safety analysis that is required for the facility. If the facility�s final hazard categorization is Category 3 or higher, it will require accident analysis, control selection, and a mitigated HA (see Figure 1 in Appendix D). If the facility�s final hazard categorization is reduced to a Radiological or lower, then less detailed forms of safety analysis documents will be required (such as a ASA or HASP).

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4.3 DOCUMENTATION

The recommended standard documentation of the Final Hazard Categorization is the Hazards Assessment Document (HAD). A HAD provides the bases and records the hazard categorization of Nuclear Category 3 and Radiological facilities. In addition, the HAD defines certain administrative controls to preserve elements of the categorization process. The hazard categorization for a Category 2 facility may be included within the SB document instead of a separate classification document. A HAD can also be used to document the Initial Hazard Categorization/Classification for Category 3 and Radiological facilities.

The format of a HAD should include the following:

• Standard cover page with hazard categorization and classification

• Brief facility description including a description of current operations

• Inventory of radiological and hazardous materials

• Discussion of inventory techniques and confidence in the accuracy

• Preliminary Hazard Screening

• Initial hazard categorization based on inventory

• Basis of the unmitigated hazards analysis

• Discussion of administrative controls to be used to ensure any initial conditions or assumptions used in the unmitigated hazards analysis are maintained under current operating conditions.

• Final hazard categorization

• Discussion of inventory control methods to ensure the classification remains valid considering current operating or facility conditions

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5. REFERENCES

CCPS (Center for Chemical Process Safety) 1992. Guidelines for Hazard Evaluation Procedures, Second Edition; ISBN 0-8169-0491-X.

DOE (U.S. Department of Energy) 1986. Safety Analysis and Review System, DOE O 5481.1B, November.

DOE 1992. Nuclear Safety Analysis Reports, Order 5480.23, April 30.

DOE 1994a. Hazard Baseline Documentation, DOE-EM-STD-5502-94, August.

DOE 1994b. Recommended Values and Technical Bases for Airborne Release Fractions, Airborne Release Rates, and Respirable Fractions for Materials from Accidents in DOE Fuel Cycle, Ex-Reactor Facilities, by Jofu Mishima, DOE-HDBK-3010-94.

DOE 1994c. Guidance for Preparation of DOE 5480.22 (TSR) and DOE 5480.23 (SAR) Implementation Plans, DOE-STD-3011-94, November.

DOE 1996. Natural Phenomena Hazards Design and Evaluation Criteria for Department of Energy Facilities, DOE-STD-1020-94, Change Notice #1, January.

DOE 1997. Hazard Categorization and Accident Analysis Techniques for Compliance with DOE Order 5480.23, Nuclear Safety Analysis Reports, DOE-STD-1027-92, Change Notice 1, September.

DOE 1998. Integration of Environment, Safety, and Health into Facility Disposition Activities, DOE-STD-1120-98, May.

DOE 2000. Preparation Guide for U.S. Department of Energy Non-Reactor Nuclear Facility Safety Analysis, DOE-STD-3009-94, Change Notice 1, January.

EPA (U.S. Environmental Protection Agency), FEMA (Federal Emergency Management Agency), and DOT (U.S. Department of Transportation) 19987. Technical Guidance for Hazards Analysis, Emergency Planning for Extremely Hazardous Substances, December.

NFPA 1991. Hazardous Chemical Data, National Fire Protection Association, Standard 49.

NIOSH 1994. NIOSH Pocket Guide to Chemical Hazards, National Institute of Occupational Safety and Health, June.

Perry, R.H. and C.H. Chilton 1973. Chemical Engineers’ Handbook, 7th Ed., or later.

SAX, N.I., and R.J. Lewis 1992. Dangerous Properties of Industrial Materials, 8th ed., or later.

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APPENDIX A

ANALYSIS REFERENCES FOR HAZARD CATEGORIZATION/CLASSIFICATION

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INTRODUCTION

This Appendix contains analysis reference documents that support the Hazard Categorization/Classification methodology presented in this Application Guide. This guide presents a method for identifying hazards and categorizing/classifying facilities for safety analysis in accordance with U.S. Department of Energy (DOE) Orders 5480.23 and 5481.1B1. Hazard identification is the process that selects hazards for consideration in facility categorization/classification. Facility categorization/classification reflects the relative magnitude of hazards in a facility, and it is used in implementing a graded approach to facility safety analysis.

The references identified in this guide will be used primarily for hazard identification and facility categorization. The references are grouped by subject matter for Radiological and Non-radiological subject matter. Some references are not reproduced in this appendix due to their length, but a listing of each reference, including a brief description of the reference, is provided below.

RADIOLOGICAL

Reportable Quantities for Classification as Radiological Facility – Appendix B, 40 Code of Regulations (CFR) 302 (not attached)

Provides reportable quantities of radionuclides; if quantities of radionuclides exceed the reportable quantities (RQs), but are less than the Category 3 threshold quantities (TQs) in DOE-STD-1027-92, the facility is categorized as a Radiological facility by inventory. If quantities of radionuclides are less than the RQs, the facility is categorized as an Industrial facility (assuming that there are no significant non-radiological hazards in the facility).

Threshold Quantities for Classification for Category 2 or Category 3 – Table A.1 from Attachment 1, DOE-STD-1027-92 (not attached)

Provides TQs for determining if a facility is either Category 2 or Category 3 based on the inventory of radionuclides in a facility.

Surface Radioactivity – Guides from Attachment 2 of DOE Order 5480.11, 12-21-88 (not attached)

Provides hazard screening criteria for fixed and/or removable radioactive surface contamination.

NON-RADIOLOGICAL

List of Hazardous Substances and Reportable Quantities – Table 302.4, 40 CFR 302 (not attached)

Provides hazard screening criteria for toxic chemicals, combustion products, and carcinogens. If the quantity of hazardous material exceeds the RQ, a consequence-based evaluation will be required to

1 Although these references have been cancelled, replacement guides have not been generated. These documents specify standard current practices across the DOE complex, and; therefore, will be referenced in this guidance document.

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A-4

determine the facility classification for non-radiological materials. If the quantity of hazardous material is less than RQ, the facility is classified as an Other Industrial facility (assuming that there are no radiological hazards that would result in a higher categorization).

Consequence Calculation Methodology (Attachment 1)

Provides methodology for performing a consequence-based evaluation to support classification of non-radiological hazards.

Use of Emergency Response Planning Guidelines (Attachment 2)

Provides a hierarchy of alternative criteria developed by the DOE-Headquarters (HQ) Office of Emergency Planning and Operations Subcommittee on Consequence Assessment and Protective Actions for estimating alternate Emergency Response Planning Guideline (ERPG) values for chemicals in which no ERPGS have been developed.

Reactive Materials and Incompatible Chemicals (Attachment 3)

Provides information from Environmental Protection Procedure EPM-12.0, which can be used in completing the hazard identification and screening regarding reactive materials and incompatible chemicals.

Method for Determining Substitute Reportable Quantities (Attachment 4)

Provides a method for determining substitute RQs for those chemicals that are not listed in 40 CFR 302.

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ATTACHMENT 1

CONSEQUENCE CALCULATION METHODOLOGY

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PREFACE

In the earlier versions of CSET-2, the dispersion coefficients for atmospheric dispersion were based on values recommended by Briggs for the following assumptions: continuous release, level ground, and open-country conditions. These values are smaller (more conservative) than Briggs' values for urban conditions. Recommended values for the horizontal dispersion coefficients for instantaneous releases were half the values for a continuous release. However, the instantaneous values are much more uncertain than the continuous values, and the accuracy of any dispersion model is generally poorer than a factor of two so that any correction for release time is probably not warranted. Also, the close-in model, presented in this revision, blends smoothly into the long-distance model if the continuous values are used. Therefore, Revision 2 recommends that the horizontal dispersion coefficients for an instantaneous release be equal to the values of the horizontal dispersion coefficients for a continuous release.

In addition, the previous versions of CSET-2 recommended that the worst-case (i.e., results in highest downwind concentration) stability class (e.g., F stability for ground-level releases) should be used to establish the facility classification. Based on recent guidance from DOE (e.g., DOE-STD-1027-92),the use of more typical meteorology (e.g., D stability with wind speed of 4.5 m/s) is recommended in this guidance.

Documents reproduced in part in this Appendix:

1. Sanford G. Bloom, Atmospheric Transport Analysis to be Used in Hazard Classification, October 1995. (pages E-1 through E-13)

2. R. A. Just, Guidance for Analyzing the Effects of Postulated Toxic Releases, Internal Correspondence to all SSE Personnel, October 4, 1990. (pages E-14 through E-19)

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ATMOSPHERIC TRANSPORT ANALYSIS TO BE USED IN HAZARD

CLASSIFICATION

SCOPE

This methodology provides some of the techniques that may be used in a �first pass� analysis of the consequences resulting from accidental releases of hazardous substances. It is assumed that the analyst has already been introduced to methods for identifying potential hazards and for postulating accident scenarios. First pass analyses are used to indicate a preliminary hazard classification by employing relatively simple, but conservative, methods to estimate the consequences of the hazards. Second, or higher-order, passes may be required if (a) the results are not low or negligible, (b) the results are inconsistent or �just don't seem right,� or (c) management wants a more realistic assessment.

Most of the scenarios that will be considered in hazard classification involve the accidental release of some toxic substance, the atmospheric transport of this substance to a receptor, and the consequences of that receptor inhaling this substance. The substance may be either radioactive, chemically toxic, or both.

Additional scenarios may involve the release and transport of a substance in which the consequences arise from other than simple release-transport-exposure considerations. An example would be the release of an explosive gas. The consequences arise from the force of the explosion but such estimates are beyond the scope of this course.

Finally, there are scenarios whose principal consequences do not involve exposure to a toxic substance and these are also not considered in this course. Examples are criticality events, exposure to direct radiation (e.g., nuclear radiation, microwaves), and accidents due to personnel contact with electrical, thermal, or mechanical equipment. Such accidents either require very specialized training or are considered standard industrial hazards, which are not analyzed in facility safety documentation.

All analyses of releases of toxic substances involve three basic elements: (1) determining the amount of material released and available for transport (this is called the �source term�); (2) determining how much (usually expressed as a concentration) of the released material reaches humans (this is called �transport calculations� and, since the material usually moves through the air assisted by the wind, it is usually called �atmospheric transport�); and (3) estimating the physiological effects humans would experience from breathing or being immersed in the �cloud� of toxic substance (this is called �dose-consequence analysis�). This methodology concentrates on the first two elements and provides guidance regarding sources of data for making dose-consequence determinations. The purpose of the analysis is to (a) predict the health effects on humans of the released toxic material or (b) show that the concentration levels or exposures are below allowable levels established by DOE or other national agencies such as the National Institute of Occupational Safety and Health (NIOSH).

ACCIDENTAL RELEASE SOURCE TERM Two types of accidental releases are considered in this course: (1) an instantaneous release of some

fraction of the amount of material at risk and (2) a constant, steady release rate over a period of time. The objective is to estimate the amount of material that becomes airborne and is thus available to be inhaled. For first pass analyses, the fractions listed in Table 1 may be used for estimating the amount airborne for various conditions. These fractions are based on engineering judgement and experience using procedures given by Ayer, et al. (1988). These latter procedures should be used for a more detailed analysis.

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For instantaneous releases, the amount airborne is simply the product of the appropriate fraction from Table 1, and the amount of material at risk. The amount of material at risk is estimated from the circumstances of the scenario. If there is no valid basis to assume a smaller amount, the entire inventory of the material in the facility should be considered as the amount of material at risk. The expression for the amount airborne is

Table 1. Fractions for First Pass Estimates of Amount Airborne

Type of release Fraction

Gas 1.0

Simple powder spill 0.001

Simple liquid spill 0.0001

Pressurized powder release 0.01

Pressurized liquid release 0.05

Burning of contaminated combustible solid 0.0005

Burning of contaminated combustible liquid

non-volatile contaminant 0.01 volatile contaminant 1.0

fMQ = (1)

Q is the amount of material airborne, g

f is the appropriate fraction from Table 1

M is the amount of material at risk, g.

Similarly for continuous releases, the amount airborne is simply the product of the appropriate fraction from Table 1, and the rate at which the material is released. The rate at which the material is released and the duration of the release have to be specified. The expression for the rate airborne is

dt

dMfdtdQ = , for 0 < t < τ = 0, for t > τ (2)

dQ/dt is the rate at which the material becomes airborne, g/s

t is the time since the release began, s.

dM/dt is the rate at which the material is released, g/s

r is the duration of the release, s.

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There are methods for estimating release rates when they are not specified, but they are beyond the

scope of this course and are only mentioned here. If you encounter a situation in which a release rate must be estimated, consult either S. G. Bloom (4-6638) or R. A. Just (4-6497) for guidance. Liquid release rates may be estimated using expressions for gravity-flow or forced convection. Gases emerging from pressurized containers can usually be estimated using expressions for choked flow. Gases from evaporating liquids can be estimated using expressions for heat transfer and/or mass transfer.

Uranium Fires

Uranium is a pyrophoric metal and the possibility of uranium fires must be considered in many accident scenarios at the Y-12 and gaseous diffusion plants. The most likely fires involve small pieces (chips) that are the byproduct of machining operations. These can ignite spontaneously and will burn quickly. Large pieces and parts (chunks) can also burn but are more difficult to ignite and will burn slower. The following factors and rates should be used for uranium fires rather than the factors in Table 1.

The amount of uranium that becomes airborne from burning uranium chips is estimated on the basis of experiments conducted by Napier (1984). These tests indicated that the amount airborne for drained chips was about 0.0033%. Drained chips have about 15 to 30 wt % water adhering to the chips. The amount airborne was much higher (0.3 to 0.9% of the amount burned) when the chips were ignited in contact with a pool of water. It is believed that the smaller value for drained chips is due to the absence of a gaseous combustion product and minimal water vapor to carry away the UO, solid combustion product from the burning surface. With the larger amount of water, there is sufficient water vapor to entrain UO2 particles and thereby increases the amount of material airborne. However, if there is sufficient water to quench the fire, the total amount of UO2 airborne will be smaller due to less uranium being burned. Thus, the worst case would be an attempt to fight a uranium fire with a liquid but the amount is insufficient to quench the fire. The time to completely bum 30 to 40 kg of chips was about 2 to 4 minutes.

