HAZOP Study Methodology_2 IEDOSH JB - Student

HAZOP Study MethodologyIEDOSH JB

Semester MAY 2012Prepared by :

Mohd Ismafazil Ismail

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SCOPE OF THE STUDY

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BASIC PRINCIPLES

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HAZOP METHODOLOGY The application of a formal,

systematic and critical examination of the process and engineering intentions of a process design

Potential of hazard – assessed

Malfunction of individual items of equipment and the consequences for the whole system – identified

Involve a team that has experience in the plant or design to be studied

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HAZOP METHODOLOGY4 overall aims to which any HAZOP should be addressed

Identify all deviations from the way design is expected to work, causes, hazards & operability problems

Decide whether action is required to control the hazard/operability problem

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HAZOP METHODOLOGY

Identify cases where decision can’t be made immediately, any info/action required

Ensure actions are followed through

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HAZOP METHODOLOGY

Study may not be resolve all the hazards so firm recommendations for change cannot always be guaranteed to result from deliberation at a HAZOP meeting.

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HAZOP METHODOLOGY

Draft report – report summarizing the study & giving a list of recommendations together with work sheets.

Final report – giving details of follow-up actions to complete the study.

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HAZOP Study Procedure6 steps in the development of a HAZOP study :

1) Defining objectives & scope2) Select HAZOP team members3) Preparing for the study4) Undertaking the study5) Recording the results6) Conducting the follow-up

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1) Defining the objectives and scopeFactors will influence the study Objectives & Scope

o Nature & stage of the projecto Requirement for full documentationo Availability of personnelo Number of P&IDso Timing, duration & budgeto Degree of authority given

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P & ID

A Piping and Instrumentation Diagram - P&ID, is a schematic illustration of functional relationship of piping, instrumentation and system equipment components.

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P & ID

P&ID shows all of piping including the physical sequence of branches, reducers, valves, equipment, instrumentation and control interlocks. PID_sample

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1) Defining the objectives and scopeStudy influence the product

Check a design for hazards/operability

Decide whether & where to build

To buy an equipments Check running instructions Improve the safety of existing

facilities13

1) Defining the objectives and scopeTypes of hazard to be considered

To people working in a plant To plant & equipment To or from product quality To the general public To the environment

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2) Selecting the HAZOP team members• Detailed technical knowledge of the process.

• Those with knowledge and experience of applying highly structured, systematic HAZOP approach.

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3) Planning for the study

Session dates and times Documents to be studied in each session

Team members availabilityReporting arrangements Sub session plan Plan for follow up action

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4) Undertaking the studyA study team to consider part of a process design for a number of deviations & guidewords

7 stages1. Apply a guideword2. Develop a deviation3. Examine possible causes

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4) Undertaking the study

4. Examine consequences5. Consider

hazards/operability problem

6. Decide upon action7. Make a record of the

discussion & decision18

HAZOP – Hazard and operability

Hazard Identification

Consequence & Qualitative Risk

Recommendation for Mitigation HAZOP Cause

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HAZOP – Hazard and operability

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1st study session – team leader invites the process engineer to outline the design intentions in very broad terms. Required info on flow rates, pressures and temperature within sections.

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4) Undertaking the study Ensure team member has adequate knowledge of the process and the way section operated.

Guideword applied, discuss causes, consequences and possible actions for each deviation.

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2 extreme approaches :

(1)Solution found for each hazard as detected before looking for the next hazard

(2)No search of solution, all issues recorded with recommendations, issues be studied

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2 extreme approaches :

Study leader will sum up at the end of discussion before starting with next guideword.Maintain pace, terminate disagreement, resolve outside meeting, no prolonged discussion on solution.

