Safety Cases_supplement E

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E1USING SAFETY CASES IN INDUSTRY AND HEALTHCARE

Tis is one of a series of supplements to the report: Using safety cases in industry and healthcare:a pragmatic review of the use of safety cases in safety-critical industries lessons and prerequisites fortheir application in healthcare

o access the report and the other supplements, please visit www.health.org.uk/safetycasesreport

Contents

1 Introduction E2

2 Regulatory context and best practice E2

3 Development and drivers E5

4 ypes o saety cases and content E7

5 Discussion E8

6 Lessons and recommendations or healthcare E8

7 Glossary E10

8 Reerences E10

Supplement E:

Safety case use in

the petrochemicalindustryJamie HendersonHuman Reliability Associates


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E2 THE HEALTH FOUNDATION

Tis summary is written rom the perspective o theEuropean, and specifically the UK, petrochemicalindustry, as these are the territories with which theauthors are most amiliar.

In the petrochemical industry, saety cases areprimarily developed to assist in the prevention omajor accidents. A major accident is defined as:

an occurrence (including in particular,a major emission, fire or explosion)

resulting from uncontrolled developmentsin the course of the operation of anyestablishment and leading to seriousdanger to human health or theenvironment, immediate or delayed,inside or outside the establishment,and involving one or more dangeroussubstances Control of Major AccidentHazards (COMAH) Regulations (1999)1

Tese events have a low probability o occurrencebut their consequences are potentially high, withthe possibility o multiple atalities both on andoff site. Historically, analyses in saety cases orinstallations have ocused on these types o events.One review o high-cost petrochemical accidents,covering the 22 years since the 1974 Flixboroughdisaster, identified 20 accidents with a cost o 1.5million or greater (at 1996 prices) in the UK alone.2

However, until relatively recently, saety metrics

in the UK petrochemical industry have beentargeted almost exclusively at what has becomeknown as occupational safety(eg injuries arisingrom slips, trips and alls, or manual handling).

One possible reason or this measurement ocusis that these types o event have a relatively highprobability o occurrence, making it easier or sitesto meaningully measure perormance. For example,sites ofen have signs indicating how many dayshave passed since a lost time injury. A realisationthat such measures may not provide the bestindication o whether a site is likely to suffer a majoraccident has resulted in a new effort to identiy andmeasure precursor indicators o major accidents.3

2 Regulatory contextand best practiceIn the UK, the legislation that governs therequirements related to saety cases in thepetrochemical industry is different or onshoreand offshore acilities. Offshore installations aresubject to the Saety Case Regulations (SCR),4,5onshore establishments are covered by the Controlo Major Accident Hazards Regulations (COMAH).

Te SCR came into orce ollowing the LordCullen inquiry into the 1988 Piper Alpha disaster.6Tere are many similarities between the SCR andCOMAH legislation (unortunately, however, theterminology is different the SCR legislation reersto saety cases, whereas the COMAH legislationreers to saety reports). Tereore, in the interestso brevity, this summary ocuses on the COMAHlegislation.

Supplement E:

Safety case use in the

petrochemical industry1 Introduction


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Te Control o Major Accident HazardsRegulations 1999 came into orce on 1 April1999 and were amended by the Control o MajorAccident Hazards (Amendment) Regulations 2005.7COMAH regulations implement Council Directive96/82/EC, known as the Seveso II Directive, as

amended by Directive 2003/105/EC and replacedthe Control o Industrial Major Accident HazardsRegulations 1984 (CIMAH). Tis section sets outthe requirements or saety cases in the context othis legislation. Issues related to previous legislationand the historical development o this legislation ina European context are discussed in the ollowingsection. Te inormation in this section is, unlessotherwise stated, a summary o inormation takenrom the legislation.

In the UK, the competent authority (CA) isresponsible or the enorcement o the COMAHregulations. Te CA comprises three organisations:the Health and Saety Executive (HSE), theEnvironment Agency (EA) and the ScottishEnvironmental Protection Agency (SEPA). TeHSE website8describes how the CA works in thecontext o UK health and saety legislation, whichis based on the principle that those who createrisk are best placed to manage it, and sets out

responsibilities or three key stakeholders:

Operators of COMAH sites have a responsibility

to manage risks arising rom their activities.