If burning chips are in contact with water or other liquid, but the amount of liquid is insufficient to quench the fire, a value of 1.04 is recommended for the fraction airborne. This is an upper bound to Napier's results. If burning chips are dry or have less than 15 wt % water adhering to the chips, a value of 0.0033 % is recommended. If the burning chips are near (but not in) a hydrocarbon fire, which may supply a significant gas flow, some intermediate value is appropriate. Eased on engineering judgment, the recommended value is 0.033 % (a factor of 10 greater than the dry value). Since the chips bum rapidly, an instantaneous release can be assumed. Alternatively, the rate corresponding to burning 40 kg in 2 minutes (about 300 g/s times the corresponding fraction airborne) can be assumed for a 2-minute duration. In either case, no quenching should be assumed unless it can be justified.

The amount airborne from burning uranium chunks is based on a release factor for �Burning Radioactive Pyrophoric Metal� presented by Ayer et al. (1988, Table 4.2, p. 4.9). The value is 8.9 x 101 percent/s and is assumed to apply to large chunks of dry, burning metal with no significant gas flow to carry away UOZ particles. If the burning uranium part is in contact with a liquid, but the amount of liquid is insufficient to quench the fire, the above rate should be increased by the ratio of wet to dry chips from Napier's experiments (0.0093 - 0.0000333 = 279 or 1000 to be conservative) to give a value of about 0.0089 percent/s. If the burning metal is near, but not in, a hydrocarbon fire, a value of 8.9 × 10-1 percent/s is assumed (a factor of 10 greater than the Ayer et al. value). Since these rates are relatively slow, the fire is assumed to continue for 30 min which is an estimate of the response time for the fire department to arrive and extinguish the fire. This is equivalent to a steady, continuous release over 30 minutes.

Evaporation from Spilled Liquids

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There is an upper limit to the air concentration of a gas coming from an evaporating liquid and this expression is given here. It assumes (1) the liquid covers a large surface area(tens of square meters) and there is a large enough quantity of liquid to keep the surface covered during the time of interest, (2) the region of interest is enclosed and isolated from mixing with the surrounding environment, and (3) the air within the region itself is well mixed. With these assumptions, the maximum (equilibrium) concentration in air can be estimated by

RTpMC WE = (3)

CE is the equilibrium air concentration of the gas, g/m'

p is the partial pressure of the material, mmHg

M., is the molecular weight of the material, g/mole

R is the gas constant, 0.062363 m' mmHg/(°K mole)

T is the absolute temperature, °K.

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ATMOSPHERIC TRANSPORT OF AIRBORNE MATERIALS

Atmospheric transport analysis provides estimates of the time-weighted, average concentration and the concentration-time integral of airborne materials at receptor (people) locations. These quantities are used to assess the health-related consequences of the release on people and are related by

∫=TF

TBi dttCI )( (4)

MtTBTF += (5)

AtIC = , if tM ≤ tA

MtIC = , if tM > tA (6)

I is the concentration time integral, g sec/m3

Ci is the air concentration of the material as a function of time, g/m3

TB is the time the exposure begins, sec

TF is the time the exposure ends, sec

tM is the duration of the exposure, sec

C is the time-weighted, average concentration of the material, g/m3

tA is the averaging time interval, sec.

The time the- exposure begins is usually selected to maximize the concentration-time integral if this time is within the bounds of the scenario.

At distances close to the release (within about 10 meters), the transport is strongly influenced by the geometry of the release and the local air currents. At distances far from the release (greater than about 50 meters), these factors have a diminished effect while larger-scale wind and the atmospheric stability become dominant.

Close-in Estimates For Small Enclosures

If the release takes place within a relatively small enclosure (less than about 1000 ms), the airborne material is assumed to mix instantaneously and homogeneously with the volume of air within this enclosure. It is assumed that initially, people within the enclosure would be aware of the release and would not be immediately incapacitated by the accident. Therefore, they would be exposed only during the time it takes them to leave the enclosure. These assumptions avoid considering many of the local effects.

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The concentration-time integral for an instantaneous release is given by

MtVFQI = (7)

VF is the volume of air within the enclosure, m3.

For a constant-rate release, the maximum value of the concentration-time integral occurs if the exposure begins after all the material is released (r 5 TB). This is equivalent to Equation 7 with the product of dQldt and r replacing Q. In general, the concentration-time integral for a constant-rate release is given by

( )TBTFdtdQt

VFI M +

= 5.0

, for TF ≤ τ

( )2225.0 TBTFdtdQ

VFI −−

= ττ , for TB < τ < TF

MtdtdQ

VFI

= τ

, for τ ≤ TB (8)

Section A.5-11.1 of the Life Safety Code (NFPA, 1988, Page G-7) implies that a person can evacuate an area at a rate of 5 to 7.5 ft/sec (1.5 to 2.3 m/sec). A reasonably conservative estimate of exposure time would be the distance to the nearest exit, divided by the smaller escape rate (1.5 m/sec.).

Close-in Estimates For Large Enclosures and Outdoors

If the release takes place within a large enclosure, instantaneous mixing cannot be assumed. A model based on a turbulent diffusion mechanism is recommended and is described by Bloom (1993). The model assumes simple gas dispersion (no chemical reactions, neutral buoyancy) with no effects of nearby structures (wakes or downwash). The model is also applicable to small particles (less than 10 microns). The source is either a point or a semi-circle that lies in the Y-Z plane and diffusion is assumed to be restricted by solid boundaries (vertical at X=0 and horizontal at Z=0) to the upper-right quadrant (X Z0, -oe < Y < oo, Z z0). The semicircular source encompasses the area given by Yz+Z2 5 r2. X is the horizontal coordinate in the downwind direction, Y is the horizontal coordinate in the crosswind direction, and Z is the vertical coordinate. This model and models for explosive releases and particle deposition have been combined into a QuickBASIC program (INEXPLC.BAS) and its PC executable form (INEXPLC.EXE). The report and these programs (on a disk which includes sample input and output files) are available from S.G. Bloom (Ext 4-6638). Figure I is the sample input and output files for the INEXPLC code.

People in the large enclosure would probably not be immediately aware that an accident occurred nor would they know that they were in the path of a toxic cloud. Consequently, they could be exposed to the entire cloud resulting from an instantaneous release and this conservative assumption (tw -+ m) is usually used. For a constant-rate release, the exposure time is the time required to alert/evacuate people, which may range from a few minutes up to an hour.

For distances greater than 2 meters from the source, the turbulent diffusion model is

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( )

+

−−=F

AF s

rUrQI

1exp12

2π (9)

( ) ( )∑=

=

+

−+

=1

0 1exp

11j

j j

j

jjzyP s

HssAUA

QIπ

(10)

zy

A AArr

2

= , 2

=

yA A

XX , A

AF X

rs += 1 (11)

( )2

224

Zyj A

jZHHZAYH +−+

= ,

A

jj X

Hs += 1 (12)

IF is the infinite-time, concentration-time integral close to a finite-area source, g sec/m3

IP is the infinite-time, concentration-time integral close to a point source, g sec/m3

Q is the amount of material released to the air, g

r is the effective radius of the finite-area source (area is 0.5πr2), m

U is the velocity of the air carrying material from the source in the X direction, m/sec

X is the downwind distance of the receptor from the release (positive values only), m

Y is the horizontal distance of the receptor measured from the X-axis (all values), m

Z is the vertical distance of the receptor measured from the X-axis (positive values only), m

Ay, Az are dispersion parameters in the Y and Z directions, respectively, m

H is the vertical position (positive values) of the point source measured from the X-axis, m

j is a counting variable with values 0 and 1

The dispersion model for the finite-area source applies only along the X-axis (the line Y=Z=O). Values on this line are the maximums at specific downwind locations for the finite-area diffusion model. The model for a point source applies at any location within the upper-right quadrant except right at the source where the value becomes infinite. For a constant rate release over a finite duration, Q is replaced by the smaller of (τ dQ/dt) or (tM dQ/dt).

Unless there is a forced ventilation system in operation, it is often difficult to assign an air velocity (U) for dispersion within a large enclosure. Air currents are usually present even in enclosures with no apparent airflow. In general, air speeds less than I m/sec are not noticeable and it is recommended that a tenth of this value (0.1 m/sec) be used for U if no other value is available. The direction of U should be such to maximize the potential consequences. For outdoors applications, U is usually the wind speed; however, if the outdoor release is in a sheltered area a mirunal value of 1 m/sec may be more appropriate.

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For H=0 (ground-level source), the value of I, along the line through the source (the X-axis) will always be larger than the corresponding IF value at a specific downwind (X) location but the difference between the two values decreases with increasing X. However, the value of I, off the X-axis (the line Y o 0 and/or Z > 0) may be smaller than the corresponding IF value. For H > 0 (elevated source), the value of I, may be smaller than the corresponding IF value even along the line through the source (Y=0, Z=H) except very close to the source. Since the finite-area model is only applicable along the X-axis, the recommended value to use for I for a-receptor and/or a source off this line is the smaller of IF and Ip.

Large Distance Estimates

When the ratio of source radius to downwind distance is small enough, the finite-area source becomes indistinguishable from the point source and Equation 10 be should be used for this region. Equation 10 is applicable for r� 5 0.04 (see Equation 11) and the maximum value of I, occurs for Y=Z=0 and s; = l. The value of s; approaches 1 for large downwind distances {large X) and, for si=1, Equation 10 is equivalent to expressions given in Slade (1968, p 403 to 404). Therefore, Equation 10 provides a smooth link between close-in and large-distance estimates.

Recommended Dispersion Parameters

The recommended dispersion parameters are given by Bloom, (1992) and can be expressed as

XAA zy 175.0, ≈ , for small X for all Stability classes

( )nzy bX

aXAA+

=0.1

, , n=0, ½, 1 for large X

a, b, n are empirical coefficients in the expressions recommended by Briggs for constant-rate releases, level ground, and open-country conditions (see Table 2).

Values for AY and Az should be computed using both of the above expressions and the larger of the two values should be used.

For releases with receptors at the same elevation as the release, F stability will always yield the highest concentrations and concentration-time integrals. For all stability classes, these values decrease with increasing distance from the release. For releases with receptors at an elevation different from the release, these values will increase with distance close to the release, reach maximum values at some distance (depending on the difference in elevations and the stability class), and then decrease with increasing distance. Based on recent guidance from DOE (e.g., DOE-STD-1027-92), the use of F stability is considered to be too conservative, and inconsistent with the meteorology typically used for chemical dispersion. In DOE-STD-1027-92, DOE used a more typical chemical dispersion meteorology such as D stability at 4.5 mlsec, a value used for comparison by NRC and used as the basis for dispersion by the Department of Transportation for assigning evacuation zones around chemical spills. For facility classification, the analyst should use D stability with a wind speed of approximately 3.0 mlsec.

Examination of suggested values of dispersion coefficients for instantaneous releases (Slade, 1968, pp 173-175) indicates that a rough approximation for the instantaneous vertical dispersion coefficient is to set it equal to the corresponding continuous value. It also implies that the instantaneous values for the crosswind, horizontal coefficients are about equal to half the horizontal continuous value. However, the accuracy of any dispersion model is generally poorer than a factor of two so that any correction for release time is not warranted.

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Other Methods

There are other more sophisticated and complicated methods, which may provide better estimates of atmospheric transport but they are beyond the scope of this course. Wind tunnel tests, using a scaled physical model of a facility, have been used extensively to estimate close-in transport and the effects of nearby buildings and other obstacles. The above models do not include effects of buoyancy, phase changes, or chemical reactions, which may significantly impact the results. A model, which approximately incorporates these effects, is available if needed (Bloom, et al, 1989). If detailed data are available on the wind field that is likely to occur during an accident, a puff model (e.g., AFTOX) may be appropriate since such a model allows the gas to more closely follow a trajectory dictated by the wind field. If you have any doubts about the applicability of the simple, �first pass� models, consult either S.G. Bloom or R.A. Just.

Table 2. Formulas for Estimating Dispersion Coefficients

Stability Category Ay

A (0.22 X) (1.0 + 0.0001 X)'� 7 (0.20 X)

B (0.16 X) (1.0 + 0.0001 X)'�n (0.12 X)

C (0.11 X) (1.0 + 0.0001 X)'�n (0.08 X) (1.0 + 0.0002 X7112

D (0.08 X) (1.0 + 0.0001 X)'�n (0.06 X) (1.0 + 0.0015 X7�2

E (0.06 X) (1.0 + 0.0001 X)'�n (0.03 X) (1.0 + 0.0003 Xr�

F (0.04 X) (1.0 + 0.0001 X)-�n (0.016 )) (1.0 + 0.0003 X7�

Notes: Reference is Hanna et. al., 1982, Table 4.5, p 30. A,, and Ax are cross-wind horizontal and vertical dispersion coefficients, respectively, m. Values are for continuous

releases, level ground, and open-country conditions. X is the downwind distance, m.