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5) Recording the results Record the results (may

need a secretary) Follow-up of actions noted

› final report contain resolution of all recommended actions

› must appoint someone as leader to check progress of action

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5) Recording the results

› team may meet again if answers to questions do not simply lead to an action

› team may meet again if significant design changes in interim report

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6) Conducting follow up Prioritize the recommendation, giving

highest priority to the class which could be most sensitive to the company

Determine the type of recommendations : Rejected recommendations Procedural Small projects Additional study

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HAZOP - Procedure

HAZOP keeps all team members focused on the same topic and enables them to work as a team

NODE: Concentrate on one location in the processPARAMETER: Consider each process

variable individually (F, T, L, P, composition, operator action, corrosion, etc.) 28

HAZOP - Procedure

GUIDE WORD: Pose a series of standard questions about deviations from normal conditions. We assume that we know a safe “normal” operation.

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HAZOP - Procedure

NODE: Pipe after pump and splitter

PARAMETER*: Flow rate

GUIDE WORD*: Less (less than normal value)• DEVIATION: less flow than normal

• CAUSE: of deviation, can be more than one

• CONSEQUENCE: of the deviation/cause

• ACTION: initial idea for correction/ prevention/mitigation

A group members focus on the same issue simultaneously

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NodeEach P&ID is divided into smaller sections called nodes.

A node will typically contain a major piece of equipment plus associated piping and instrumentation.

Depending on the experience of the study leader, the portion of a process included in a single study node can vary.

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HAZOP - Hazard and operability

Identify nodes ?

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HAZOP Process Parameter

Flow Composition pHPressure Addition SequenceTemperature Separation SignalMixing Time Start/stopStirring Phase OperateTransfer Speed MaintainLevel Particle size ServicesViscosity Measure Communication Reaction Control

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HAZOP Guidewords with explanation

Guidewords Meanings Comments

No, Not or None The complete negation of the design intentions

No part of the intentions is achieved and nothing else happens

More of Quantitative increases of any relevant parameters

These refer to quantities + relevant physical properties such as flow rates and temperatures a well as activities like “HEAT” and “REACTION”

Less of Quantitative decreases

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Guidewords Meanings Comments

As well as A qualitative increase

All the design and operating intentions are achieved together with some additional activity

Part of A qualitative decrease

Only some of the intentions are achieved, some are not

Reverse The logical opposite of the intention

This is mostly applicable to activities for example, reverse flow or chemical reaction. It can also be applied to substances e.g. “POISON” instead of “ANTIDOTE” or “D” instead of “L” optical isomers

Other than Complete substitution

No part of the original intention is achieved. Something quite different happens.

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The first 3 guidewords (none, more of and less of ) – straightforward

Example : water system

Remaining 4 guidewords are tricky :

Qualitative deviations like “as well as” and “part of” allow all or part of the design intention to be retained.

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Ex : As well as substance A could mean

a) Some material is transferred as well as substance A

b) Substance A is transferred elsewhere as well as to the vessel being considered

c) Other activity takes place concurrently with the transfer of substance A. Ex : decomposition or a change of phase of the material.

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Ex : Part of transfer of substance A

a) Component of substance A missing

b) Substance A is transferred to other parallel vessel

Ex : Reverse transfer

c) Opposite of design intentions38


Ex : Other than transfer of substance A

a) A different substance is transferred

b) Substance A is transferred elsewhere

c) Activity halted due to solidification

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HAZOP Guidewords and Causes – Continuous operation

Guidewords Causes

No Flow Wrong routing – blockage – incorrect slip plate – incorrectly fitted check valve – burst pipe – large leak – equipment failure (CV, isolation valve, pump, vessel, etc) – incorrect pressure differential, etc

Reverse Flow Defective check valve – incorrect pressure differential – two way flow – emergency venting – incorrect operation, etc.

More flow Increased pumping capacity – increased suction pressure – reduced delivery head – greater fluid density – control faults – running two pumps, etc.

Less Flow Line restrictions, filter blockage – defective pumps – fouling of vessels, valves, etc.