Emergency planning authorities have a

duty to ensure that off-site emergency plans are

prepared and adequate.

Competent authority assesses saety reports

submitted by site operators, inspects sites

and investigates incidents. It has the power to

prohibit operation where there is evidence that

measures taken or prevention and mitigation o

major incidents are seriously deficient. Te CA

charges the operators ees or services.

In the COMAH regulations, sites are designatedas top-tier or lower-tier based on the inventorieso dangerous substances they hold. Te thresholdquantities or each tier are specified in theregulations. Tereore, or example, a site with an

inventory o more than 500 tonnes o methanolwould be a lower-tier site, whereas a site holdingmore than 5,000 tonnes would be top-tier.Currently, there are around 650 lower-tier sites and375 upper-tier sites in the UK.9

In COMAH, saety cases are reerred to as saetyreports. Only top-tier sites are required to completea ull saety report. However, lower-tier sites arerequired to develop a major accident preventionpolicy, including an overview o their saetymanagement system. Te authors are currently

working with one lower-tier site that has developeda ull saety report despite their inventories notrequiring it. Tey have chosen to do this as theiroperating context sees them interacting with top-tier sites. Te main purposes o a saety report, as

set out in the legislation, are to demonstrate that:

an installation-specific major accident

prevention policy, and a saety management

system or implementing it, are in place

major accident hazards have been identified andthat the necessary measures have been taken

to prevent such accidents and to limit their

consequences

adequate saety and reliability principles and

saeguards have been incorporated into the

design, construction, operation and maintenance

o an installation

on-site emergency plans have been developed,

and that inormation has been supplied to enablethe development o off-site emergency plans.

Te principal requirements or COMAH sites, inaddition to a general obligation to take all measuresnecessary to prevent major accidents and limittheir consequences, are summarised in able E1,overlea.


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Table E1: Principal requirements for COMAH sites

Requirement Notes

Produce aMajor Accident

PreventionPolicy (MAPP)

he MAPP should: be proportionate to the hazards presented by the establishment.

set out aims and principles o action with respect to major accident hazards (MAHs).

demonstrate that a saety management system (SMS) is in place to determineand implement the MAPP (including coverage o the ollowing: roles andresponsibilities, identification and evaluation o MAHs, operational control,management o change, planning or emergencies, monitoring perormance andaudit and review).

Notiy thecompetentauthority

Sites are required to speciy the dangerous substances present at the site and describethe activities that are planned to take place.

Produce a saetyreport*

For top-tier sites, the saety report should contain the MAPP, including the saetymanagement system demonstration, as well as the ollowing inormation:

A description o the installation (including, or example, geographical location,activities which could result in a major accident, a description o the processes, aninventory o dangerous substances).

A detailed description o possible major accident scenarios (including theirprobability, a summary o triggering events, an assessment o severity andconsequences, a description o technical parameters and saety equipment).

A description o protection and intervention measures (including equipment,

alerting systems, and mobilisable resources). Saety reports should be reviewed at least every five years, or when new acts

emerge, or whenever the operator makes a change to the saety management system.

Produce anemergency plan*

op-tier sites should produce an on-site emergency plan that sets out: roles and responsibilities

or oreseeable events, a description o actions which should be taken to controland limit their consequences

how warning systems are expected to unction

the interace with the local authority responsible or setting the off-site plan in action arrangements or training staff in emergency duties.

In addition, an o-site emergency plan should also be developed by the localauthority. he legislation requires that both parts o this plan should be reviewedevery three years and that the plan should be tested.

Provideinormation*

op-tier sites are required to: provide inormation to the public (eg regarding how the population will be warned

o a major accident)

provide inormation to the competent authority (eg in response to requests or to

inorm them o a major accident).

* Tese steps are only required or top-tier sites.


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Te predictive elements o a COMAH saety reportshould demonstrate that measures have been takento reduce the likelihood o hazards, and to mitigatetheir consequences, until the associated risks areas low as reasonably practicable (ALARP). Ingeneral, the greater the hazard, and associated risks,

the more the operator o a acility should avouradopting additional measures, unless a cost-benefitanalysis suggests otherwise. Te HSEs SaetyReport Assessment Manual10states:

If all reasonably practicable measuresare in place, and the risks are tolerable,then there is nothing more to be done Individual Risk and Societal Concernmust be ALARP.