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Figure 1. LISTING OF SAMPLE INPUT AND OUTPUT FOR THE INEXPLC CODE

Input

BEOC.OUT for a Circular Source

1,10,.5,1000,1.0,0 1,4,100 10,.005,0 100,.1,0 100,10000 1.0,0.,0. 5.,1.0,1.0 10.,1.0,2.0 50.,2.0,10. 100.,5.0,10. 500.,5.0,10. 1000.,5.0,10. 0.,0.,0. for a Circular Source 1,0,.5,100,1.0,0 -1,4,100 0,1.0 1.0,0.,0. 5.,1.0,1.0 10.,1.0,2.0 50.,2.0,10. 100.,5.0,10. 500.,5.0,10. 1000.,5.0,10. 0.,0,0

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Output

DISPERSION ESTIMATES for a Circular Source

QT(g org/s) = 1000, V(m/s)= 1 , ISTAB = 1, H(m) = 10

R(m) =.5 , PSI(mic) = 10 , PSI(mic) = 100 ,

NPCL =1, VD(m/s) =.005 , VD(m/s) =.1 ,

S =4 ,

PSIG(mic) = 100 FR =.0483604

FR =.4516395

TNT(g) = 100 , DIRT(g) =10000 , DURT(s) = 0

X (m) Y (m) Z (m) C(mg/m3) DS (mg s/m3) PSI(mic) 1.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 1.000E+01 1.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 1.000E+02 1.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 1.000E+05 5.000E+00 1.000E+00 1.000E+00 0.000E+00 0.000E+00 1.000E+01 5.000E+00 1.000E+00 1.000E+00 0.000E+00 0.000E+00 1.000E+02 5.000E+00 1.000E+00 1.000E+00 0.000E+00 0.000E+00 1.000E+05 1.000E+01 1.000E+00 2.000E+00 3.546E-40 1.064E-37 1.000E+01 1.000E+01 1.000E+00 2.000E+00 3.666E-39 1.100E-36 1.000E+02 1.000E+01 1.000E+00 2.000E+00 7.332E-39 2.200E-36 1.000E+05 5.000E+01 2.000E+00 1.000E+01 8.701E-01 2.610E+02 1.000E+01 5.000E+01 2.000E+00 1.000E+01 8.995E+00 2.699E+03 1.000E+02 5.000E+01 2.000E+00 1.000E+01 1.799E+01 5.397E+03 1.000E+05 1.000E+02 5.000E+00 1.000E+01 2.315E-01 6.944E+01 1.000E+01 1.000E+02 5.000E+00 1.000E+01 2.393E+00 7.179E+02 1.000E+02 1.000E+02 5.000E+00 1.000E+01 4.786E+00 1.436E+03 1.000E+05 5.000E+02 5.000E+00 1.000E+01 2.492E-02 7.475E+00 1.000E+01 5.000E+02 5.000E+00 1.000E+01 1.508E-01 4.525E+01 1.000E+02 5.000E+02 5.000E+00 1.000E+01 2.902E-01 8.707E+01 1.000E+05 1.000E+03 5.000E+00 1.000E+01 8.187E-03 2.456E+00 1.000E+01 1.000E+03 5.000E+00 1.000E+01 1.265E-02 3.796E+00 1.000E+02 1.000E+03 5.000E+00 1.000E+01 1.760E-02 5.279E+00 1.000E+05

DISPERSION ESTIMATES for a Circular Source

QT(g or g/s) = 100, V(m/s) =1 , ISTAB= 1 , H(m)= 0 R(m) =.5 , NPCL=1 , S =4 , PSIG(mic)= 100

TNT(g) = 0 , DIRT(g) = 1 , DURT(s) = 0 X (m) Y (m) Z (m) C(mg/m3) DS(mg s/m3) PSI(mic) 1.000E+00 0.000E+00 0.000E+00 8.318E+02 2.495E+05 0.000E+00 5.000E+00 1.000E+00 1.000E+00 1.081E+00 3.243E+02 0.000E+00 1.000E+01 1.000E+00 2.000E+00 1.051E-01 3.154E+01 0.000E+00 5.000E+01 2.000E+00 1.000E+01 3.651E-13 1.095E-10 0.000E+00 1.000E+02 5.000E+00 1.000E+01 6.768E-07 2.030E-04 0.000E+00 5.000E+02 5.000E+00 1.000E+01 2.687E-01 8.061E+01 0.000E+00 1.000E+03 5.000E+00 1.000E+01 1.610E-01 4.830E+01 0.000E+00

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15

CONSEQUENCES TO THE RECEPTOR

There are several measures that can be used to assess the consequences of an accident involving the release of a toxic material. Many organizations involved in industrial health (e.g., NIOSH, 1985; ACGIH, 1989), publish values of air concentrations that are considered to cause no significant health effects. However, most of these published values apply to long-term, chronic exposures and would not be applicable to accident situations.

For screening purposes, it is acceptable to use the IDLH concentration (NIOSH, 1985) as the boundary between irreversible and reversible health effects. A tenth of this value may be used as the boundary between reversible and negligible health effects. For release durations less than five minutes, the averaging time is taken to be five minutes for computing a time-averaged concentration for comparison with the IDLH value. A time period is selected to give the highest 5-minute average. The time-averaged concentration is computed using Equation (5), (10), (12), or (14).

If the concentration to produce a specific health effect can be specified as a function of exposure time, an alternative approach should be used. For example, ten Berge et al. (1986) determined that the lethal concentration (LC50) is proportional to TM'� where n is generally greater than 1.0. Their results for n (mean value and 95 percent confidence limits) are summarized in Table 3 for 11 irritant and 9 systemically acting gases and vapors. Table 3 also includes the IDLH values, if available, for these gases and vapors. The recommended approach is to set t� = tM in Equation (5), (10), (12), or (14) and compare the resulting average concentration with the IDLH concentration scaled by ti�'. Concentrations equivalent to the IDLH were calculated in this manner, using the mean value of n, for exposure times of 2, 5, 10, and 15 minutes. The IDLH is defined as being applicable to a 30-minute exposure. Consequently, the IDLH equivalent for a 2-minute exposure period is the IDLH multiplied by (2130). The results of these calculations are also given in Table 3. Using the mean value of n is reasonable for facility classification but, for a Safety Analysis Report (SAR), it is more appropriate (and conservative) to use the 95% confidence limit that yields the lower concentration (i.e., the high limit of n for exposures less than 30 minutes and the low limit for exposures greater than 30 minutes).

If actual information is available on the boundary between irreversible and reversible health effects, and the boundary between reversible and negligible health effects, this information should be used instead of the IDLH values. For example, Just and Emler (1984) report air concentrations of soluble uranium, as functions of exposure time, that result in health effects due to chemical toxicity. These values may be conservatively applied to insoluble uranium. For exposures less than 30 minutes, no health effects occur at concentration time integrals less than 650 mg min/M3 (39 g sec/n-?), possible mild (reversible) health effects occur at concentration time integrals between 650 mg minim' and 1,250 mg minim' (75 g sec/d), renal injury occurs at concentration-time integrals greater than 1,250 mg minim', and the value for 50 percent lethality is 35,000 mg min/m3 (2,100 g sec/m3).

The use of the IDLH (or an equivalent value) is appropriate for HSM when no other measure of health effects is readily available. For SAR applications, an Industrial Hygienist or Toxicologist should be consulted and the IDLH (or its equivalent) should be used only if that was their reconunendation. J. T. Jankovic of Central Safety & Health Organization should be contacted for information on specific toxic materials.

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Table 3. Exponent for Variation with Exposure Time

Gas or vapor. IDLH (ppm) n

95% Confidence limits on n

IDLH, Equivalent for Different Exposure Times

Local Irritants 2 min 5 min 10 min 15 min

Ammonia 500 2 1.6 to 2.4 1936 1225 866 707

Hydrogen Chloride 100 1 0.7 to 1.3 1500 600 300 200

Chlorine Pentafluoride 2 1.4 to 2.6

Nitrogen Dioxide 50 3.5 2.7 to 4.3 108 83 68 61

Chlorine 30 3.5 2.5 to 4.4 65 50 41 37

Perfluoro-isobutylene 1.2 1.1 to 1.4 -

Crotonaldehyde 400 1.2 1.1 to 1.3 382 713

Hydrogen Fluoride 30 2 1.2 to 2.8 116 73

Ethylene-imine 1.1 0.8 to 1.3 52 42

Bromine 10 2.2 2.0 to 2.4 34 23

Dibutylhexa- methylenediamene 1 0.6 to 1.4 16 14

Systemic Action

Hydrogen Cyanide 50 2.7 1.8 to 3.7 136 97 75- 65

Hydrogen Sulfide 300 2.2 1.6 to 2.7 1027 677 494 411

Methyl t-Butyl Ether 2 1.0 to 2.9

Chlorobromomethane 5000 1.6 1.4 to 1.8 27166 15322 9935 7711

Ethylene Dibromide 400 1.2 1.1 to 1.2 3821 1780 999 713

Tetrachloroethylene 500 2 1.4 to 2.6 1936 1225 866 707

Trichloroethylene 1000 0.8 0.3 to 1.4 29520 9391 3948 2378

Carbon Tetrachloride 300 2.8 1.9 to 3.7 789 569 444 384

Acrylonitrile 500 1.1 1.0 to 1.2 5863 2549 1357 939

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17

The consequences of radionuclide releases are usually expressed in terms of radiation doses (rem or millirem). Radiation exposures can result from radionuclides existing outside the body (external dose) and those that have been inhaled, ingested, or absorbed (through the skin) inside the body (internal dose). External exposure ceases when the person leaves the contaminated area, removes any contaminated clothing, and/or washes any contamination from his skin. However, internal exposure will continue until the body can rid itself of the radionuclide. For long-lived radionuclides that cannot be readily cleared from the body, the exposure can last for the remaining life of the individual. Therefore, a radionuclide release is likely to lead to higher internal doses than external doses.

For radionuclides released to the air, inhalation is the principal pathway for entering the body. An expression for calculating the internal radiation dose due to inhalation is

ISBDD AFs = (15)

Ds is the 50-year committed effective dose equivalent (C.E.D.E.), rem

B is an inhalation rate, m3/s

DF is the radiation dose factor, rme/Ci

SA is the specific activity of the radionuclide, Ci/g

The C.E.D.E. is a measure of the equivalent radiation dose to the whole body that is incurred over a 50-year period following inhalation of the radionuclide. The dose factors are tabulated in DOE/EH-0071 (1988b). Unless there is specific information to indicate the solubility class of the radionuclide (Class D, W, or Y), the highest dose factor should be used. The inhalation rate usually assumed is 1.2 m'/h (0.000333 m3/s) which may be typical for moderate exertion. For a pure radionuclide, the specific activity can be calculated from

( )HWA TM

S510578.3 ×= (16)

TH is the half-life of the radionuclide, years.

For most accident scenarios at Y-12 and the gaseous diffusion plants, the principal radioactive material is uranium consisting of varying amounts of 2�U, 'U, and 'U. The specific amounts of each radionuclide depend on whether the uranium is the naturally-occurring material, enriched in IU by the gaseous diffusion process, or the tads of this process which are depleted in =�U. Since the half-life of a' U (2.45 × 103 years) is much shorter than that of IU (7.04 × 101 years) or z� U (4.47 × 10 years), most of the radioactivity is due to the 9''U. In the gaseous diffusion process, z'° U is enriched or depleted along with U which is the key isotope for the various uses of uranium. An empirical expression relating the specific activity of uranium to the percent of 'U has been presented by Rich et al. (1989) and is

( ) 62 100034.038.04.0 −×++= EES A (17)

E is the weight percent of U-235

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18

Naturally-occurring uranium contains 99.2745 weight percent �U, 0.72 percent U-235, and 0.0055 percent z�U. Depleted uranium contains about 0.20 percent�' U. Enriched uranium occurs with different percentages of IU at the plants and the percent of U must be specified to use Equation (17).

Since the radiation dose factors for the above three isotopes of uranium are similar (1.3 × 10` rem/Ci for z�U and 1.2 × 10 rem/Ci for � U and “s U), the value for' U can be conservatively used with Equations (15) and (17) to estimate internal radiation doses involving uranium releases. In the future, uranium enriched by the AVLIS process may be prevalent. The AVLIS process is more specific in enriching IU and Equation (17) may no longer apply.

There are also dose factors to estimate the external dose rate from beta- and gamma-emitting radionuclides to a person in the vicinity of an infinite, contaminated plane and submerged in an infinite, contaminated cloud. These external dose rate factors are tabulated in DOE/EH-0070 (1988a). The immersion dose depends on the air concentration but the plane dose requires an estimate of the surface concentration (Ci/mz) on the ground, which may be difficult to estimate. However, for most situations involving uranium, the radiation is due to alpha particles, which contribute a negligible external dose. The main radiation concern with uranium is the potential inhalation and/or ingestion and the resulting internal dose, which can be calculated using Equations (15) and (17). If a situation arises requiring an external dose calculation, consult with S. G. Bloom.

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19

REFERENCES

1. ACGIH, 1989, Threshold Limit Values and Biological Exposure Indices for 1989-1990, American Conference of Governmental Industrial Hygienists.

2. J. E. Ayer, A. T. Clark, P. Loysen, M. Y. Ballinger, J. Mishima, P. C. Owczarski, W. S. Gregory, and B. D. Nichols, Nuclear Fuel Cycle Facility Accident Analysis Handbook, NUREG-1320, U.S. Nuclear Regulatory Commission, Office of Nuclear Material Safety and Safeguards, Washington, D.C, 1988.

3. S. G. Bloom, R. A. Just, and W. R. Williams, A Computer Program for Simulating the Atmospheric Dispersion of UF6 and Other Reactive Gases Having Positive, Neutral, or Negative Buoyangy, K/D-5694, Martin Marietta Energy Systems, Inc., Oak Ridge Gaseous Diffusion Plant, 1989.

4. Bloom, S.G., Atmospheric Transport Analysis used in Hazard Screening Methodology, paper (92-WA/SAE 5) presented at the session on Safety Engineering and Risk Assessment (SERAD) at the Winter Annual Meeting of the American Society of Mechanical Engineers (November 8-13, 1992) in Anaheim, California.

5. Bloom, S. G. Models for Close In Atmospheric Dispersion, Explosive Releases, and Particle Deposition, ORNLITM-12452, Martin Marietta Energy Systems, Inc., Oak Ridge National Laboratory, Oak Ridge, TN., 1993.

6. U.S. Department of Energy, External Dose Rate Conversion Factors for Calculation of Dose to the Public, DOE/EH-0070, U.S. Department of Energy, Assistant Secretary for Environment, Safety and Health, Washington, D.C, 1988

7. U.S. Department of Energy, Internal Dose Conversion Factors for Calculation of Dose to the Public, DOE/EH-0071, U.S. Department of Energy, Assistant Secretary for Environment, Safety and Health, Washington, D. C, 1988.

8. S. R. Hanna, G. A. Briggs, and R. P. Hosker, Jr., Handbook on Atmospheric Division, DOE/TIC11223, U.S. Department of Energy, Office of Energy Research, Washington, D.C., 1982

9. R. A. Just and V. S. Emler, Generic Report on Health Elects for the U.S Gaseous Diffusion Plants, K/D 5050, Section VIII, Part 1, Martin Marietta Energy Systems, Inc., Oak Ridge Gaseous Diffusion Plant, Oak Ridge, TN., 1984.