More Level Outlet isolated or blocked – inflow greater than outflow – control failure – faulty gauge, etc

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Guidewords Causes

Less Level Inlet flow stops – leak – outflow greater than inflow – control failure – draining of vessel, etc

More Pressure Surge problems – connection to high pressure systems – gas breakthrough (inadequate venting), thermal overpressure, defective relief valves, etc

Less Pressure Restricted pump/compressor suction line – undetected leakage – vessel drainage – gas dissolving in liquid, etc

Less Flow Line restrictions, filter blockage – defective pumps – fouling of vessels, valves, etc.

More Temperature

Failed exchanger tubes – fire situations – cooling water failure – defective control – heater control failure – reaction control failures, etc

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Guidewords Causes

Less Temperature

Loss of heating – failed heat exchanger – reducing pressure, etc

More Viscosity Incorrect material or composition – incorrect temperature – high solid concentration, etc.

Less Viscosity Incorrect material or composition – incorrect temperature – solvent flushing, etc.

Composition Change

Leaking isolation valves – incorrect specification – inadequate quality control – process control upset, etc

Contamination Leaking exchanger tubes – incorrect operation of system – wrong additives – grade change, etc.

Relief Relief valve discharge location – inlet and outlet piping, etc

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Guidewords Causes

Instrumentation Control philosophy – response time – alarm & trip setting, auto/manual facility & human error, etc.

Sampling Sampling procedure and operator safety – time for analysis result – calibration of automatic samplers – loss of sample flow, etc

Corrosion/ Erosion Cathodic protection arrangements – internal/external corrosion – stress corrosion cracking, etc

Service Failure Failure of instrument air/ steam/ nitrogen/ cooling water/ hydraulic/ power – computers, etc

Abnormal Operation

Purging – flushing – clearing blockages – emergency shutdown, etc.

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Guidewords Causes

Maintenance Isolation philosophy – drainage – rescue plan – training – pressure testing, etc.

Ignition Grounding arrangements – flame arrestors – static electricity – hot surfaces – hoses, etc.

Spare Equipment Installed/non-installed spare equipment – availability of spares – modified specifications, etc

Safety Toxic properties of process materials – fire & gas detection system – contingency plan – emergency response plan, etc

Human Factors Layout - accessibility

HAZOP case studies at section 8.244

Guide word -Parameter

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Loss of containment (Part of)

– Piping failures from corrosion induced leaks or mechanical impact– Failures of flanges and fittings– Leaks from valve stems or pump seals– Heat exchanger tube rupture or shell failure– Pressure vessel failure– Releases from small bore fittings, instrument bridles, drains and vents– Materials of construction, corrosion

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Utilities failures (Part of)– Instrument Air or Nitrogen– Power– Cooling water or Steam failure– Fuel Gas or Fuel Oil failures

Environment impact– Lightning, Wind or Flood– Earthquake– Noise

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Testing– Equipment such as alarms, trips PRV settings– Product or intermediate sampling and analysis

Maintenance (Other than)– Access and means of isolation– Draining, Purging and drying– Cooling or warming of equipment– Availability of spares/replacement items– Special activities (for example Hot Tapping)

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Electrical– Area classification– Isolation and earthing

Instrumentation– Suitability/reliability/sufficiency of sensors and transmitters– Location, failure modes and effect on any voting logic– Alarms, hierarchy and ability of operator to respond

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Personnel protection

– Basic equipment, boots, hard hats, gloves goggles– Escape masks, breathing apparatus (Toxics or confined entry)– Permit to work and requirements (escape routes, ladders, ropes etc)– Protective instruments (oxygen analysers, flammable /toxic gas detectors)

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Plant protection– Fire and smoke detection– Flammable or toxic gas detection– Firewater systems, monitors, deluges and sprays– Passive fire protection– Chemicals storage and handling– Fences and measures against intruders, saboteurs– Housekeeping

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Deviation table

Deviation Column Tank/Vessel LineHeat

Exchanger Pump

High Flow X

Low/no Flow X

High Level X X

Low Level X X

High Pressure

X X X

Low Pressure X X X

High Temp. X X X

Low Temp. X X X

High Concen. X X X

Low Concen. X X X

Reverse Flow X

Tube Leak X

Tube Rupture X

Leak X X X X X

Rupture X X X X X52

Guide word –Parameter Exercise

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Preliminary HAZOP ExampleRefer to reactor system shown.

