Risk Assessment ToolsSelecting, Modifying and Applying

Methods

UCM Risk Assessment Symposium November 5, 2015

Bruce Lyon, CSP, PE, ARM, CHMMHays Companies

Risk Assessment Tools

1. The Hazard Analysis and Risk Assessment Process2. Assessment Methods3. Selecting and Modifying Methods4. Applying Methods

Hazard Analysis and Risk Assessment

Analyze how event could occur and its

Likelihood (L)

Estimate Risk Level

S x L = R

Hazard Analysis Identify Hazards and Exposures

Anayze Range of Severities

Risk Assessment Identify Hazards and Exposures

Choose a Severity Consequence (S)

of Concern

Definitions

Risk Assessment • Overall process of risk identification, risk analysis and risk evaluation.

(ISO Guide 73/ANSI/ASSE Z690.1-2011)• A process that commences with hazard identification and analysis,

through which the probable severity of harm or damage is established, followed by an estimate of the probability of the incident or exposure occurring, and concluding with a statement of risk. (ANSI/ASSE Z590.3 PtD Standard)

Risk Assessment

The purpose: to determine whether the level of risk is acceptable, or whether more needs to be done to control or reduce the risk.The process should be carried out in a rational, logical and structured manner.

Risk Assessment within the Risk Management Framework

Establish Risk Criteria

Establish Context

Assemble Team

Identify Hazards

Analyze Risks

Evaluate Risks

Treat Risks

Document

Monitor / Review

Risk Assessment

Process

ISO 31010/ANSI Z690.3 Methods

1. Brainstorming2. Structure Interviews3. Delphi4. Checklists5. Preliminary Hazard Analysis6. Hazard and Operability Studies (HAZOP)7. Hazard Analysis and Critical Control Points (HACCP)8. Toxicity Assessment9. Structured What-if Analysis 10. Scenario Analysis11. Business Impact Analysis12. Root Cause Analysis13. Failure Modes and Effect Analysis14. Fault Tree Analysis15. Event Tree Analysis16. Cause and Consequence Analysis

17. Cause and Effect Analysis18. Layers of Protection Analysis19. Decision Tree Analysis20. Human Reliability Analysis21. Bow Tie Analysis22. Reliability Centered Maintenance23. Sneak Analysis24. Markov Analysis25. Monte Carlo Analysis26. Bayesian Statistics and Bayes Nets27. FN Curves28. Risk Indices29. Consequence/Probability Matrix30. Cost/Benefit Analysis31. Multi-Criteria Decision Analysis

Z590.3 PtD Methods

1. Design Safety Reviews2. Checklists3. Risk Assessment Matrix4. Preliminary Hazard Analysis5. What-if Analysis 6. What-if/Checklist Analysis7. Hazard and Operability

Studies (HAZOP)

8. Failure Modes and Effect Analysis

9. Fault Tree Analysis10.Management Oversight and

Risk Tree (MORT)

ANSI Z10 Methods

1. Design Reviews2. Brainstorming3. Checklists4. Consequence/Probability Matrix5. Risk Assessment Matrix

Selecting Risk Assessment Tools

Consider the following:• What is the Application (New Design; Existing System; General or

Specific Hazards)• What is the Level of Detail Needed • What is the Complexity of the System• What is the Size of the System• What Resources are Available

Selecting Risk Assessment Tools

As a general rule, when selecting a risk assessment method, the simplest tool or tools that provide sufficient information to make an appropriate risk management decision is advised.

No single assessment tool is able to meet all of the requirements for risk assessment, as all tools have limitations and weaknesses.

Modified tools may be necessary (and even desired)Often a combination of tools is necessary.

Selecting Risk Assessment Tools

Fundamental Tools commonly used include:• Checklists• Brainstorming• JHAs and JRAs• Preliminary Hazard Analysis • What-if Analysis• Failure Mode and Effects Analysis • Bow Tie Analysis• Risk Matrix

Checklist Tools

Used to identify common hazardsIndustry/process specific checklistsCan be customized for applicationEasy to use, but limited to existing listGenerally followed by other risk analysis and evaluation tools

Brainstorming

Used to identify potential hazards and scenariosCan be structured or unstructuredRequires a facilitator to lead session and record ideas Generally followed by other risk analysis and evaluation tools

Brainstorming

1. State Goal2. No Critical Remarks3. Generate Ideas4. Record Everything5. Evaluate and Qualify

Job Hazard Analysis (JHA)

Used to identify job steps, hazards and controls Helpful in job training and incident investigationDoes not include an ‘assessment of risk’, just identification of hazards

and controls

Job Hazard Analysis (JHA)

Job Risk Assessment (JRA)

Simple toolSame as JHA but includes a ‘risk assessment’ of each hazardAllow hazards and corrective measures to be prioritized by ‘risk level’

Job Risk Assessment (JRA)

Preliminary Hazard Analysis

An ‘Initial Analysis’ toolUsed to identify hazards and control measures for new designs or

existing systemsUsed when limited information is availableAllows for risk levels to be prioritized for further assessment and

management

Preliminary Hazard Analysis Example

Winery Risk Assessment100% Liquid Sulfur Dioxide (SO2) used for dosing large tanks inside buildings.