10. J. M. Napier, Release of Uranium to Air During Oxidation of Uranium Chips, internal correspondence to I. Darling, July 9, 1984, Martin Marietta Energy Systems, Inc., Y-12 Plant, Oak Ridge, TN.

11. National Fire Protection Association (NFPA), 101-1988 Life Safety Code, 1988.

12. NIOSHIOSH.4 Guide to Chemical Hazards, National Institute for Occupational Safety and Health/Occupational Safety and Health Administration, NIOSH, 1985.

13. B. L. Rich, S. L. Hinnefeld, C. R. Lagerquist, W. G. Mansfield, L. H. Munson, E. R. Wagner, and E. J. Vallario, Health Physics Manual of Good Practices for Uranium Facilities, EGG-2530, EG&G Idaho, Inc., Idaho National Engineering Laboratory, Idaho Falls, ID, 1988.

14. D. H. Slade, Meteorology and Atomic Energy, TIC-24190, U.S. Atomic Energy Commission, Office of Information Services, Washington, D.C., 1968.

15. W. F. ten Berge, A. Zwart, and L. M. Appelman, Concentration-Time Mortality Response Relationship of Irritant and Systemically Acting Vapours and Gases. Journal of Hazardous Materials, Vol. 13, pp. 301 to 309, 1986.

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ATTACHMENT 2

USE OF EMERGENCY RESPONSE PLANNING GUIDELINES

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3

The American Industrial Hygiene Association has developed Emergency Response Planning Guidelines (ERPGs) for emergency response applications. The ERPGs are widely accepted endpoints for evaluating the consequences of accidental chemical exposures. However, ERPGs only currently exist for approximately 50 chemicals. Therefore, ERPG alternatives must be used for many chemicals. The DOE-HQ Office of Emergency Planning and Operations Subcommittee on Consequence Assessment and Protective Actions (SCAPA) has developed the following hierarchy of alternative criteria if ERPGs are not available

ERPG1 Source PEL-STEL OSHA TLV-STEL ACGIH TLV-TWA x 3 ACGIH ERPG2 Source EEGL (60-min) NAS LOC EPA/FEMA/DOT PEL-C ACGIH TLV-C ACGIH TLV-TWA x 5 ACGIH ERPG-3 Source EEGL (30 min) NAS IDLH NIOSH

The definition of the acronyms used above are provided below.

AGENCIES

ACGIH American Conference of Governmental Industrial Hygienists AIHA American Industrial Hygiene Association EPA Environmental Protection Agency FEMA Federal Emergency Management Agency NAS National Institute for Occupational Safety and Health NIOSH National Institute for Occupational Safety and Health OSHA Occupational Safety and Health Administration USDOT U. S. Department of Transportation GUIDELINES (Text extracted from memo from Doug Craig, Westinghouse, to the SCAPA chair)

AIHA Terms (developed for emergency response purposes)':

ERPG-1 Emergency Response Planning Guideline 1: �The maximum airborne concentration below which it is believed that nearly all individuals could be exposed for up to 1 hour without experiencing other than mild transient adverse health effects or perceiving a clearly defined objectionable odor.�

ERPG-2 Emergency Response Planning Guideline 2: �The maximum airborne concentration below which it is believed that nearly all individuals could be exposed for up to 1 hour without experiencing or developing irreversible or other serious health effects or symptoms that could impair their abilities to take protective action.�

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ERPG-3 Emergency Response Planning Guideline 3: �The maximum airborne concentration below which it is believed nearly all individuals could be exposed for up to 1 hour without experiencing or developing life-threatening health effects.�

NAS Terms (developed for military use)2:

EEGL Emergency Exposure Guidance Level: �A concentration of a substance in air (as a gas, vapor, or aerosol) that may be judged by DOD to be acceptable for the performance of specific tasks during rare emergency conditions lasting for periods of 1-24 h. Exposure at an EEGL might produce reversible effects that do not impair judgement and do not interfere with proper responses to the emergency�. The EEGL is �a ceiling guidance level for a single emergency exposure, usually lasting from 1 h to 24 h -- an occurrence expected to be infrequent In the lifetime of a person�.

CEGL Continuous Exposure Guidance Level: �CEGLs are ceiling concentrations designed to avoid adverse health effects, either immediate or delayed, of more prolonged exposures and to avoid degradation in crew performance that might endanger the objectives of a particular mission as a consequence of continuous exposure for up to 90 d�.

SPEGL Short-Term Public emergency Guidance Level: �The SPEGL is defined as a suitable concentration for unpredicted, single, short-term, emergency exposure of the general public. In contrast to the EEGL, the SPEGL takes into account the wide range of susceptibility of the general public. This includes sensitive populations - such as children, the aged, and persons with serious debilitating diseases�.

OSHA Terms (developed for occupational safety)':

PEL Permissible Exposure Limit: Although the term PEL is not used in the �Final Rule Limits Columns� of Table Z-1-A and Table Z-2 (29 CFR 1910.000, July 1, 1990), it was used in the �Transitional Limits�. It is also used in the compound-specific rules for various substances, e.g. #1910.1018 (Inorganic arsenic), #1910.1028 (Benzene), #1910.1045 (Acrylonitrile), #1910.1047 (Ethylene oxide), etc.

PEL-TWA Time-Weighted Average: The employee's average airborne exposure in any 8-hour work shift of a 40-hour workweek, which shall not be exceeded. This is to be computed from the equation:

( )8

nnbbaa TCTCTCE Κ++=

where C is the concentration during any period of time T (in hours) where the concentration remains constant

PEL-STEL Short-Term Exposure Limit: The employee�s 15-minute time weighted average exposure that shall not be exceeded at any time during a work day unless another time limit is specified.�

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PEL-C Ceiling: �The employee�s exposure which shall not be exceeded during any part of the work day�. If necessary from a monitoring point of view, C may be assessed as a 15-minute time,weighted average.

EPA Term (developed for emergency planning)4

LOC Level of Concern: The concentration of an extremely hazardous substance in air above which there may be serious Irreversible health effects or death as a result of a single exposure for a relatively short period of time.� (Also used by FEMA and USDOT)

ACGIH Terms (developed for workplace safety)5

TLV-TWA Threshold Limit Value Time Weighted Average: �The time weighted average concentration for a normal 8-hour workday and a 40-hour workweek, to which nearly all workers may be repeatedly exposed, day after day, without adverse effect.�

TLV-STEL Threshold Limit Value—Short-Term Exposure Limit: �The concentration to which workers can be exposed continuously for a short period of time without suffering from 1) irritation, 2) chronic or irreversible tissue damage, or 3) narcosis of sufficient degree to increase the likelihood of accidental injury, impair self-rescue, or materially reduce work efficiency, and provided that the daily TLV-TWA is not exceeded.� �A TLV-STEL is ... a ... 15-minute TWA exposure which should not be exceeded at any time during a workday even if the 8-hour TWA is within the TLV-TWA. Exposures above the TLV-TWA up to the STEL should not be longer than 15 minutes and should not occur more than four times per day. There should be at least 60 minutes between successive exposures in this range.�

TLV-C Threshold_ Limit Value – Ceiling: �The concentration that should not be exceeded during any part of the working exposure.� � ... if instantaneous monitoring is not feasible, then the TLV-C can be assessed by sampling over a 15-minute period except for those substances that may cause immediate irritation when exposures are short.�

NIOSH Term (developed for respirator use)6:

IDLH Immediately Dangerous to Life or Health: �The maximum concentration from which, in the event of respirator failure, one could escape within 30 minutes without a respirator and without experiencing any escape-impairing (e.g. severe eye irritation) or irreversible health effects.�

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REFERENCES

1. ERPGs: Concepts and Procedures for the Development of Emergency Response Planning Guidelines (ERPGs). American Industrial Hygiene Association ERPG Committee. December 1989. [New data sets issued as they are developed.)

2. Emergency and Continuous Exposure Guidance Levels for Selected Airborne Contaminants, V 1 -7. COMMITTEE ON TOXICOLOGY. Board on Toxicology and Environmental Health Standards, Commission on Life Sciences, National Research Council, National Academy Press, Washington, DC. (1985).

3. Code of Federal Regulations: Labor: CFR29: PARTS 1900 TO 1910, Revised as of July 1, 1988. # 1900-1000, Subpart Z - Toxic and Hazardous Substances, pp 6 - 33 (1900).

4. Technical Guidance for Hazard Analysis. Emergency Planning for Extremely Hazardous Substances. U.S. Environmental Protection Agency, Federal Emergency Management Agency; and U.S. Department of Transportation, USGPO 1991517-003/47004, December 1987.

5. 1992 -1993 Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. American Conference of Governmental Industrial Hygienists, Cincinnati, OH (1992).

6. NIOSH POCKET GUIDE TO CHEMICAL HAZARDS. U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health Washington DC (1990).

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ATTACHMENT 3

REACTIVE MATERIALS AND INCOMPATIBLE CHEMICALS

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This appendix originally included attachments 1 and 2 of Environmental Protection Procedure EPM-12.0. Due to copy quality, Attachment 1 was omitted from this appendix. Information on reactive materials is found in the bottom left corner of Attachment 1. Information on incompatible chemicals is found in Attachment 2, which is included in this appendix.

Hazardous Chemical Reactions

Acetic acid and potassium hydroxide - Potassium hydroxide residue in a catalyst pot reacted violently when acetic acid was added.

Acetone and chloroform - A mixture of acetone and chloroform in a residue bottle exploded. Since addition of chloroform to acetone in the presence of a base will result in a highly exothermic reaction, it is thought that a base must have been in the bottle.

Acetone and sodium hypobromite - An explosion occurred during an attempt to prepare bromoform from acetone by the haloform reaction.

Acetone and sulfuric acid and potassium dichromate - Acetone ignited when it was accidentally splashed into a sulfuric acid-dichromate solution.

Acetone and 1.1.1-trichloroethane - A mixture of 1,1,1-trichloroethane and acetone will undergo a highly exothermic reaction when catalyzed by a base.

Air (liquid) and charcoal - Explosions have occurred when liquid air contacted organic matter. A cracked tube of activated charcoal immersed in liquid air exploded violently.

Air (liquid)-and hydocarbons - Almost any reducing agent and all hydrocarbons can foam explosive mixtures with liquid air.

Alcohol& and hydrogen peroxide and sulfuric acid - Mixtures of alcohol with concentrated sulfuric acid and strong hydrogen peroxide can cause explosions. Mixtures of ethyl alcohol with concentrated hydrogen peroxide for powerful explosives.

Alcohols and hypochlorous acid - Alkyl hypochlorites are violently explosive. They are readily obtained by reacting hypochlorous acid and alcohols either in aqueous solutions or in mixed water-carbon tetrachloride solutions. These materials decompose in the cold and explode on exposure to sunlight or heat.

Alkali metals and boron trifluoride - boron trifluoride reacts incandescently when heated with alkali metals or alkaline earth metals, except magnesium.

Alkali metals and maleic anhydride - Maleic anhydride decomposes explosively in the presence of alkali metals.

Aluminum and ammonium nitrate - A mixture of aluminum powder and ammonium nitrate can be used as an, explosive. A number of explosions in which ammonium nitrate and aluminum were mixed with carbon or hydrocarbons, with or without oxidizing agents, have occurred.

Aluminum and bismuth trioxide - When bismuth trioxide is heated with powdered aluminum, the reduction occurs with explosive violence.

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Aluminum and bromates - A combination of finely divided aluminum with finely divided bromates (also chlorates or iodates) of barium, calcium, magnesium, potassium, sodium, or zinc can be exploded by heat, percussion, or sometimes light friction.

Aluminum and bromine - Bromine vapor reacts with warm aluminum foil with brilliant incandescence. The reaction is vigorous, even at 15°C.

Aluminum and carbon tetrachloride - A bomb containing powdered aluminum and carbon tetrachloride exploded violently when heated to 153°C. A mixture of powdered aluminum and carbon tetrachloride in a ball mill exploded. Impact sensitivity tests have shown that mixtures of carbon tetrachloride and aluminum will detonate.

Aluminum and chlorinated hydrocarbons - When hot vapors contact powdered aluminum, an explosion results. Contact at room temperature with freshly machined chips results in violent reaction.

Aluminum and chlorine - Aluminum powder burns in chlorine, even at 20°C.

Aluminum and chlorofluorohydrocarbons - It has been experimentally determined that mixtures of powdered aluminum with monofluorotrichloroethane or with trifluorotrichloroethane will flash or spark on heavy impact.

Aluminum and chloroform - Chloroform, methyl chloride, and carbon tetrachloride and mixtures of these chemicals explode when in contact with aluminum powder or magnesium powder.

Aluminum and conner oxide - A strong explosion occurred when aluminum was heated with copper oxide. With lead oxide, the crucible was broken in pieces and the doors of the furnace blown off.

Aluminum and fluorochloro lubricants - An explosive reaction occurs with fluorochloro oils or greases in contact with fresh aluminum surfaces under high loads. Examples cited: a spinning aluminum rod under pressure on an aluminum surface; a freshly bored aluminum cylinder under pressure from an aluminum piston; threading an aluminum rod into a dural tube with fluorochloro oil as a lubricant.

Aluminum and iodine - Aluminum powder and iodine in close contact will ignite spontaneously.

Aluminum and iron -oxide - The reaction of powdered aluminum and iron oxide, usually started by burning magnesium, proceeds vigorously, with evolution of intense heat. The mixture is known as �thermite.� The reaction can be initiated by impact between all aluminum objects and a rusty surface.

Aluminum and lead oxides - The reduction of lead oxide by aluminum is violent.

Aluminum and sodium hydroxide - A 2590 sodium hydroxide solution was filtered into a tank trailer thought to be made of mild steel. By the time it was discovered that the tank was made of aluminum, copious volumes of hydrogen were already boiling off.

Aluminum and sulfates - Violent explosions occur when potassium sulfate and sodium sulfate are melted with aluminum. The reduction of barium sulfate and of calcium sulfate is attended by violent explosions.