The reaction is exothermic. A cooling system is provided to remove the excess energy of reaction. In the event of cooling function is lost, the temperature of reactor would increase. This would lead to an increase in reaction rate leading to additional energy release.

The result could be a runaway reaction with pressures exceeding the bursting pressure of the reactor. The temperature within the reactor is measured and is used to control the cooling water flow rate by a valve.

Perform HAZOP Study

TC

Cooling Coils

MonomerFeed

Cooling Water to Sewer

Cooling Water In

Thermocouple

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Preliminary HAZOP on Reactor - Example

Guide Word Deviation Causes Consequences Action

NO No cooling Temperature increase in reactor

REVERSE Reverse cooling flow

Failure of water source resulting in backward flow

MORE More cooling flow

Instruct operators on procedures

AS WELL AS Reactor product in coils

Check maintenance procedures and schedules

OTHER THAN Another material besides cooling water

Water source contaminated

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Case Study – Shell & Tube Heat Exchanger

• Using relevant guide works, perform HAZOP study on shell & tube heat exchanger

Processfluid

Cooling water

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Less Less flow of cooling water

Temperature of process fluid remains constant

More More cooling flow

More of More pressure on tube side

Install high pressure alarm

Contamination Contamination of process fluid line

Proper maintainance and operator alert

Corrosion Corrosion of tube

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NONE No cooling water flow

Process fluid temperature is not lowered accordingly

MORE More cooling water flow

LESS Less cooling water

Installation of flow meter

REVERSE Reverse process fluid flow

Install check valve (whether it is crucial have to check?)

CONTAMINATION

Process fluid contamination

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Espresso Machine - Exercise

(B) Water tank

(H) Electrical Heating

(L) Connecting pipe

(K) Coffee reservoir

(T) Cup

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Espresso Machine1. Filling

Fill 100 ml water into the water tank and close the lid.

2. Feed coffeeFeed the coffee reservoir with 10 g of coffee and screw it onto the discharge line.

3. HeatingHeat to boiling by switching on.

4. DischargePress hot water through the coffee into the cup.

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Operating Procedure HAZOP

A procedure HAZOP is an examination of an existing or planned operation (work) procedure to identify hazards and causes for operational problems, quality problems, and delays.

• Can be applied to all sequences of operations

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• Focus on both human errors and failures of technical systems

• Best suited for detailed assessments, but can also be used for coarse preliminary assessments

• Flexible approach with respect to use of guide-words

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• Breakdown of operation (work) procedure to suitable steps

• Define intention of each step

• Establish boundary conditions

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else asconventional Process HAZOP

• Apply guide-words to intention and boundary conditions for each step.

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Operating Procedure HAZOP• Team should identify the

intent of the procedure• Understand the state of the

equipment at the beginning and end of the procedure

• Know objective of the procedure and overall in detail

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• Study will be carried out in a ‘step by step’ manner

• Review the step as requiring an action at a time in a sequence

• Review the wording of the instructions as a flow of information

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Operating Procedure HAZOP• The procedure is a set of instructions

whose aim is to direct an operator to make changes to the state of a system in a safe manner.

(a) Commissioning(b) Start – up(c) Normal shutdown(d) Emergency shutdown(e) Preparation for maintenance(f ) Sampling/tapping/draining(g) Inspection/monitoring/checking

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Procedure HAZOP Guidewords and Issues

Guideword

ACTI ON TI ME SEQUENCE I NFORMATI ON

None x x

Reverse (wrong) x x

More x x x

Less x x x

Part of x

As well as x

Other than x x

Parameter

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Guidewords Causes

Purpose Is the step needed? – is the intent of this step clear? – can this step be miss applied?

