Risk Management Flashcards
What is permit to work?
Management systems e.g. entry permit, hot work permit, maintenance permit, electrical isolation permit, isolation permit, roof access permit, excavation permit
What are the three steps for risk assessment?
• Three steps to risk assessment:
1) How big is the problem
2) How often will it occur
3) So what to do about it?
What are the three main consequence models?
Main consequence models: fire, explosion and gas dispersion
Explain the consequence models
Gas Dispersion- The main types of dispersion are:
• Jets - release at high exit velocity.
• Puff - the sudden release of a neutrally buoyant gas.
• Passive - the release at low exit velocity.
• Heavy Gas Dispersion - the dispersion of a sudden release of a heavy (denser than air) gas.
Fire-The main types of fire are:
1. Torch (Jet) release of fluids at high velocity.
2. Pool the spread is defined by bunds, drains or the rate of release and rate of combustion.
3. Vapour Explosion (BLEVE) Fireball - the rupture of a vessel in a fire and the sudden release of massive
quantities of fuel.
4. Flash Fire the low pancake like fire lasting only a few seconds.
Explosion: The main types of explosion are either confined - a pump room or analyses house or even a compressor house or unconfined - an open plant or structure.
What is used to assess event frequency?
1 Experience - Your experience may show that an average pumps have to be overhauled once every three years but this may not be the experience of someone else. Experienced as with data requires to be analyses very carefully as to the relevance.
2 Fault Trees- They normally start at the end point (such as an explosion) and start to define the exact combination of events that are required to create this event
3 Event Outcome Trees
Are a variation on fault trees and use a “yes/no” probability logic to define the event flow using data as derived above. The starting point is given such as a leak every 100 years.
Define risk assessment
The quantitative evaluation of the likelihood of undesired events and the likelihood of harm or damage being caused, together with the value judgements made concerning the significance of the results.