Aluminum and trichloroethylene - In the presence of dilute hydrochloric acid (0.1 % to 0.2% ), aluminum and trichloroethylene formed aluminum chloride which catalyzed polymerization of the trichloroethylene with a very high release of heat. Under this condition, subsequent oxidation of aluminum fires caused an explosion.

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Ammonium nitrate and contaminant - During the flame cutting of a pipeline plugged with impure ammonium nitrate, the pipe contents exploded violently.

Ammonium nitrate and metals - The reaction of fused ammonium nitrate with powdered metals is often violent and sometimes explosive. Zinc; cadmium, copper, magnesium, lead, cobalt, nickel, bismuth, chromium, and antimony are the metals that reacted in this way.

Ammonium nitrate and organic matter - Ammonium nitrate forms explosive mixtures with organic matter.

Aniline and nitrobenzene and glycerin - In the reaction of these three ingredients to form quinoline, with ferrous sulfate as catalyst, there was too much sulfuric acid and too little water present. The resultant excessive temperature initiated a runaway reaction.

Arsenic and bromates - A combination of finely divided arsenic with finely divided bromates (also chlorates and iodates) of barium, calcium, magnesium, potassium, sodium, or zinc can be exploded by heat, by percussion, and- sometimes by light friction.

Arsenic and chlorine - Arsenic burns spontaneously in gaseous chlorine. With liquid chlorine, arsenic ignites at 33 °C.

Arsenic and potassium nitrate - A mixture of arsenic and potassium nitrate explodes when ignited.

Barium and acids - Barium reacts violently with acids.

Barium and trichlorotrifluoroethane - It has been determined experimentally that mixtures of finely divided barium metal and a number of halogenated hydrocarbons possess an explosive capability.

Barium and water - Barium rapidly decomposes water. The heat of reaction is sufficient that the evolved hydrogen may ignite.

Barium alloys and acids - Alloys containing a substantial proportion of barium react violently with acids.

Barium alloys and water - The reaction is similar to that of barium.

Beryllium and carbon tetrachloride - It has been determined experimentally that a mixture of beryllium powder with carbon tetrachloride will flash or spark on heavy impact. Trichloroethylene will produce the same reaction.

Calcium oxide and water - Addition of water to quicklime has generated temperatures as high as 800°C. Some reports describe the reaction as violent. Ignition of sulfur, gunpowder, wood, and straw by the beat of the quicklime reaction has been reported.

Carbon and oils and air - Fatty oils are spontaneously flammable when distributed in activated carbon. The carbon enormously increases the surface of oil exposed to the air.

Chlorates and acids - All chlorates, when brought into contact with sulfuric acid or certain other strong acids, may give off chlorine dioxide, an explosive gas. With concentrated sulfuric acid, a violent explosion is usual.

Chlorine and acetylene - Acetylene can react explosively with chlorine.

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Chlorine and ammonia - Ammonia plus chlorine (with heat) explodes, due to the formation of extremely sensitive nitrogen trichloride.

Chlorine and benzene - An explosion of benzene vapors and chlorine (inadvertently mixed) was initiated by light.

Chlorine and brass - Brass burns spontaneously in gaseous chlorine.

Chlorine and carbon (activated) - The mixture ignites spontaneously in the dry state.

Chlorine and hydrocarbons - In a chemical process, chlorine inadvertently contacted hydrocarbon vapors at about 6 psig. An explosion ruptured the pipeline.

Chlorine and hydrogen - A mixture of hydrogen and chlorine is exploded by almost any form of energy. Explosive range: 5% to 95%:

Chrmates and hydrazine - Hydrazine is decomposed explosively by chromates and chromic anhydride.

Copper and acetylene - Unstable acetylides form when acetylene is passed over copper that has been heated to form a tarnish of oxide coating. In the presence of wet acetylene and ammonia, copper and brasses down to 6090 copper form explosive acetylides.

Copper and bromates - A combination of finely divided copper with finely divided bromates (also chlorates or iodates) of barium, calcium, magnesium, potassium, sodium, or zinc will explode with heat, percussion, .and sometimes light friction.

Copper and hydrogen sulfide - If a mixture of air and hydrogen sulfide is passed over powdered copper, the mixture may heat to redness.

Cyanides and chlorates - Violent explosion occurs if cyanide salt is melted with nitrite salt. The melt explodes if cyanide plus chlorate or nitrite is heated to 450°C.

Ethyl alcohol and hydrogen peroxide - The addition of alcohols to concentrated hydrogen peroxide forms powerful explosives which can be detonated by shock.

Ferrous oxide and air - Ferrous oxide is spontaneously flammable in air.

Ferrous oxide and nitric acid - When pyrophoric iron oxide is gently warmed with nitric acid, the oxide becomes incandescent.

Fluorine and acetylene - Acetylene and fluorine will react violently.

Fluorine and alkali oxides - The oxides of the alkalies and alkaline earths are vigorously attacked by fluorine gas with incandescence.

Fluorine and ammpnig - Fluorine and ammonia burst into flame.

Fluorine and carbon - Graphitic or crystallized carbon tends to react explosively with fluorine after an intermediate induction period.

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Fluorine and common materials and oxygen - Spill test of 100% liquid fluorine, 30% liquid fluorine in oxygen, and 100% oxygen on various common materials demonstrated the following effects of the fluorine content: asphalt and also crushed limestone (calcium carbonate) burned with sputtering and small flames; JP-4 fuel produced loud rapid explosions and a large fireball; coke burned with a small flame; charcoal burned smoothly with a large brilliant fireball; and rich soil burned with a bright flame.

Fluorine and hydrogen - Fluorine and hydrogen combine with extreme violence. The reactions of most organic compounds with fluorine occur explosively. Even halogenated organic materials burn or explode in a fluorine atmosphere. The reaction with water is violent even at -210°C.

Fluorine and hydrogen sulfide - Fluorine ignites in contact with hydrogen sulfide.

Fluorine and metals - Metals (powdered) are in general attacked by fluorine at ordinary temperatures. If the temperature is raised, nearly all the metals are vigorously attacked with incandescence. Some average ignition temperatures (°F) of various metals in fluorine are: aluminum - higher than 1220, iron - 672, Monel - 396, nickel - 1162, 302 stainless steel - 681., and tungsten - 283.

Fluorine and neoprene - When pieces of neoprene are dropped into liquid fluorine, slight explosions occur and the neoprene burns. Neoprene-covered fiberglass exploded in liquid fluorine.

Fluorine and nitric acid - If fluorine is passed into nitric acid, each bubble of gas is attended by decomposition of the acid and accompanied by flame.

Fluorine and solid nonmetals and oxygen - Numerous nonmetal materials were tested statically on gaseous and liquid fluorine-oxygen mixtures with 50 to 100% fluorine. Substances that burned or reacted violently were: Tygon, nylon, Bakelite, buna N, LS53 and LS63 rubber, Viton A, and polyurethane foam. Under dynamic conditions, i.e., flow and pressure, materials such as Lucite, Teflon, and CPE products (chlorinated polyethylenes) also ignited in fluorine-oxygen mixtures.

Hydrazine and air - Hydrazine may ignite spontaneously while absorbed on porous materials such as earth, asbestos, cloth, or wood unless the heat of the gradual hydrazine-air mixture has a chance to dissipate. Spontaneous ignition can occur with hydrogen peroxide and nitric acid. Contact with many metallic oxide surfaces may lead to flaming decomposition.

Hydrogen and air and platinum - Finely divided platinum and some other metals will cause a mixture of hydrogen and oxygen to explode at ordinary temperatures. If a jet of hydrogen in air impinges on platinum black, the metal becomes hot enough to ignite the gas.

Hydrogen peroxide and acetic acid - Even dilute hydrogen peroxide added to dilute acetic acid and heated will initiate an exothermic reaction with production of peracetic acid, which will explode at 110°C.

Hydrogen peroxide and organic matter - Under certain circumstances hydrogen peroxide is capable of developing an explosive power in excess of its weight equivalent of TNT when mixed with organic compounds; the acetone-hydrogen peroxide system is a good example.

Hydrogen sulfide and nitric acid - Fuming nitric acid reacts incandescently with hydrogen sulfide.

Hydrogen sulfide and soda lime (NAOH and CaO) - The reaction between hydrogen sulfide and soda lime is attended with incandescence in the presence of air; in oxygen, there is a violent explosion. Mixtures of barium oxides with mercurous or nickel oxide also react vigorously with hydrogen sulfide in air, and vivid incandescence or explosions may result.

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Lead and zirconium - An alloy of 10% to 70% zirconium with lead will ignite when struck with a hammer.

Lead oxide and perchloric acid and glycerin - Over a period of time, perchloric acid fumes from a laboratory hood condensed on the cover plate of the exhaust fan, which was sealed with a cement of litharge and glycerin. When a workman tapped the plate with a chisel, a violent explosion caused two injuries and one fatality.

Lithium and air - Lithium is spontaneously flammable in air if heated to 180°C, if the surface of the metal is clean.

Lithium and carbon tetrachloride - There was no reaction when a drop or two of carbon tetrachloride was added to burning lithium. When the quantity was eventually increased to about 25 cc of carbon tetrachloride, a violent explosion occurred.

Lithium and nitric acid - When 15 ml of nitric acid was poured onto 15 grams of lithium in an attempt to dissolve the metal, a small fire started in the flask. In less than a minute, the reaction was so vigorous that burning lithium was thrown upward in the laboratory hood.

Lithium and oxygen - Lithium will burn in air, oxygen, nitrogen, and carbon dioxide. The susceptibility of molten lithium surfaces to spontaneous ignition is increased by the presence of lithium oxides or nitrides. These reactions and the reaction with water are extremely violent at higher temperatures. Contact with halogenated hydrocarbons can produce extremely violent reactions, especially on impact.

Lithium aluminum hydride and air - Lithium aluminum hydride can burn in heated or moist air.

Magnesium and air - Magnesium ribbon or fine shavings can be ignited at air temperatures of about 950°F, and very finely divided magnesium powder has been ignited at air temperatures below 900°F.

Magnesium and beryllium oxide - Oxides of beryllium, cadmium, mercury, molybdenum, and zinc can react explosively with magnesium when heated.

Magnesium and chloroform - When chloroform or methyl chloride (or mixtures of both) contacts magnesium, an explosion occurs.

Magnesium and nitrogen dioxide - Magnesium, phosphorus, or sulfur burns vigorously in nitrogen dioxide.

Magnesium and vhosnhates - A mixture of the two may cause an explosion.

Magnesium and silver nitrate - A mixture of the two ingredients will burst into flame on moistening. The water causes electrochemical exchange between the magnesium and the silver ion. The heat of reaction of this exchange provokes the pyrochemical effect.

Magnesium sulfates - A mixture of the two may cause an explosion.

Magnesium- alloys and air - Magnesium alloy powders containing more than 50�% magnesium readily ignite in air.

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Manganese and aluminum and air - During a fire in an industrial bag filter, a mixture of aluminum and manganese dusts was inadvertently released from the hopper below the bag, and a drastic explosion resulted.

Mercuric nitrate and acetylene - Acetylene forms a sensitive acetylide when passed into an aqueous solution of mercuric nitrate.

Mercuric nitrate and ethyl alcohol - Alcohols should not be mixed with mercuric nitrate, as explosive mercury fulminate may be formed.

Mercuric nitrate and unsaturates. aromatics - Mercuric nitrate reacts with unsaturates and aromatics with violence if given time to generate enough heat.

Mercury and chlorine dioxide - Chlorine dioxide and liquid mercury explode violently.

Nitric acid and ammonia - Ammonia gas burns in an atmosphere of nitric acid.

Nitric acid and anion exchange resins - If hydroxyl-form anion exchange resins are contacted by nitric acid solutions of excessive strength (e.g., 6 molar) rapid heating and resulting gaseous degradation products can pressurize and damage the ion exchange vessel.

Nitric acid and anion exchange resins and dichromate - Dichromate loadings as low as 0.05 gram per cubic centimeter of resin in contact with 7 molar nitric acid can cause a runaway reaction. Ignition temperature is 92 °C and decreases with increasing dichromate loading.

Nitric acid and ethyl alcohol - If a mixture of concentrated nitric acid and ethyl alcohol is stirred, a reaction starts slowly and accelerates to an explosion.

Nitric acid and nitrobenzene - Mixtures of nitric acid and nitrobenzene are detonable, depending upon the amount of water present.

Nitric acid and organic matter - Nitric acid ignites spontaneously with some organic compounds, such as furfuryl alcohol and butyl mercaptan.

Nitric acid and toluene and sulfuric acid - If Conditions are not properly controlled, the reaction of toluene with nitric acid is extremely violent, especially in the presence of sulfuric acid, which takes up the water formed. Part of the hazard is from the formation of nitrocresols, which react and decompose violently on further nitration.

Oxygen and clothing - The normal .2 to 3% oxygen enrichment of air supplied to an air-supplied suit was upset by failure of the air-oxygen mix value so that the enrichment was 68 to 7696. A worker who had disconnected supply and exhaust lines removed his helmet and lighted a cigarette. Apparently a spark from the cigarette lighted his oxygen-saturated underwear.and also the pressure suit.

Oxygen -and ethers - In the presence of oxygen or air, ethers form peroxides which may explode spontaneously with friction or when heated. Isopropyl ether, which had stood on the shelf a long time, exploded when the stuck cap on the bottle wax freed.

Oxygen and tirichloroethylene - The explosion of an oxygen pipe under pressure (400 psi) in a metallurgical factory was apparently due to the remains of trichloroethylene, which was used for the previous cleaning of the pipes. Tests showed it was possible to make a stoichiometric mixture of trichloroethylene and oxygen vapors explode.

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Perchlorates and metals - When perchlorates are mixed with finely divided metals, the mixture may be explosive.

Perchlorates and organic matter - When perchlorates are mixed with finely divided organic matter they may be explosive.

Perchlorates and sulfuric acid - A mixture of the two may cause an explosion.

Perchloric acid - Anhydrous perchloric acid can decompose explosively at atmospheric pressure. On storage, even in the dark, the anhydrous acid becomes discolored owing to decomposition products, e.g., chlorine dioxide, and may explode spontaneously.