No Action Step is missed or omitted – action impossible – equipment not ready (Locked out/ not in service)

More Action Operator does more than intended (opening valve too far) other actions occur affecting this operation

Less Action Operator does less than intended (added less catalyst than required) – not enough time to complete the step

Wrong Action Operator open the wrong valve – starts the wrong pump – reads the wrong instrument

Part of Action Operator only completes part of a composite action (misses out middle part or final part)

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Guidewords Causes

Extra Action Operator assumes he is required to do something in addition to what is specified – poor communication - other procedure interfering

Other Action Operator misunderstands instruction and does something completely different

More Time Operator takes longer than necessary over action – start next action later than expected

Less Time Operator carries out action too quickly (stop the flow before required level is reached)

Out of Sequence

Operator misses out a step – carries out a step before it should occur or after it should occur

More Information

Procedure includes information that is unnecessary and could lead to confusion – contains information that contradicts other information

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Guidewords Causes

Less Information Necessary information is missing from the procedure – information about the starting condition – information which allows operator to check progress or to troubleshoot problem

No Information No feedback from the process (transmitter failure) – not specify standard operating conditions (temperature, pressure, flow)

Wrong Information

Out of date – contradiction (oral vs written, other procedures within this procedure)

Clarity Step confusing – poor procedure from layout

Unattended Safeguards – adequate information feed-back (alarms, signals)

Operation Remote – starting equipment – emergency response (time, personnel, equipment)

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Guidewords Causes

Training Adequate training – is certification required and provided for this step – procedure control

Abnormal Emergencies – recovery from abnormal situations

Conditions Failure – severe or unusual weather

Maintenance Work permit required – equipment conditions - recalibrations

Safety Personal protection – OSHA compliance – industrial hygiene – environmental considerations – fire, explosion or chemical release potential

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Procedure HAZOP exercise

Please perform Procedure HAZOP using the guidewords


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HAZOP

HAZOPNodes

ParametersGuide words

Consequence

Deviation

All of these terms! This stupid table!I hate HAZOPS. Why don’t we just

learn the engineering?

ATTITUDE CHECK

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HAZOP

I suppose that I should have done that

HAZOP Study!

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HAZOP log sheet

HAZOP log sheet

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Log sheet Node/Section

A node is a specific location in the process in which (the deviations of) the design/process intent are evaluated.

Examples might be: separators, heat exchangers, scrubbers, pumps, compressors, and interconnecting pipes with equipment.

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Log sheet Design Intent

The design intent is a description of how the process is expected to behave at the node; this is qualitatively described as an activity (e.g., feed, reaction, sedimentation) and/or quantitatively in the process parameters, like temperature, flow rate, pressure, composition, etc.

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Log sheet Deviation

A deviation is a way in which the process conditions may depart from their design/ process intent.

Parameter

The relevant parameter for the condition(s) of the process (e.g. pressure, temperature, composition).

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Log sheet Guideword

A short word to create the imagination of a deviation of the design/process intent. The most commonly used set of guide-words is: no, more, less, as well as, part of, other than, and reverse. In addition, guidewords like too early, too late, instead of, are used; the latter mainly for batch-like processes.

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Log sheet GuidewordThe guidewords are applied, in turn, to all the parameters, in order to identify unexpected and yet credible deviations from the design/process intent.

Guide-word + Parameter = Deviation

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Log sheet Cause

The reason(s) why the deviation could occur. Several causes may be identified for one deviation. It is often recommended to start with the causes that may result in the worst possible consequence.

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Log sheet Consequence

The results of the deviation, in case it occurs. Consequences may both comprise process hazards and operability problems like plant shut-down or reduced quality of the product.Several consequences may follow from one cause and, in turn, one consequence can have several causes

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Log sheet Safeguard

Facilities that help to reduce the occurrence frequency of the deviation or to mitigate its consequences. There are, in principle, five types of safeguards that:

1. Identify the deviation (e.g., detectors and alarms, and human operator detection)

2. Compensate for the deviation (e.g., an automatic control system that reduces the feed to a vessel in case of overfilling it. These are usually an integrated part of the process control)

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Log sheet

3. Prevent the deviation from occurring (e.g., an inert gas blanket in storages of flammable substances)

4. Prevent further escalation of the deviation (e.g., by (total) trip of the activity. These facilities are often interlocked with several unitsin the process, often controlled by computers)

5. Relieve the process from the hazardous deviation (e.g., pressure safety valves (PSV) and vent systems) 85

HAZOP Study

HAZOP study are applied during :

• Normal operation

• Foreseeable changes in operation, e.g. upgrading, reduced output, plant start-up and shut-down

• Suitability of plant materials, equipment and instrumentation

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HAZOP Study

• Provision for failure of plant services, e. g . steam, electricity, cooling water

• Provision for maintenance.

