Download Hazard Identification in Chemical Plants: Checklists, What-if, and FMEA and more Lecture notes Workplace Safety in PDF only on Docsity!
Here is an example of a selection of hazardous event list for a
chemical plant:
Screening Level Checklist What-if FMEA HAZOP Started Identification Human Error Analysis – Case Studies Thoughts Process Section Hazardous Event Natural Gas Supply Jet Flame Process Steam Supply Boiler Explosion Feed Gas Preparation Spent Catalyst Bed Reformer Unit Firebox Explosion Shops Building Drum Spillage Fuel Depot Gasoline Leak from Tanks Carbon Dioxide Injection System Liquid Spill Methanol Separator Gas Release and Fire Distillation Section Pool Fire Electrical Supply Pool Fire Cooling Tower Carryover Emission
STEP 5
List all major potential causes of identified hazardous events.
Use checklists to organise the causes into 5 categories:
- Open-ended loss of containment – drains, vents, relief valves, etc.
- Internal agency – disintegration of rotating machinery, blockage, etc.
- External agency – collision, weather, seismic, etc.
- Equipment failure while operating within design conditions due to
deterioration, faulty maintenance or improper replacement of materials.
- Equipment failure by exceeding design limits on pressure, temperature and
composition
Screening Level Checklist What-if FMEA HAZOP Started Identification Human Error Analysis – Case Studies Thoughts
Checklists
• A checklist is a detailed lists of known intrinsic hazards or
hazardous events compiled based on past experience facility
design and operation.
• Questions are answered with a “YES” or “NO”
• Hazards are identified through compliance with established
standards
It is essential that checklists be validated for system before use.
Screening Level Checklist What-if FMEA HAZOP Started Identification Human Error Analysis – Case Studies Thoughts
Checklists
Purpose
• Identify hazards
• Check compliance with a set of standard procedures
Reviews
• Existing systems – tours, inspections, interview
• New process – team member review of process drawings
Results
• Responses to standard checklist questions
• List of hazards and suggested corrective action
Screening Level Checklist What-if FMEA HAZOP Started Identification Human Error Analysis – Case Studies Thoughts
Advantages
• Can be used by non-
system experts
• Capture a wide range of
historical experience and
knowledge
• Ensures common or
obvious problems are not
overlooked
• Limited application to
new systems
• Inhibits creative thinking
about new hazard
identification
• Overview hazards that
have not been previously
identified
What-if FMEA
Disadvantages
Screening Level Checklist HAZOP Started Identification Human Error Analysis – Case Studies Thoughts
• The simplest process hazard analysis techniques
• Provides quick results and communicates information wells
• Good way to account for learned lessons
• NOT a good method for identifying new or unrecognised hazards
• Application requires good knowledge of the system and standard
operating procedures
• Requires regular updating and auditing
Screening Level Checklist What-if FMEA
Final details of the Checklist procedure
HAZOP
Started Identification Human Error Analysis – Case Studies Thoughts
What-if analysis
Purpose
• Identify hazards and consequence to develop risk mitigation
strategies
Requirements
• Process descriptions, drawings and operating procedure
• Preliminary list of what-if questions
Analysis Procedure
• Go through the system process, starting with the
introduction of the feed until the end of the process
• Ask “what-if” each process stage
Results
• Recommendations on the effects of removing hazards
Screening Level Checklist What-if FMEA HAZOP Started Identification Human Error Analysis – Case Studies Thoughts