Perchloric acid and acetic acid - Explosions involving these materials have occurred in electrolytic polishing baths. The violence in some cases approached that of a true high explosive.

Perchloric acid and alcohols - The contact of hot concentrated perchloric acid with alcohols or cellulose is particularly dangerous.

Perchloric acid_ and charcoal - A drop of anhydrous perchloric acid on charcoal causes a violent explosion.

Perchloric acid and organic matter - Perchloric acid can cause fire or explosion in most organic materials. Example: when bis(2-hydroxyethyl) terephthalate, being refluxed with 5% perchloric acid in ethyl alcohol, was allowed to go to dryness, there was a violent explosion. A similar mixture; containing also ethylene glycol, flashed brightly after 18 hours refluxing. See also the other organic entries under perchloric acid.

Permanganates and acetic acid - Acetic acid or acetic anhydride can explode with permanganates if not kept cold. .

Permanganates and sulfuric acid and benzene - Explosions can occur when permanganates that have been treated with sulfuric acid come into contact with benzene, carbon disulfide, diethyl ether, ethyl alcohol, petroleum, or organic matter.

Silver nitrate and ammonium hydroxide - When a mixture of 2896 ammonium hydroxide and silver nitrate was treated with a small amount of sodium hydroxide, black material precipitated. On being stirred the mixture exploded. The cause was formation of the sensitive silver nitride.

Silver nitrate and charcoal - A mixture of charcoal and silver nitrate ignites under impact.

Silver nitrate and ethyl alcohol - Alcohols should not be mixed with silver nitrate; an explosive fulminate may be formed.

Sodium hydroxide and trichloroethylene - When heated, trichloroethylene and sodium hydroxide or potassium hydroxide form explosive mixtures of dichloroacetylene. The presence of alkylamines, as a stabilizer in commercial trichloroethylene, furnishes a catalyst that accelerates this reaction. A pail of trichloroethylene dumped into a tank of caustic caused a fireball and eruption of the contents.

Sodium hydroxide and water - Sodium hydroxide in contact with water may generate enough heat to ignite adjacent combustible materials.

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Sodium hypochlorite and oxalic acid - Weighed quantities of the two chemicals were placed in a stainless steel beaker in preparation of a bleach solution. Just as water was first added, the mixture exploded. Sodium hypochlorite, a strong oxidizing agent, can react almost spontaneously with readily oxidizable materials, such as oxalic acid and cellulose.

Sodium nitrite and ammonium salts - A violent explosion occurs if an ammonium salt is melted with a nitrite salt.

Sodium nitrite, and cellulose - Sodium nitrite at 460°F in contact with the fiber drums in which it is shipped undergoes a vigorous decomposition reaction producing a propellant-type burning until the carton is consumed.

Sodium nitrite and sodium thiosulfate - When a sodium nitrite and thiosulfate mixture was heated to evaporate to dryness, a violent explosive occurred.

Zinc and acids - Zinc powder or dust in contact with acids evolves hydrogen. The heat of solution is sufficient that the hydrogen may ignite.

Zinc and ammonium nitrate - The two substances were mixed intimately and melted with 3 or 4 drops of water. After a short time, a violent reaction occurred with evolution of steam and zinc oxide.

Zinc and chlorates - A mixture of powdered zinc and an oxidizing agent such as potassium chlorate can be exploded by percussion.

Zinc and hydrazine mononitrate - When hydrazine mononitrate is heated in contact with zinc, copper, and most other metals, as well as oxides, sulfides, nitrides, and carbides, a flaming decomposition occurs at temperatures a little above its melting point.

Zinc and nitric acid - When concentrated nitric acid is poured on molten zinc, the reaction proceeds with incandescence.

Zinc and water - Zinc powder or dust in contact with water or damp air evolves hydrogen. The heat of reaction is such that the hydrogen may ignite.

Zirconium and alkali hydroxides - When a mixture of alkali hydroxide and zirconium is heated, the liberated oxygen reacts explosively with the zirconium.

Zirconium and alkali metal salts - Chromates dichromates, sulfates, molybdates, and tungstates of lithium, sodium, potassium, rubidium, and cesium will react violently, even explosively, with an excess of zirconium powder and yield the impure metal.

Zirconium and borax - A mixture of hydrated borax and zirconium explodes when heated.

Zirconium and carbon tetrachloride - An explosion occurred when zirconium sponge was placed in a beaker of carbon tetrachloride.

Zirconium and cupric oxide - Zirconium explodes violently with cupric oxide or lead oxide.

Zirconium and potassium nitrate - A mixture of powdered zirconium and potassium nitrate explodes when heated above the melting temperature.

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Zirconium-uranium alloy and nitric acid - Contact of etched or cleaned zirconium-uranium alloy with nitric acid results in a mild explosion.

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Incompatible Chemicals

The purpose of this section is to point out that in uncontrolled circumstances a violent reaction, fire, and/or explosion can occur with the combination of chemicals listed. They should be stored in such a manner that accidental contact is avoided.

Alkali and alkaline earth metals such Carbon dioxide, carbon tetrachloride and other chlorinated as sodium, potassium, cesium, hydrocarbons (prohibit water, foam, and dry chemical on lithium, magnesium, calcium, fires involving these metals). aluminum

Acetic acid Chromic acid, nitric acid, hydroxyl-containing compounds, ethylene glycol, perchloric acid, peroxides, and permagnanates.

Acetone Concentrated nitric and sulfuric acid mixtures.

Acetylene Chlorine, bromine, copper, silver, fluorine, and mercury.

Ammonia (anhydrous) Mercury, chlorine, calcium hypochlorite, iodine, bromine,

and hydrogen fluoride.

Ammonium nitrate Acids, metal powders, flammable liquids, chlorates,

nitrites, sulfur, finely divided organics or combustibles.

Aniline Nitric acid, hydrogen peroxide.

Bromine Ammonia, acetylene, butadiene, butane and other petroleum gases, hydrogen, sodium carbide, turpentine, benzene, and finely divided metals.

Calcium carbide Water (see also acetylene).

Carbon, activated Calcium hypochlorite.

Copper Acetylene, hydrogen peroxide.

Chlorates Ammonium salts, acids, metal powders, sulfur, finely

divided organics or combustibles.

Chromic acid Acetic acid, naphthalene, camphor, glycerin, turpentine, alcohol, and other flammable liquids.

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Chlorine Ammonia, acetylene, butadiene, butane and other petroleum gases, hydrogen, sodium carbide, turpentine, benzene, and finely divided metals.

Chlorine dioxide Ammonia, methane, phosphine, and hydrogen sulfide.

Cumene hydroperoxide Acids (organic or mineral).

Hydrocyanic acid Nitric acid, alkalis.

Hydrogen peroxide Copper, chromium, iron, most metals or their salts, any flammable liquid, combustible materials, aniline, nitro methane.

Hydrofluoric acid, anhyd. (hydrogen Ammonia, aqueous or anhydrous.

fluoride)

Hydrogen sulfide Fuming nitric acid, oxidizing gases.

Hydrocarbons (benzene, butane, Fluorine, chlorine, bromine, chromic acid, sodium

propane, gasoline, turpentine, etc.) peroxide.

Iodine Acetylene, ammonia (anhyd. or aqueous), hydrogen.

Mercury Acetylene, fulminic acid, ammonia.

Nitric acid (cone.) Acetic acid, aniline, chromic acid, hydrocyanic acid, hydrogen sulfide, flammable liquids, flammable gases, and nitratable substances.

Oxygen Oils, grease, hydrogen, flammable liquids, solids, or

gases.

Oxalic acid Silver, mercury.

Perchloric acid Acetic anhydride, bismuth and its alloys, alcohol, paper,

wood.

Phosphorus (white) Air, oxygen.

Potassium chlorate Acids (see also chlorate).

Potassium perchlorate Acids (see also perchlorates).

Potassium permanganate Glycerin, ethylene glycol, benzaldehyde, sulfuric acid.

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15

Silver Acetylene, oxalic acid, tartaric acid, fulminic acid, ammonium compounds Sodium See alkali metals

Sodium nitrite Ammonium nitrate and other ammonium salts

Sodium peroxide Any oxidizable substance, such as ehtanol, methanol, glacial acetic acid, acetic anhydride, benzaldehyde, carbon disulfide, glycerin, ethylene glycol, ehtyl acetate, methyl acetate, and furfural

Sulfuric acid Chlorates, perchlorates, permanganates

Zirconium Prohibit water, carbon tetrachloride, foam, and dry chemical on zirconium fires

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ATTACHMENT 4

METHOD FOR DETERMINING SUBSTITUTE REPORTABLE QUANTITIES

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3

If an RQ is not available for a known toxic material (e.g., a material for which the NIOSH Pocket Guide to Chemical Hazards lists an IDLH), the analyst may choose to either proceed with the consequence-based evaluation or determine a substitute RQ. To promote consistency and efficiency, System Safety Engineering will be the central point for generation and maintenance of substitute RQ values for those chemicals not listed in 40 CFR 302, Table 302.4.

EPA�s methods and criteria for establishing RQs listed in 40 CFR 302 are used to determine substitute RQ values for substances not listed in 40 CFR 302, with minor modifications. The method involves separate consideration of (1) toxicity by ingestion, contact, or inhalation; (2) ignitability; and (3) reactivity. EPA also considered aquatic toxicity and effects of repeated exposures, which are beyond the scope of hazard identification and facility classification for facility safety analysis. Application of EPA�s method and criteria requires data about physical and chemical properties of hazardous chemicals as described below. It may be convenient to list property data in a form shown in Figure 1. Figure 1 can be used for three different chemicals, which would be identified by listing across the top row. When values of the properties in Figure 1 are known, there can be a comprehensive basis for the degree of hazard for a material.

Mammalian Toxicity by Ingestion RQ

LD50 < 0.1 mg/kg 1 pound 0.1 mg/kg < LD50 < 1.0 mg/kg 10 1.0 mg/kg < LD50 < 10 mg/kg 100 10 mg/kg < LD50 < 100 mg/kg 1000 100 mg/kg < LD50 < 500 mg/kg 5000 Mammalian Toxicity by Ingestion RQ

LD50 < 0.04 mg/kg 1 pound 0.04 mg/kg < LD50 < 0.4 mg/kg 10 0.4 mg/kg < LD50 < 4 mg/kg 100 4 mg/kg < LD50 < 40 mg/kg 1000 40 mg/kg < LD50 < 200 mg/kg 5000

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4

Figure 1. Form to Record Data for Determining Substitute RQs

Chemical

State at 68°F

Molecular Weight

Synonyms:

CASRN:

NFPA H, F, R

Carcingoen?

Specific Gravity

Vapor Pressure, mm Hg

Boiling Point, °F

Flash Point, °F

LEL, %

UEL, %

Pyrophoric?

IDLH, ppm

ERPG-3, ppm

LD50, mg/kg, ingestion

LD50, mg/kg, dermal

LC50, ppm

LCLO, ppm

∆HR, kcal/gram

Comments Substitute RQs

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5

Mammilian Toxicity by Inhalation RQ

LC50 < 0.4 ppm 1 pound 0.4 ppm < LC50 < 4.0 ppm 10 4.0 ppm < LC50 < 40 ppm 100 40 ppm < LC50 < 400 ppm 1000 400 ppm < LC50 < 2000 ppm 5000 Values of LDP and LCw may be found in �Dangerous Properties of Industrial Materials�, by N.I. Sax and R.7. Lewis. These refer to amounts of chemicals that produce 50% mortality results in animal tests. When evaluating toxicity by ingestion, use LD50 test results from ref. 10 for chemicals administered orally or into body muscles or cavities by injection. When evaluating toxicity by contact, use LD50 from tests that administered chemicals directly onto the skin or subcutaneously (under the skin). LC50 vlaues apply to inhalation exposures. Ignitability RQ No 1-pound RQs on the basis of ignitability Pyrophoric or self ignitable 10 pounds FP < 100°F, BP < 100°F 100 FP < 100°F, BP> 100°F 1000 100°F < FP < 140°F 5000 Values of FP (flash point) and BP (boiling point) may be found in chemical and physical handbooks and manuals, or in Material Safety Data Sheets.

Reactivity

EPA�s methodology for establishing RQs .(in 40 CFR 302) for reactive substances is subjective and difficult to apply. The following simplified criteria should be used to determine substitute RQ values for reactivity. NFPA hazard ratings may be found in Material Safety Data Sheets provided by Energy Systems and in NFPA Standard 49.

NFPA Reactivity Level RQ 4 1 pound 3 10 2 100 1 5000 0 not applicable Carcinogenicity

It is assumed that EPA has established RQs for carcinogenetic substances and they are all listed in 40 CFR 302. It is not recommended to attempt to identify unlisted carcinogens.