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Strength of HAZOP• HAZOP is a systematic, reasonably

comprehensive and flexible.• It is suitable mainly for team use

whereby it is possible to incorporate the general experience available.

• It gives good identification of cause and excellent identification of critical deviations.

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Strength of HAZOP

• The use of keywords is effective and the whole group is able to participate.

• HAZOP is an excellent well-proven method for studying large plant in a specific manner.

• HAZOP identifies virtually all significant deviations on the plant, all major accidents should be identified but not necessarily their causes.

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Weakness of HAZOP• HAZOP is very time consuming and can

be laborious with a tendency for boredom for analysts.

• It tends to be hardware-oriented and process-oriented, although the technique should be amenable to human error application.

• It tends to generate many failure events with insignificance consequences and generate many failure events which have the same consequences. 90

Weakness of HAZOP• It stifles brainstorming although this is

not required at the late stage of design when it is normally applied.

• HAZOP does not identify all causes of deviations and therefore omits many scenarios.

• It takes little account of the probabilities of events or consequences, although quantitative assessment are sometime added. The group generally let their collective experiences decide whether deviations are meaningful.

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Weakness of HAZOP

• HAZOP is poor where multiple-combination events can have severe effects.

• It tends to assume defects or deterioration of materials of construction will not arise.

• When identifying consequences, HAZOP tends to encourage listing these as resulting in action by emergency control measures without considering that such action might fail. It tends to ignore the contribution which can be made by operator interventions

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Mechanistic procedure• At the beginning of a study, leader should

choose small, simple section of equipment & piping to review.

• If pre-planning done, always be on the basis of simple sections until leader confident with the team capabilities

• Leader should ensure consensus before moving to next point.

• Moving rapidly to next cause can inhibit another not so quick team member

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Mechanistic procedure• It is helpful to list all causes of a

particular g/word before moving to consequences.

• Leader should check causes is real & not just restatement of deviation.

• It similarly applies to consequences

• When scenario identified where expected a serious consequences, team should decide which risks are acceptable & vice versa.

• Often helpful to have a relatively philosophical discussion as preferences

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Mechanistic procedure• When insufficient information is available,

record an action to review the section at specific date.

• Major redesign, record the design parameters & note further review is required.

• Assign ‘checking’ issues to a team members

• If P&ID is out of date, study stop until get new updated version

• Handicapped by lack of info, stop discussion & assign ‘checking’ duty

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Process Hazard Assessment - best practice

Concept Stage Risk Assessment

Conceptional Design

Basic Risk Assessment

Process Flow Sheet Development

Detailed Risk Assessment

Piping & instrumentation Diagram Development

Construction Design Verification

Pre-commissioning Assessment

Hand Over

PRAstep 1

PRAstep 2

Mechanical Completion

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Process Hazard Assessment - best practice

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Hand OverPre-operations Inspection

Post Start-up Assessment

Start of Operation

Risk Assessment Revalidation

Change

Normal OperationPRAstep 3

Concept Stage Risk Assessment Definition

Concept Stage Risk Assessmentis an early systematic investigation on safety, health, environment issues relevant to the project

This assessment defines: Scope of project Process description Material hazards Involvement of external authorities Organization and human factors Additional assessments

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Concept Stage Risk Assessment Method

Application of inherent SHE to -Eliminate the use of hazardous materials

-Minimize production of waste-Process conditions (pressure, temperature, etc.)