Te requirement or the saety report is that itshould provide evidence and a depth o argumentthat is proportionate to the risk posed by theestablishment. More detail regarding ALARP andtolerability o risk is provided in the HSE guidancedocument, Reducing Risks, Protecting People.11

In terms o measures specified in saety reportsor managing risk, a key standard is IEC 6151112(Tis is the process industry-specific version o IEC61508:199813). Tis is concerned with the unctionalsaety o saety instrumented systems (SIS) thatmight, or example, be specified as a risk control

measure to automatically shut down a processoperation, in the event o an abnormal situation,to prevent a hazard being realised. Te HSE SafetyReport Assessment Manual (SRAM) requires that aselection o SIS linked to major accident scenariosshould be provided in the saety report.

3 Development and driversIn Europe, the history o saety cases and saety caselegislation has been closely linked to the history ohigh-profile accidents.

In particular, the 1976 Seveso accident, at a smallchemical manuacturing acility in Italy, resultedin the development o legislation aimed at theprevention and control o major accidents. A simplechronology is presented in table E2 below.14

Table E2: Chronology of accidents

Date Event Notes and relationship to safety case requirements

1974 Flixborough disaster15 Large explosion kills 28 workers. Failure to use systematic analysisprocess to identiy hazards (eg HAZOP) identiied by the HSEinvestigation.16

1976 Seveso accident16 An uncontrolled exothermic reaction results in the release o a densevapour cloud containing poisonous and carcinogenic dioxin. ensquare miles o land are contaminated, more than 600 people areevacuated and 2,000 treated or poisoning.

1982 Seveso Directive isadopted

Council Directive 82/501/EEC on the major accident hazards ocertain industrial activities the so-called Seveso Directive isadopted.17Required substances to be identiied and processesdescribed. No requirement to include MAPP or saety managementsystem.

1984 Bhopal disaster18 A leak o gas and other chemicals rom a plant in India resulted inthe exposure o hundreds o thousands o people. Estimates on thedeath toll varied rom 2,000 to as many as 15,000 people.

1984 Control o Industrial

Major Accident Hazards(CIMAH) regulationsadopted in UK oronshore acilities

Superseded by COMAH regulations in 1999. Similar to Seveso I

requirements with an emphasis on description.


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Date Event Notes and relationship to safety case requirements

1987/1988

wo revisions o theSeveso Directive

hese amendments were aimed at broadening the scope o theDirective to include the storage o dangerous substances.

1988 Piper Alpha disaster6 An oil platorm that was later converted to gas production. An

explosion on the platorm and the resulting ire killed 167 men withonly 59 survivors.

1992 Saety case regulationsadopted or UK oshoreindustry

he publication o Lord Cullens report into the Piper Alpha disasterin 1990 paved the way or the introduction o ormal saety caserequirements in the UK oshore industry.

1996 Seveso II Directive isadopted

Implemented in the UK as the COMAH regulations (see below).

1999 Control o Major

Accident Hazards(CIMAH) regulationsadopted in UK oronshore acilities

Replaced the CIMAH regulations and introduced a greater degree o

uniormity with the oshore SCR. he regulations brought a numbero smaller sites under the legislation and introduced a number onew eatures, including the MAPP and saety management systemrequirements. Also brought an increased emphasis on demonstrationrather than description.

2003 Revision o Seveso IIDirective

Revision o Seveso II directive to include additional requirementsor risk assessment. he most important extensions o the scopecover risks arising rom storage and processing activities in mining,rom pyrotechnic and explosive substances, and rom the storage o

ammonium nitrate and ammonium nitrate-based ertilizers14

.