Preliminary Hazard Analysis Example

Risks of using 100% Sulfur Dioxide • Potential for releases in winery and bottling area• Lethal dose = 100 ppm (Cal-OSHA PEL = 2 ppm)• Can cause blindness • Environmental concerns (reporting requirements)• Transporting, dispensing, handling, storage concerns

Preliminary Hazard Analysis Example

Winery Risks

Sulfur dioxide gas is heavier than air and can accumulate in closed areas.

The configuration and lack of ventilation in the bottling area presented a significant risk to employees should a SO2 release occur in the area.

Risk CriteriaSeverity Level DefinitionCatastrophic (4) Fatalities; Damage to Community, Environment, and Reputation

High (3) Permanent Disability Injury or Illness; Multiple Injury Events

Moderate (2) Injury or Illness Requiring Medical Attention

Low (1) Minor Injury or First Aid Incident

Likelihood Level DefinitionVery Likely (4) Will happen under right situations; has occurred multiple timesLikely (3) Likely to happen under right circumstances; has occurred in pastPossible (2) Can happen in certain situationsUnlikely (1) Unlikely to happen; remotely possible

Low (1)

Moderate (2)

High (3)

Catastrophic (4)

Very Likely (4) 4 8 12 16Likely (3) 3 6 9 12

Possible (2) 2 4 6 8Unlikely (1) 1 2 3 4

Preliminary Hazard Analysis Example

Task Hazard

Curren

t Severit

y

Curren

t Likelihood

Curren

t Risk

Level

Recommended Controls

Future Severity

Future Likelihood

Future Risk

Level

SO2 Dosing using 100% SO2 liquid

Health risk from leak or release; 2 ppm PEL; 100 ppm lethal dose;Heavier than air. EPA regulated product. 4 3 12

Preliminary Hazard Analysis Example

Task Hazard

Curren

t Severit

y

Curren

t Likelihood

Curren

t Risk

Level

Recommended Controls

Future Severity

Future Likelihood

Future Risk

Level

SO2 Dosing using 100% SO2 liquid

Health risk from leak or release; 2 ppm PEL; 100 ppm lethal dose;Heavier than air. EPA regulated product. 4 3 12

Substitute 100% SO2 with 6% liquid SO2 and K2S2O5 (potassium

meta-bisulfite) effervescent tables, granular, powder 2 2 4

What-if Analysis

• A team-based, brainstorming process • Engineering, production, maintenance, fire protection, SH&E

• Used to identify and analyze scenarios and hazards • Typically does not include ‘risk analysis’ (severity and likelihood levels)• Can be modified to include risk analysis

What-if Analysis

What-if AnalysisABC – Repair Facility

Vapor Combustor Process Hazard What-if Analysis

Date: June 17 & 18, 2009 Team members: Bruce Lyon – Hays Companies; Deane Holmes – Hays Companies; Tim G – ABC Engineer; Gary F – Env.; John K – Safety; David B - Maintenance

Pre-Startup & Vapor Combustor Purging

ID # What if… Causes Effect Safeguards

A1. Insufficient purging of vapor combustor stack

Failure of assist air blower

Will not start A1.1 Operator training in JSA & purging procedureA1.2 Alarm if assist air blower fails

A2. Steam is used to purge the waste gas line

Steam used to purge system

Steam condenses in piping without displacing air Nitrogen purge line is hard piped in system (not possible to purge with steam)

A2.1 Nitrogen purge line is hard piped in system (not possible to purge with steam)A2.2 Operator training in purging procedure

A3. Igniting pilots before air is removed from system

Inadequate purge; lack of purge

Fire or explosion A3.1 Automated start up will not allow pilot ignition before system clear purge seal test*Control panel software

Failure Mode and Effects Analysis

• A method used to identify the ways a system can fail • Used for new and existing designs, products, processes and systems• Analyzes failures individually• FMEA identifies:

• Potential failure modes• Effects of failures• The causes of failures• How to avoid the failures

Failure Mode and Effects Analysis

Bow Tie Analysis

• A combination of a fault tree and event tree analysis • Used to provide a clear illustration of the risk pathways and control

measures• Provides a “big picture” view of a process or system to effectively

communicate risk exposures and controls• Attention to both preventive controls and reactive measures• Typically lacks a risk scoring mechanism

Bow Tie Analysis

‘Striped’ Bow Tie Analysis

Risk Matrix

• A means of combining qualitative or quantitative ratings of severity and likelihood to produce a risk level

• Used to rank risks as part of ‘risk evaluation’ • Provides a consistent method of prioritizing• Communicates risk to management

Risk Matrix

Using a Series of Risk Assessment Tools

Hazard ID:

Hazard Targets: Severity Probability Risk CodePersonnel

EquipmentDowntime

EnvironmentProduct

Hazard Targets: Severity Probability Risk Code Countermeasure codes:Personnel (D) Design alternation (E) Engineering (P) Process

Equipment (S) Safety Device (W) Warning (T) Training

DowntimeEnvironment

Product

Adapted from Advanced Safety Management: Focusing on Z10 and Serious Injury Prevention by Fred Manuele

Comments:

Prepared by: Reviewed by: Approved by:

Hazard Analysis and Risk Assessment

Initial Risk Assessment

Post-countermeasures Risk Assessment

Additional Countermeasures:

Hazard Description:

Exposure Interval: Activity/Process Phase: