Bow Tie and Swiss Cheese Flashcards
What is bow tie analysis
it is diagrammatically repesents a hazardous event to show the connections between the hazards/threats and their consequences.
What do barriers and recovery represent
these activities provide controls measures
Define a hazard
potential source of harm to people, assets, the environment and company reputation
Define Top Event
incident that occurs when a hazard is realised
Define threats
what could cause the top event?
Define Barrier
what directly prevents or reduces the likelihood or a threat?
Define recovery measure
what prevents, minimizes or helps recovery from the consequence?
Define escalation factor
What could prevent the barrier or recovery measure from working as intended
Define escalation factor control
what prevent or minimises the chance of barriers or recovery measures becoming ineffective?
What can bow tie analysis be used to identify
usually the developed for only for major hazards defined under the risk assessment matrix.
What are some of the major hazards
Mining
Hydrocarbons
Toxic Materials
Air/Marine/land transport
Shipping Activities
Object under load (structure)
Lifting operations
What are the types of major hazard barriers
preventative and recovery
What are example of preventative barriers
Structures
Hydrocarbon containment
Chemical injection systems
Relief systems
What are examples of recovery barriers
Fire, gas & smoke detectors
Ignition control
Active & Passive fire protection systems
Firewater pumps & ringmain
Emergency response equipment
Emergency communication & power
Escape, Evacuation and rescue provisions
Life/survival equipment
What are is a system that is both recovery and preventative
shutdown systems
what are the types of approaches that are involved in accident investigation
System Approach
Person Approach
what is the system approach
defences, barriers and safeguards
what is the person approach
procedure and administrative control
What is the swiss cheese model
it is where the holes are presented in layers of defence, barriers and safeguards. Where the holes are due to active failures and the holes line up.
What are unsafe acts
errors and violations
What are the preconditions for unsafe acts
*substandard conditions of operation
*substandard practices of operators
what are the categories of unsafe supervision
Unforseen and known
what are the organisational influences
*resource management
*organisational climate
*operational process
What are the layers that failures can be present
*organisational factors
*unsafe supervision
*preconditions for unsafe acts
*unsafe acts