2005 Revision o saety caseregulations or UKoshore industry andCOMAH regulations

Te evolution o the saety report requirementsin the UK has not been without difficulty. In

particular, the change rom description under theCIMAH legislation to demonstration under theCOMAH legislation caused some conusion. Tisrequirement or demonstration placed the onuson operators o acilities to show that they weremanaging their risk using the ALARP concept.Te HSEs own website acknowledges some o thedifficulties with this approach:

Using reasonably practicable allows usto set goals for duty-holders, rather thanbeing prescriptive. Tis flexibility is a greatadvantage but it has its drawbacks, too.Deciding whether a risk is ALARP can

be challenging because it requires duty-holders and us to exercise judgement. In

the great majority of cases, we can decideby referring to existing good practicethat has been established by a process ofdiscussion with stakeholders to achieve aconsensus about what is ALARP. For highhazards, complex or novel situations, webuild on good practice, using more formaldecision making techniques, includingcost-benefit analysis, to inform our

judgement.19


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Initially, this was addressed in different ways byoperators (eg in terms o the maximum level orisk, in terms o cost-benefit analysis, or in termso the technology adopted) and consequently,the guidance on this concept, provided by thecompetent authority, evolved afer the submission

o the first batch o COMAH saety reports.20Tisissue illustrates the types o challenges that canbe aced by the authorities made responsible orassessing and responding to saety cases.

4 Types of safety casesand contento summarise, a typical COMAH saety report willcontain the ollowing elements:

major accident prevention policy (MAPP)

(including saety management system description)

an identification o hazards

analysis and assessment o risk (including

description o prevention/limitation measures)

an emergency plan.

Te COMAH regulations are goal-setting ratherthan prescriptive, in terms o the methods that

should be used to make these demonstrations.Tereore, a given saety report may include arange o different methods. Te ollowing sectionsprovide some examples o typical methods andapproaches that are used or the predictive aspectso the report (ie the identification o hazards andthe risk assessment).

Identification of hazardsTe COMAH Safety Report Assessment Manual

(SRAM)5provides some indication o the types oapproach that might be seen as acceptable or this

purpose:

Hazard and operability studies (HAZOP).

Saety review and studies o the causes o past

major accidents and incidents.

Industry standard or bespoke checklists or

hazard identification.

Failure mode and effect analysis (FMEA). Job saety analysis (eg task analysis).

Human error identification methods.

Whatever approach is used, firstly, according tothe SRAM, the report should demonstrate a clearunderstanding o the site operations, the materialsinvolved and the process conditions. Secondly, itmust identiy the hazards to people on-site andoff-site and to the environment. Finally, there must

be an analysis o different ways the hazard can beeliminated, reduced in scale, realised and controlled.

Tere is a requirement that all oreseeable majoraccidents are identified by the hazard identificationexercise. However, these may be organised intogroups to make the risk assessment easible. I thisis the case, the identified scenarios should be shownto dominate the risk and should include worst-casescenarios.

Analysis and assessment of riskFollowing the hazard identification the SRAMsuggests that, or the hazards that remain, theollowing activities should take place.

Tere must be a prediction o the likelihood

o the hazards being realised, taking account

o the chance o success and ailure o possible

preventative measures.

A prediction o the corresponding consequencesboth when the mitigation measures work and

ail.

An analysis o the risks associated with the

remaining hazards and the options or reducing

them.

A decision about which measures need to

be implemented to make the risks to people

(individually and collectively) and the

environment satisy the ALARP criteria.

A presentation o the results o the risk

assessment to provide the evidence and

arguments which demonstrate that all measures

necessary have been taken to prevent and

mitigate major hazards.

Te COMAH regulations do not state whetherqualitative, semi-qualitative or quantitativearguments should be used. Instead, there is arequirement or the operator to use methods that

are most appropriate or the risk involved. TeSRAM suggests some techniques that may be usedto develop requency and probability estimates:


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Relevant operational and historical data.

Fault tree analysis (FA).

Event tree analysis (EA).

IEC 6151110provides useul detail or managingrisk in relation to the concept o protection layers.

Part 3: Annex C o this guidance describes howprotective systems can be characterised as safetylayers. In this characterisation, the process hasa number o protection layers (ie the processcontrol system, alarms, SIS, relie devices, physicalprotection and emergency response) that combineequipment and administrative controls to controland mitigate process risk. Annex F describes layero protection analysis (LOPA), a semi-qualitativemethod, as a ormal process or considering

initiating causes (eg as identified in a HAZOPstudy) and the protection layers that prevent ormitigate the hazard. Tis process can be usedto determine the total existing amount o riskreduction and the need or urther risk reduction.Te LOPA approach allows or the identification othe appropriate saety integrity level (SIL) or thesaety-instrumented unction.