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APPENDIX B

TABLES FOR HAZARD ANALYSIS

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B-3

Table B-1 Example Hazard Identification Table

(Facility Name) Hazard Identification Table � Hazard Energy Sources and Materials

Item Hazard Energy Source

or Material Exists (Y/N) Description Disposition

1.0 Electrical 1.1 Battery banks 1.2 Cable runs 1.3 Diesel generators 1.4 Electrical equipment 1.5 Heaters 1.6 High voltage (> 600V) 1.7 Locomotive, electrical 1.8 Motors 1.9 Power tools 1.10 Pumps 1.11 Service outlets, fittings 1.12 Switchgear 1.13 Transformers 1.14 Transmission lines 1.15 Wiring / underground wiring 1.16 Other 2.0 Thermal 2.1 Boilers 2.2 Bunsen burner / hot plates 2.3 Electrical equipment 2.4 Electrical wiring 2.5 Engine exhaust 2.6 Furnaces 2.7 Heaters 2.8 Lasers 2.9 Steam lines 2.10 Welding surfaces 2.11 Welding torch 2.12 Other 3.0 Pyrophoric Material 3.1 Pu and U metal 3.2 Other 4.0 Spontaneous Combustion 4.1 Cleaning / decon solvents 4.2 Fuels (gasoline, diesel fuel, etc.) 4.3 Grease 4.4 Nitric acid and organics 4.5 Paint solvents 4.6 Other

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B-4

Table B-1 Example Hazard Identification Table (Continued)

(Facility Name) Hazard Identification Table � Hazard Energy Sources and Materials

Item Hazard Energy Source

or Material Exists (Y/N) Description Disposition

5.0 Open Flame 5.1 Bunsen burners 5.2 Welding / cutting torches 5.3 Other 6.0 Flammables 6.1 Cleaning / decon solvents 6.2 Flammable gases 6.3 Flammable liquids 6.4 Gasoline 6.5 Natural Gas 6.6 Paint / paint solvent 6.7 Propane 6.8 Spray paint 6.9 Other 7.0 Combustibles 7.1 Paper / wood products 7.2 Petroleum based products 7.3 Plastics 7.4 Other 8.0 Chemical Reactions 8.1 Concentration 8.2 Disassociation 8.3 Exothermic 8.4 Incompatible chemical mixing 8.5 Uncontrolled chemical reactions 9.0 Explosive Material 9.1 Caps 9.2 Dusts 9.3 Dynamite 9.4 Electric squibs 9.5 Explosive chemicals 9.6 Explosive gases 9.7 Hydrogen 9.8 Hydrogen (batteries) 9.9 Nitrates 9.10 Peroxides 9.11 Primer cord 9.12 Propane 9.13 Other

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B-5

Table B-1 Example Hazard Identification Table (Continued)

(Facility Name) Hazard Identification Table � Hazard Energy Sources and Materials

Item Hazard Energy Source

or Material Exists (Y/N) Description Disposition

10.0 Kinetic (Linear and Rotational) 10.1 Acceleration / deceleration 10.2 Bearings 10.3 Belts 10.4 Carts / dollies 10.5 Centrifuges 10.6 Crane loads (in motion) 10.7 Drills 10.8 Fans 10.9 Firearm discharge 10.10 Fork lifts 10.11 Gears 10.12 Grinders 10.13 Motors 10.14 Power tools 10.15 Presses / shears 10.16 Rail cars 10.17 Saws 10.18 Vehicles 10.19 Vibration 10.20 Other 11.0 Potential (Pressure) 11.1 Autoclaves 11.2 Boilers 11.3 Coiled springs 11.4 Furnaces 11.5 Gas bottles 11.6 Gas receivers 11.7 Pressure vessels 11.8 Pressurized system (e.g., air) 11.9 Steam headers and lines 11.10 Stressed members 11.11 Other

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B-6

Table B-1 Example Hazard Identification Table (Continued)

(Facility Name) Hazard Identification Table � Hazard Energy Sources and Materials

Item Hazard Energy Source

or Material Exists (Y/N) Description Disposition

12.0 Potential (Height / Mass) 12.1 Cranes / hoists 12.2 Elevated doors 12.3 Elevated work surfaces 12.4 Elevators 12.5 Lifts 12.6 Loading docks 12.7 Mezzanines 12.8 Floor pits 12.9 Scaffolds and ladders 12.10 Stacked material 12.11 Stairs 12.12 Other 13.0 Internal Flooding Sources 13.1 Domestic water 13.2 Fire suppression piping 13.3 Process water 13.4 Other 14.0 Physical 14.1 Sharp edges or points 14.2 Pinch points 14.3 Confined space 14.4 Tripping 15.0 Radiological Material 15.1 Radiological material 16.0 Hazardous Material 16.1 Asphyxiants 16.2 Bacteria / viruses 16.3 Beryllium and compounds 16.4 Biologicals 16.5 Carcinogens 16.6 Chlorine and compounds 16.7 Corrosives 16.8 Decontamination solutions 16.9 Dusts and particles 16.10 Fluorides 16.11 Hydrides 16.12 Lead 16.13 Oxidizers 16.14 Poisons (herbicides, insecticides)

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B-7

Table B-1 Example Hazard Identification Table (Continued)

(Facility Name) Hazard Identification Table � Hazard Energy Sources and Materials

Item Hazard Energy Source

or Material Exists (Y/N) Description Disposition

16.15 Other 17.0 Ionizing Radiation Sources 17.1 Contamination 17.2 Electron beams 17.3 Radioactive material 17.4 Radioactive sources 17.5 Radiography equipment 17.6 X-ray machines 17.7 Other 18.0 Non-Ionizing Radiation 18.1 Lasers 18.2 Other 19.0 Criticality 19.1 Fissile material 20.0 Non-facility Events 20.1 Aircraft crash 20.2 Explosion 20.3 Fire 20.4 Power outage 20.5 Transportation accident 20.6 Other 21.0 Vehicles in Motion 21.1 Airplane 21.2 Crane / hoist 21.3 Forklifts 21.4 Heavy construction equipment 21.5 Helicopter 21.6 Train 21.7 Truck / car 22.0 Natural Phenomena 22.1 Earthquake 22.2 Flood 22.3 Lightning 22.4 Rain / hail 22.5 Snow / freezing weather 22.6 Straight wind 22.7 Tornado

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Table B-2 Hazard Sources and Potential Event Types

Hazard Energy Source or Material Group Potential Events by Category

Electrical E-1: Fire � In combination with combustible/flammable material E-2: Explosion � In combination with explosive material E-4: Direct Exposure � Worker injury

Thermal E-1: Fire � In combination with combustible/flammable material E-2: Explosion � In combination with explosive material E-4: Direct Exposure � Worker injury E-5: Criticality � Increased concentration

Pyrophoric Material E-1: Fire � Pyrophoric; may serve as ignition source for larger fires E-2: Explosion � In combination with explosive material

Spontaneous Combustion E-1: Fire � May serve as ignition source for larger fires E-2: Explosion � In combination with explosive material

Open Flame E-1: Fire � In combination with combustible/flammable material E-2: Explosion � In combination with explosive material

Flammables E-1: Fire � In combination with ignition source Combustibles E-1: Fire � In combination with ignition source Explosive Material E-2: Explosion � In combination with ignition source

E-3: Loss of confinement � Missiles ( in combination with ignition source) E-5: Criticality � Loss of configuration or spacing

Chemical Reactions E-1: Fire � Fire or other thermal effect E-2: Explosion � Explosion or over-pressurization E-3: Loss of confinement � Toxic gas generation E-5: Criticality � Increased concentration, precipitation of material

Kinetic (Linear and Rotational)

E-3: Loss of confinement � Impacts, acceleration/deceleration, missiles E-4: Direct Exposure � Worker injury E-5: Criticality � Loss of configuration or spacing

Potential (Pressure) E-3: Loss of confinement � Impacts, missiles E-4: Direct Exposure � Worker injury E-5: Criticality � Loss of configuration or spacing

Potential (Height / Mass) E-3: Loss of confinement � Impacts (falling objects), dropping E-4: Direct Exposure � Worker injury E-5: Criticality � Loss of configuration or spacing

Internal Flooding Sources E-3: Loss of confinement � Ground/surface water runoff E-5: Criticality � Increased moderation

Physical E-3: Loss of confinement � Puncture, dropping E-4: Direct Exposure � Worker injury

Radiological Material All Events � Potentially releasable material Hazardous Material All Events � Potentially releasable material Biological Material All Events � Potentially releasable material Ionizing Radiation Sources E-4: Direct Exposure � Direct exposure to worker Non-Ionizing Radiation E-1: Fire � Thermal effects in combination with combustible/flammable material

E-2: Explosion � Thermal effects in combination with explosive material E-4: Direct Exposure � Worker injury Other � may interfere with equipment operation

Criticality E-5: Criticality � Criticality Non-facility Events May lead to any event category (E-1 through E-5) Vehicles in Motion May lead to any event category (E-1 through E-5) Natural Phenomena May lead to any event category (E-1 through E-5)

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B-9

Table B-3 Frequency Evaluation Levels

Frequency Level Acronym Frequency Qualitative Description

Anticipated A f ≥ 10-2 /yr Events that might occur several times during the lifetime of the facility

Unlikely U 10-4 ≤ f < 10-2 /yr Events not anticipated during the lifetime of the facility

Extremely Unlikely EU 10-6 ≤ f < 10-4 /yr Events that will probably not occur during the lifetime of the facility

Beyond Extremely Unlikely BEU f < 10-6 /yr All other Events

Table B-4 Radiological Consequence Evaluation Levels for Hazard Receptors

Consequence Level

(Abbreviation)

Offsite Public

Facility Worker

(Inside Facility)

Co-located Worker

(Outside Facility)

High

(H)

C ≥ 25.0 rem

prompt worker fatality, acute injury that is immediately life threatening or

permanently disabling

C ≥ 100.0 rem

Moderate

(M)

5.0 ≤ C < 25.0 rem

serious injury, no immediate loss of life, no permanent disabilities,

hospitalization required

25.0 ≤ C < 100.0 rem

Low

(L)

0.5 ≤ C < 5.0 rem

minor injuries, no hospitalization

5.0 ≤ C < 25.0 rem

Negligible

(N)

C < 0.5 rem

C < Low

C < 5.0 rem

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B-10

Table B-5 Chemical Consequence Evaluation Levels for Hazard Receptors

Consequence Level (Abbreviation)

Offsite Public Facility Worker (Inside Facility)

Co-located Worker (Outside Facility)

High

(H) C ≥ ERPG-2

prompt worker fatality, acute injury that is immediately life threatening or

permanently disabling C ≥ ERPG-3

Moderate

(M) ERPG-1 ≤ C < ERPG-2

serious injury, no immediate loss of life, no permanent disabilities,

hospitalization required ERPG-2 ≤ C < ERPG-3

Low

(L) PEL-TWA ≤ C < ERPG-1 minor injuries, no hospitalization ERPG-1 ≤ C < ERPG-2

Negligible

(N) C < PEL-TWA C < Low C < ERPG-1

Note: If Emergency Response Planning Guideline (ERPG) does not exist, then the Temporary Emergency Exposure Limit (TEEL) should be used. (TEEL-3 = ERPG-3, TEEL-2 = ERPG-2, TEEL-1 = ERPG-1). Also, the PEL-TWA value may be substituted with the TEEL-0 value if PEL-TWA information is not available or if the decision is made by the HA team to use the TEEL-0 value.

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B-11

Table B-6 Risk Binning Matrix–Facility Worker (inside facility)

Frequency →

Consequence

Beyond

Extremely Unlikely f < 10-6 /yr

Extremely Unlikely

10-6 ≤ f < 10-4 /yr

Unlikely

10-4 ≤ f < 10-2 /yr

Anticipated

f ≥ 10-2 /yr

High

Prompt worker fatality, acute injury that is immediately life threatening or permanently disabling

D A A A

Moderate

Serious injury, no immediate loss of life, no permanent disabilities, hospitalization required

D D C C

Low

Minor injuries, no hospitalization

D D D D

Negligible

C < Low

D D D D

Key:

A Region A

Unmitigated events with risk falling in or challenging Region A require further evaluation as specified in the Control Selection Document (CSD).

C Region C

Unmitigated events with risk falling in or challenging Region C may need additional consideration as specified in the CSD.

D Region D

Unmitigated events with risk falling in Region D generally have negligible risk and no further action is required.

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Table B-7 Risk Binning Matrix–Co-located Worker

Frequency →

Consequence

Beyond

Extremely Unlikely f < 10-6 /yr

Extremely Unlikely

10-6 ≤ f < 10-4 /yr

Unlikely

10-4 ≤ f < 10-2 /yr

Anticipated

f ≥ 10-2 /yr

High

Radiological: C ≥ 100 rem Chemical: C ≥ ERPG-3

D A A A

Moderate

Radiological: 25 ≤ C < 100 rem Chemical: ERPG-2 ≤ C < ERPG-3

D D C C

Low Radiological: 5 ≤ C < 25 rem Chemical: ERPG-1 ≤ C < ERPG-2

D D D D

Negligible Radiological: C < 5 rem Chemical: C < ERPG-1

D D D D

Key:

A Region A

Unmitigated events with risk falling in or challenging Region A require further evaluation as specified in the Control Selection Document (CSD).

C Region C

Unmitigated events with risk falling in or challenging Region C may need additional consideration as specified in the CSD.

D Region D

Unmitigated events with risk falling in Region D generally have negligible risk and no further action is required.

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Table B-8 Risk Binning Matrix–Offsite Public

Frequency →

Consequence

Beyond

Extremely Unlikely f < 10-6 /yr

Extremely Unlikely

10-6 ≤ f < 10-4 /yr

Unlikely

10-4 ≤ f < 10-2 /yr

Anticipated

f ≥ 10-2 /yr

High

Radiological: C ≥ 25 rem Chemical: C ≥ ERPG-2

A1 A A A

Moderate

Radiological: 5 ≤ C < 25 rem Chemical: ERPG-1 ≤ C < ERPG-2

D C B B

Low

Radiological: 0.5 ≤ C < 5 rem Chemical: PEL-TWA ≤ C < ERPG-1

D C C B

Negligible

Radiological: C < 0.5 rem Chemical: C < PEL-TWA

D D D D

Key:

A Region A

Unmitigated events with risk falling in or challenging Region A require further evaluation as specified in the Control Selection Document (CSD).

A1 Region A1

Unmitigated events with risk falling in or challenging Region A1 due to radiological release require further evaluation as specified in the CSD, if the event is an operational accident (i.e. internally initiated).

B Region B

Unmitigated events with risk falling in or challenging Region B due to radiological release require further

evaluation as specified in the CSD. Unmitigated events with risk falling in or challenging Region B due to chemical release may need additional consideration as specified in the CSD.

C Region C

Unmitigated events with risk falling in or challenging Region B may need additional consideration as specified in the CSD.

D Region D

Unmitigated events with risk falling in Region D generally have negligible risk and no further action is required.

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Table B-9 Example of Completed Hazard Evaluation Table

Table Number: Hazard Evaluation Table for (Facility Area) Unmitigated Mitigated

Event No.

Event Cat. Event Description Causes

Freq. Level

Consequence Level

Risk Rank

Method of

Detection Preventive Features Mitigative Features Freq. Level

Consequence Level

Risk Rank

BC-1 E-1 Large fire Location: Backpulse Chamber Areas Release Mechanism: Thermal (fire) Hazard Source: Combustion products; toxic smoke or gases

Combustible/ flammable material: • Miscellaneous

combustibles • Hydrogen from

Uninterrupted Power Source battery

AND Ignition sources • Electrical short • Thermal energy

from electrical equipment, friction from belts, bearings, etc.