Review previous incidents on similar processes or plants

Collect information on hazards of chemicals involved

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Concept Stage Risk Assessment Method

Review Environmental and Occupational Health Statements

Consider Interaction of the project with site activities

Review application of local legislation

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Basic Risk AssessmentDefinition

Basic Risk Assessment is an systematic approach to :

Define the main hazards of a project

Assess probability and severity

Define the basis of safe operation regarding- Toxics- Fire and explosions- Exothermic reactions

Specify the need for corrective actions

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Basic Risk AssessmentMethod

Use of a guide tool to:

Identification of main hazards like - Explosion- Fire- Toxic release (loss of containment)- Uncontrolled exothermic reaction

Identification of consequences and related probabilities

Identify the need for additional protective systems

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Detailed Risk Assessment Definition

Detailed Risk Assessment is an systematic approach to:

Identify hazards that arise from deviation from design intend

Assess probability and severity of such deviations

Specify the need for additional safeguards

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Detailed Risk Assessment Method

Structured use of guidewords to assess possible deviations and their consequences:

a. A firm reviewed Piping and Instrument Diagram (P&ID)b. Lay-out sketch c. Process descriptiond. Process control procedure e. Material characteristics (MSDS)f. Area electrical classification drawings (zoned areas)g. Interlocking diagram and SIL classificationh. Outline operating, commissioning, maintenance and test

proceduresi. Operating instructionsj. Relief systems philosophy

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Detailed Risk Assessment Method

Structured use of guidewords to assess possible deviations and their consequences:k. Actions/recommendations from basic risk

assessment l. Specification of vessels and pipe work requiring

periodic inspectionm.Provision of a list of critical machine systemsn. In addition, for batch processes a full sequence

description is requiredo. Plant tour (to confirm that the above mentioned

documents are in line with the existing equipment)

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Construction/design Verification Definition

Construction/design verification is a pre commissioning check that hardware has been built as intended.

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Construction/design Verification Method

Use of a check list for: Installation check

Check that the hardware is as the design intended and that the software requirements are completed

Implementation checkCheck that what was called for in earlier hazard studies and engineering change orders has been implemented

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Construction/design Verification Method

Use of a check list for:

Modification CheckCheck that modifications made during construction/commissioning have been formally reviewed and documented

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Pre-commissioning Assessment Definition

Pre-commissioning Assessment is an systematic site inspection to ensure that the plant is a safe place to work and meets company and legislative requirements before hand over to operation.

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Pre-commissioning Assessment Method

Key aspects include an assessment of:

Arrangements for the protection of employee health, covering the facilities provided and the arrangements for workplace monitoring

Arrangements, including emergency systems, for employee safety

Equipment and systems provided to protect the environment and for monitoring environmental performance

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Post Start-up Assessment Definition

Post start-up Assessment is a formularized review meeting 3-6 month after start-up. Purpose of this assessment meeting is to review the initial running period and to provide feedback to engineering of the plant’s performance.

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Post Start-up Assessment Method

Use check list to ensure that: Previous risk assessments have been

completed and documented Early operation has been reviewed and

confirmed that it is consistent with the design intent with regard to safety, health and environmental issues, and that assumptions defined in earlier assessments are borne out in actual operation

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Post Start-up Assessment Method Operating and maintenance difficulties

have been reported and documented, and ensure feedback to the design engineering organization responsible for the project

Modifications during start-up have been reviewed, approved and documented

Performance of trip and alarm system has been reviewed

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Risk Assessment Revalidation Definition

Risk Assessment Revalidation is a formularized review of the process safety

Upon any change (process, equipment, raw materials, …)

Following an incident

Operational learning

Change in legal or Henkel requirements

After 5 years

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Risk Assessment Revalidation Method

Use of a standardized proceeding to ensure that: Opportunities for hazard reduction or elimination

and risk reduction are considered Process risk control measures are sufficient for

the continued operation of the plant Process risks for which the control measures are

no longer sufficient and which require action are identified

Legal and Henkel requirements are met

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THANK YOU

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