5 DiscussionIt seems that there are two issues o concern:the first is whether or not saety cases havemade an improvement to saety perormance inpetrochemical industries. I this is the case, thenthe next question is the degree to which the type osaety case regime in place or the petrochemicalindustries would be transerable to a healthcaresetting. Tis issue is addressed in the next section.

With regard to the first question, there is little hard

evidence to support the proposition that saety caseshave made an improvement to saety perormancein the petrochemical industry. We are unaware

o any research that demonstrates such a link.However, their application, in much the same wayas or accident investigation, has high ace validity.Certainly, it would be difficult to argue that reviewinghazards and assessing risks could have anythingother than a positive impact on saety perormance.

However, saety report development is a potentially

onerous activity or the establishments concerned.Tis is particularly the case in a goal-settingenvironment where the onus is on the operatorsthemselves to demonstrate that they are managing

risk. Tere may be a danger, or example, o anorganisation employing an external consultancy todevelop a standard report that does little to engagethe operator in the review o risks at their acility.

A continuing challenge is dealing with the low

probability nature o the major accidents that thesaety report seeks to address. Te industry iscurrently engaged in an effort to identiy processsaety indicators that may more accurately indicatesites that are vulnerable to major accidents.3

6 Lessons and recommendationsfor healthcareTe predominant historical driver or the initiationand development o a saety case regime in thepetrochemical industry has been major accidents(eg Seveso, Bhopal, Flixborough, Piper Alpha).Tese accidents have ofen had an impact beyondthe immediate acility and been extensively coveredby media outlets. Tis, in turn, has prompted awider discussion about the risks society is willingto tolerate in exchange or the benefits that suchendeavours bring. In the UK, or example, theHSE has published its criteria or decisions relatedto the regulation o risk in the context o changes

in the preerences, values and expectations osociety.9Te healthcare sector, however, doesnot have the dubious benefit o such high-profileincidents to drive the requirement or saety cases.Major accidents in the petrochemical industryare, or want o a better description, ofen visuallyspectacular events with the potential or widespreadharm and damage to the environment. Majoraccidents in a healthcare setting are most likely toharm an individual and take place, potentially, in

a context o ill-health where deterioration is notunexpected. Tis, o course, may change, and thereare examples o high-profile medical accidents.However, i high-profile accidents really havebeen the primary driver or the adoption o thesetechniques in the petrochemical industry, thenhealthcare may have to find other ways to promotea requirement or saety cases.

Saety cases are a regulatory requirement, but theyalso help organisations develop confidence that

they are adequately managing risks at their sites.In a healthcare setting it may be unlikely, atleast in the short term, that there will be asimilar regulatory push. Tereore, the benefits


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to healthcare organisations would need to beobvious in order to drive such a process. Tismay be difficult; our anecdotal experience in thepetrochemical industry is that regulation is themain influence on take-up o saety case analyses.Tis is not to say that there is a lack o interest in

saety perormance; the vast majority o individualshave a keen, motivated interest in the topic.However, these are complicated businesses thathave numerous goals related to production andsaety. Tereore, the activities that are pursuedtend to be those which have the highest priorityand, unsurprisingly, regulatory pressure is asignificant actor in determining priority. Tisis particularly true o more novel aspects. Forexample, human actors issues are now addressed

by specialist inspectors rom the competentauthority. Until this happened, our experiencewas that site managers would appreciate the issuesrelated to human actors, but would be unwilling todivert resources to their management, as they hadnumerous other priorities. Tis altered as soon asthe regulator became clear that they were seriousabout requesting a systematic analysis o humanactors issues related to major accident hazard-critical tasks.

A urther significant challenge is posed by theresources required to develop COMAH saetyreports. Ideally, these reports would be livingdocuments; continuously maintained as a riskregister and a demonstration that the site ismanaging saety. However, the requirement ordemonstration in relation to the ALARP conceptmeans that reports ofen run to several hundredpages. Tey are typically complex documents thattake up considerable site time and effort to develop.

Moreover, many sites use external consultants toassist with the report development. It is unlikelythat such a level o effort would be possible tosustain without external regulatory pressure. Tereis also the question o whether such a ocus on theevent o saety report development is even desirable.For example, it is not difficult to imagine a situationwhere the development o the saety report detractsrom the day-to-day running o the plant.

