Health and Safety Executive
Health and Safety Executive
Major Accident Hazards
Linda Donachie
HM Principal Inspector of
Health and Safety
What I will cover…………………
COMAH SITES AND MAJOR ACCIDENT PREVENTION
REGULATION OF COMAH SITES
THE ROLE OF THE CONTRACTOR IN PREVENTION OF MAJOR ACCIDENTS
ANY GENERAL QUESTIONS
What is a contractor?
• Temp workers/Agency workers
• Specialists – IT, C&I, Electrical, NDT
testing of tanks, PSSR/LOLER examiners
• Consultants – Assistance with Safety
reports etc
• Water treatment company (cooling tower
management)
• Construction projects
Major Accidents involve……..
• A dangerous substance
• A loss of control
• Serious harm or risk of serious harm to
people and
environment…………………….
THE REGULATORY APPROACH
Inspection
Safety Report Assessment
Investigation
Stakeholder engagement
……….leading to
»Advice
»Enforcement
»Prosecution
Regulation
• Control of Major Accident Hazard
Regulations 1999 (as amended)
- the operator of a COMAH site shall take
all measures necessary to prevent major
accidents and limit their consequences to
people and the environment-
- parallel duties on other organisations that
work on site (under HSAWA)
Major Hazard Management Systems
People Processes
Plant
Risk Assessment
Risk Profile
Loss of Control
OutcomeMAJORHAZARD
Preventive Barriers Mitigation Barriers
Determine the Control Measures (Barriers)
Major Hazard Control Measures (Barriers)
Potential
Impact/
Consquences
Probability
Challenges to
Integrity or
Containment
Corrosion
High/LowPressure
Overfilling
Human Error
Physical Damage
High/LowTemperature
CHECK,MEASURE& REVIEW
Leading & lagging indicators to measure performance of control
measures
Audit Programme to check the design and suitability of control
measures
Investigate loss of containment events and major hazard incidents to identify failures in the control
measures
MAJOR HAZARD MANAGEMENT
(the big picture)
Hazard IdentificationProcesses or
Activities
Undertaken
Hazardous-
Property:
Condition
Volume
Activity/ Processes:
Storage
Reacting
Separating, Distillation
Mixing, Blending
Product Transfer
Propagating
Concentrating
Plant Life
CycleStart-up
Operate
Modify
Shutdown
Toxic
Flammable
Reactive
Corrosive
Explosive
Infectious
Temperature
Pressure
Solid
Liquid
Gas
Intrinsic Hazard
Physical PropertyFor example:
Stage in Plant Life Cycle – where relevant
LeadershipTo set an effective vision
ans culture for major hazard management
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Barriers are a combination of PPP People Processes
Plant
Loss of
ContainmentOutcomeMAJOR
HAZARD
Preventive Barriers Mitigation Barriers
Process Safety Control Measures (Barriers)
PLANT INTEGRITY
• INSPECTION
• MAINTENANCE
PROCESSES
• CONTROL SYSTEMS
• REMOTE ISOLATION
PEOPLE
• PERMIT TO WORK
• SAFE PROCEDURES
• COMPETENCE
RISK ASSESSMENT
PROCESS
MAINTENANCE REGIME
SELECTION OF
CONTRACTOR
QUALITY OF SITE WORK
AUDIT/REVIEW PROCESS
LATENT FAILURE
LOSS OF CONTAINMENT OF
HYDROCARBON
Scaffolders working on petrochemicals plant
suffered effects of inhalation of
hydrocarbons in the area they were working
in when a small instrument branch line
appeared to have sheared off and 3 tonnes
of highly flammable liquids was lost to
atmosphere.
Conclusions
• Activities undertaken on behalf of the operator by contractors are a fundamental part of the operation of most COMAH establishments
• Contractors form an integral part of the overall safety management system and should be accorded the same respect/standards as employees in the work they are required to do
• Are often at the “sharp end” of an incident
• Contractors should be proactive in identifying whether their work forms part of a safety critical plant and process
Guidance
• HSG159 – Managing contractors –
A Guide for Employers
• INDG368(rev1) Using Contractors -
A Brief Guide
• http://www.hse.gov.uk/humanfactors
/topics/contractorisation.htm
• http://www.hse.gov.uk/humanfactors
/topics/customers.htm
www.hse.gov.uk