A 1,2

Chemical FW: High Co-located: Mod. Offsite: Low Physical High facility worker consequences due to physical nature of event Other Impacts: Combustion products may plug High Efficiency Particulate Air filter causing loss of filtration

C A C B P A

Design: Electrical equipment design code; NFPA standards. Administrative: Combustible material control; Trained personnel; Standard Operating Procedures

Design: Fire detection and suppression system; Building design; Building ventilation system. Administrative: Fire Department response, Emergency Operating Procedures, Trained personnel.

A Chemical FW: Mod. Co-located: Low Offsite: Neg. Physical Low. Workers are trained to recognize obvious hazards and evacuate

C C D D P D

BC-2 E-2 Flammable gas detonation Location: Backpulse Chamber Areas Release Mechanism: Explosion Hazard Source: Filtrate solution (100 gal)

Explosive material: • Oxygen diffuses

into vapor space and mixes with flammable gas (e.g., benzene)

AND Ignition sources • Electrical short • Thermal energy

from electrical equipment, friction from belts, bearings, etc.

U 1 IC3 IC4

Radiological FW: Low Co-located: Neg. Offsite: Neg. Chemical FW: Moderate Co-Located: Neg. Offsite: Neg. Physical High Worker consequences due to physical nature of event

R D D D C C D D P A

Design: Backpulse chamber design; nitrogen supply (positive pressure on backpulse chamber); backup nitrogen system Administrative: Limited ignition sources in room

Design: Building design; fire detection and suppression system; Building ventilation system. Administrative: Personnel Access Restrictions; Emergency Operating Procedures; Trained personnel.

EU

Radiological FW: Low Co-located: Neg. Offsite: Neg. Chemical FW: Moderate Co-located: Neg. Offsite: Neg. Physical Negligible. Access Restrictions will protect worker from serious injury

R D D D C D D D P D

1. Engineering judgement; 2. Equipment failure rate database (Ref. XX); 3. ICs are identified in the document text

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APPENDIX C

HAZARDS SCREENING CRITERIA

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Table C-1 Standard Industrial Hazard Screening Criteria

Hazard Criteria/Measure Guidance

Chemical Hazards

This appendix Reportable Quantity (RQ), Threshold Quantity (TQ), Threshold Planning Quantity (TPQ) screening values as discussed in this appendix

Toxic Material

This appendix RQ, TQ, TPQ screening values as discussed in this appendix

X-Ray Equipment

Does not meet American National Standard Institute (ANSI) X-Ray standards

Applicable national codes and standards (e.g., American Nuclear Society (ANS) N537/NBS123)

Flammable Materials

N/A Considered as a contributor/initiator for fire events.

Reactive Material

N/A Screened according to RQ, TQ, TPQ screening values or SARA #00-26

Chemical Compatibility

N/A Screened according to RQ, TQ, TPQ screening values or SARA #00-26

Lasers

Class III non-enclosed beam Class IV

ANSI Z136.1 �Safe Use of Lasers classifies lasers in Classes I through IV�

Electrical

>600 volts or >600 volts and >24 milli-Ampere or >50j stored energy at 600 volts

National Electric Code identifies these as systems requiring special considerations

Kinetic Energy

�Unique or Unusual� high kinetic energy sources (e.g., high energy flywheels, large centrifuges)

Many high kinetic energy systems are capable of causing personnel injury. Most of these (e.g., cars, trucks, forklifts, cranes) are standard industrial hazards unless an initiator for another significant event. Unique systems (e.g., high energy flywheels, large centrifuges) are not considered standard industrial hazards.

Pressure

Stored energy >0.1 LB TNT Pressure > 3000 psig

High hydraulic pressures and pressurized gas bottles are standard industrial hazards. Large volumes of compressed gases are not routine.

Temperature

Temperatures which could act as an initiator

High temperature systems are standard industrial hazards but an evaluation is required if the temperature could result in an overpressure, creation of toxic products or cause a fire.

Biohazards

As identified by HP or Industrial Hygiene

Asphyxiants

Oxygen content less than 18% Asphyxiants do not have Threshold Limit Value (TLV) and cannot be handled as toxic material. Consider areas that could entrap asphyxiants and areas storing cylinders of asphyxiants

• CHEMICAL SCREENING CRITERIA

The lists of chemicals considered to be hazardous are given in 40 CFR 302, 40 CFR 355, 29 CFR 1910.119, and 40 CFR 68.130 (Ref. 1, 2, 3, 4).

A chemical is screened if any of the following conditions apply:

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C-4

− The chemical is on the referenced lists but are less than the RQs (40 CFR 302, 40 CFR 355) (Ref. 1, 2).

− The chemical is not on the referenced lists but satisfy one of the following conditions:

− Is less than 1 pound of solids or liquids

− Is less than 100 pounds of solids or liquids, or 10 pounds of gasses, with National Fire Protection Association (NFPA) Health Hazard ratings of 1 or 2 or TEEL-2 greater than 100

− Is in common use by office workers, the public, or others

• X-RAY EQUIPMENT AND ACCELERATORS

The intent is to screen out those facilities with X-ray equipment or simple accelerators that are commercially available, conform to appropriate national codes and standards (e.g., ANS N537/NBS123 for X-ray equipment or ANS 43.1 for accelerators), and have not been modified with regard to safety-related design and operating features, such as voltage and shielding. If the X-ray system does not conform to the appropriate national code standard, or the accelerator is considered �complex,� then it must be identified for further HAs. (See Section 2.6.2.3.2 of ANS 43.1, Complex Accelerators, for the definition of simple and complex accelerators.)

• LASERS

The intent is to screen out Class I and Class II lasers (per ANSI Z136.1) and Class III lasers with enclosed beams, since these do not represent a significant health threat. If these Class I, II, and III laser systems do not conform to the appropriate national standard, then they must be identified for further HAs. Class III lasers with non-enclosed beams and Class IV lasers are to be identified for further analysis. Gas supplies that are an integral part of an unmodified, sealed purchased system design do not have to be treated separately; however, gas supplies that are not sealed in the purchased system or systems that have been modified must be considered separately, as appropriate (i.e., toxic material criteria).

• ELECTRICAL

The intent is to screen out standard electrical hazards, but to retain for further analysis those that represent special safety concerns. Systems to be retained are (1) those with 600 volts or more and 25 milli-Ampere or more output, and (2) stored energy systems with 50J or more stored energy and terminal-to-terminal voltage of 600 volts or more. The National Electric Code (NEC) 70-1990 identifies these as systems requiring special consideration.

• TEMPERATURE

The intent is to screen out high temperature systems whose only consequence is a contact burn and to keep systems that could result in a strong overpressure if a coolant or other fluid contacted the high temperature mass, that could cause toxic products if materials in the area were exposed to the high temperature, or that could cause a fire that would spread radioactive or toxic materials.

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C-5

• BIOHAZARDS

The intent is to screen out common sources of biohazards, such as cooling towers, but to retain for further, analysis facilities containing biohazards of such a nature that special industrial hygiene controls (protective clothing, breathing apparatus, special warning placards) are required.

• ASPHYXIANT

Asphyxiants do not have TLVs and, therefore, cannot be handled as toxic materials. Consider if there are areas to entrap asphyxiants and unsuspecting personnel or situations that would impact large numbers of people. Cylinders of compressed asphyxiants should be included in these evaluations. Such situations should be identified for further analysis. Specifically, those situations in which the oxygen level would be less than 18%, due to increased asphyxiant gas concentration, should be kept for further analysis.

• ADDITIONAL GUIDANCE

Hazardous materials or operations encountered in general industry, in appropriate applications, that are adequately controlled by OSHA regulations or one or more national consensus standards (e.g., American Society of Mechanical Engineers, ANSI, NFPA, Institute of Electrical and Electronics Engineers, NEC), where these standards are adequate to define special safety requirements are considered to be SIHs. SIHs must be considered as initiators for accidents involving hazards that are not SIHs. For example, flammable materials may be screened out as a SIH, however, if the flammable materials could potentially cause a fire that releases toxic or radioactive materials, the flammable materials must be considered as a potential initiator for the release.

REFERENCES

1. �Protection of the Environment,� Title 40 Code of Federal Regulations, Part 302.4, Designation, Reportable Quantities, and Notification. U.S. Environmental Protection Agency, Washington, DC July 1992.

2. �Protection of the Environment,� Title 40 Code of Federal Regulations, Part 355, Emergency Planning and Notification. U.S. Environmental Protection Agency, Washington, DC, July 1992.

3. �Labor,� Title 29 Code of Federal Regulations, Part 1910.119(e)(6), Process Safety Management Of Highly Hazardous Chemicals. U.S. Department of Labor, Washington, DC, May 26, 1992.

4. �Protection of the Environment,� Title 40 Code of Federal Regulations, Part 68, Accidental Release Prevention Requirements: Risk Management Programs Under Clean Air Act. U.S. Environmental Protection Agency, Washington, DC, March 1995.

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APPENDIX D

INTEGRATED WORK PROCESS

Page 118: Hazard Categorization
Page 119: Hazard Categorization

D-3

Figure D-1. Integrated Safety Basis Documents Process Flowchart

Facility/Operation

Description (1)

Hazardous Material Inventory

(Bounding) (1)

Initial HazardCategorization/ Classification

(2)

<Cat 3 and Low?

Yes Unmitigated Hazard Analysis

(2)

No

Qty > RAD limit? (2)

Other Industrial Facility (7)

No

<Cat 3 ?

Documented UHA & FHC(HAD) (2)

Yes

BJC NS approval?

DOEapproval?

Yes

UHA & FHC to ASA(7)

Yes

Accident Scenario &

Seq. (5)No

No

No

Source Term Analysis (5)

Mitigated Hazard Analysis

(2)-----------

Consequence & Freq. Analysis Workers

(2)

Consistency Review (5)

Final SelectionSC/SS/DID

SSCs & ACs (6)

Challenges EGs (5)

TSR(8)

EMHS(3)

<Order 151 Limit

Done

Yes

Fire Hazards Analysis

(4)

Criticality Analysis

EMHA(3)

Yes

List of Chem Haz & SMPs

(7)

BJC NS approval?

No

Rad Facility(7)

EM

FP

DSA(8)

No

FHA(4)

EM

FP

Yes

EM Accident Scenario &

Seq.(3)

Significant New Fac. or Unique FH?

(4)No

Yes FHA Conclusions

(4)

Rad Facility

HASP(7)

Initial Controls Selection

(6)

Transmit to DOE

Consequence Analysis & Frequency

Analysis Public(5)

No

<Cat 2?No

HAD(2)

Yes

BJC NS approval?

DOEapproval?

Yes

Yes(Cat 3)

No (Cat 2)

Yes

1- Facility Description Guide2- Hazard Analysis Guide3- Emergency Management Guide4- Fire Hazard Guide5- Accident Analysis Guide6- Control Selection Guide7- Simplified Documented Safety Analysis Guide8- Documented Safety Analysis Guide

No (Cat 2)

Page 120: Hazard Categorization

D-4

Figure D-2. Initial Hazard Categorization/Classification Process Flowchart

Final Determination

Non-Radiological Categorization

IdentifyFacility

SegmentFacility

DetermineHazardous

MaterialInventory

RadiologicalInventory?

Yes

Is NuclideFissionable?

Is InventoryAbove

40CFR302.4RQ?

Are CriticalMass LimitsExceeded?

Is InventoryAbove Cat 3Quantities?

Is InventoryAbove Cat 2Quantities?

Is FacilityClass A

Reactor orDesignated

Cat 1?

NoNo

YesYes

Yes

Yes

Yes

OtherIndustrial

RadiologicalFacility

Category 3

Category 2

Category 1

No

No

No

No

Yes

ChemicalInventory?

No FurtherEval. Req’d

No

Yes

No

Determine Onsite andOffsite Consequences

AreConsequences

Irreversible?

AreConsequences

Off-site?

AreConsequencesin Immediate

Area of Event?

AreConsequences

Reversible?

AreConsequences

Off-site?

DoConsequencesEffect a Large

Number ofPeople?

DoConsequencesEffect a Large

Number ofPeople?

OtherIndustrial

LowHazard

ModerateHazard

Is FacilityDesignated asHigh Hazard?

HighHazard

Yes

No

YesYes

Yes

Yes Yes

Yes

Yes

No

No

No

No

No

No

No

Preliminary Activities

Radiological Categorization

LEGEND

Above RQ?

Yes

No

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D-5

Figure D-3. Hazard Analysis Process Flowchart

Assemble HATeam

Select Method

Develop Work

Plan

Gather Inputs

HazardousMaterial

Inventory( Bounding)

SystemDesign

Description

FacilityDesign

Description

Drawingsand

Diagrams

HazardIdentification

Divide

AreasFacility into

WalkdownFacility

HazardSIH?

ScreenHazards

HazardousEvent

Development

FrequencyAnalysis

Consequence

Analysis

Identify PotentialPreventive and

ControlsMitigative

RiskChallenges

EGs?

Document

UnmitigatedHC and

HA

No FurtherEval. Req’d

Apply

ControlsSelected

DetermineMitigated

Frequency

Update HATo ShowMitigated

Risk

No

Yes

Yes

No

Hazard IDComplete

Table

No FurtherEval. Req’d

RiskBinning

ChallengesEGs?

Offsite Risk

AccidentAnalysis

Yes

No

AdditionalSelection ofSC/SS/DID

SSCs & ACs

DetermineMitigated

Consequence

RiskBinning

MitigatedHazard

Evaluation

Non-HA Activities

Preliminary Activities

Unmitigated Hazard Analysis

Mitigated Hazard Analysis

LEGEND

IdentifyInitial Conditions

RiskChallenges

EGs?

No

Yes

Initial HazardCategorization

< Cat 3 orLow?

HazardAssessmentDocument

Yes

No

FunctionalClassification

ControlSelection

Final Versionto FunctionalClassification

FunctionalClassification

Control Selection forInitial Conditions

UnmitigatedHazard

Evaluation