Under the COMAH regulations, the requirementto complete a saety case is determined by ananalysis o the hazards present at a given site.In the petrochemical industry this is relativelystraightorward, as an assessment o inventorieso hazardous substances can readily be

perormed. However, or healthcare, such a simpledetermination o hazards is less straightorward.Without a detailed knowledge o the healthcareenvironment, one supposes that harm is most likelyto be realised during procedures perormed onpatients. Tis would suggest that certain procedureswith high potential harm might be classified in asimilar manner. However, i most procedures aregeneric to all hospitals, then such a classificationmay not add value.

In addition, i hospitals, or example, were askedto identiy their most hazardous procedures, thenthese could potentially be pre-identified (eg in thesame way that named substances are listed in theCOMAH regulations). Hospitals could then berequired to demonstrate management o risks inrelation to such procedures.

Regulation in the UK petrochemical industry isgoal-setting rather than prescriptive. Tis meansthat sites are ree to choose the analysis methodsthat they eel are most appropriate to demonstratetheir management o risk. One downside o thisis that more effort is required both rom theoperator, in terms o the saety case development,and the regulator, in terms o the review o thereport and the inspection o the acilities.


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7 Glossary

Term Notes

ALARP21 As low as reasonablypracticable

A concept involving weighing a risk against the trouble, time andmoney needed to control it.

FMEA22

Failure modes and eectsanalysis

A technique or evaluating the ways in which equipment can ail(or be improperly operated) and the eects these ailures canhave on a process.

HAZOP23 Hazard and operabilitystudy

A systematic method or the identiication o hazards andproblems that might prevent eicient operation o a plant.

LOPA24 Layers o protectionanalysis

A technique that can be used to assess the adequacy o thelayers o protection provided or an activity. his includes a riskanalysis that can be used to identiy saety unctions that need tobe put in place to reduce risk to a tolerable level.

SRAM10 Safety Report AssessmentManual

Manual used by HSE inspectors when assessing COMAH sites.

8 References1 Te Control o Major Accident Hazards Regulations 1999 No

743. Overview available at: www.hse.gov.uk/comah/background/

comah99.htm accessed February 2011.

2 Fewtrell, P. and Hirst, I.L. (1998) A review o high cost-cost

chemical/petrochemical accidents since Flixborough 1974.

IChemE Loss Prevention Bulletin. No 140.

3 Health and Saety Executive (2006) HSG254 Developing processsafety indicators: A step-by-step guide for chemical and major

hazard industries. HSE Books.

4 Te Offshore Installations (Saety Case) Regulations 1992 No

2885. Available at: /www.legislation.gov.uk/uksi/1992/2885/

contents/made accessed February 2011.

5 Te Offshore Installations (Saety Case) Regulations 2005 No

3117. Available at: www.legislation.gov.uk/uksi/2005/3117/

contents/made accessed February 2011.

6 Cullen, Te Honourable Lord (1990) Te Public Inquiry into the

Piper Alpha Disaster. HMSO.

7 Te Control o Major Accident Hazards (Amendment)

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accessed February 2011.

8 Health & Saety Executive. Te Competent Authority in Detail.

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February 2011.

9 Personal communication with HSE Hazardous Installations

Directorate, February 2011.

10 Health and Saety Executive (2006) COMAH Safety Report

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11 Health and Saety Executive (2001) Reducing Risks, ProtectingPeople: HSEs decision-making process. HSE books.

12 BS IEC 61511:2003 Functional saety Saety Instrumented

Systems or the process industry sector.

13 BS IEC 61508 1998 Functional Saety o electrical/electronic/

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14 Chemical Accidents (Seveso II) Prevention, Preparedness and

Response. European Commission. Available at: http://ec.europa.

eu/environment/seveso/index.htm accessed February 2011

15 Report o the Court o Inquiry (1975) Te Flixborough Disaster.

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17 European Commission: Environment. Chemical Accidents

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18 Morehouse, W. and Arun, M. (1986) Te Bhopal ragedy. Te

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implementation. Presentation made at the 34th meeting o

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Safety Cases_supplement E