Lectures
Hierarchy of control: the order in which controls should be considered when selecting methods of
reducing a risk.
Hazard: anything which may cause harm, injury or ill health to a person
Risk: the possibility of an unwanted event occurring
Control: the measures we take to reduce the risk at an acceptable level
Risk management: describes the total procedure associated with identifying a hazard, assessing the
risk, putting in place control measures, and reviewing the outcomes
Likelihood: the chance of an event actually occurring
Accident theories
-Single factor theories
This theory assumes that an accident is the result of a single cause. If the cause can be identified and
eliminated then the accident will not be repeated.
Example: A person in a hurry, walks through a poorly lit area and trips over a piece of wood The
theory solution: remove the offending piece of wood to solve the problem Reality is that accidents
always have more than one contributing factor.
-Energy theory
The theory states that accidents are more likely to happen at or during a transfer of energy. The rate
of energy release is important because the greater the rate of release, the greater the potential for
damage.
-Multiple factor theory
The theory says that an accident occurs when a number of factors act together to cause an accident.
Example: A person in a hurry, walks through a poorly lit area and trips over a piece of wood The
theory solution: to effect a solution the multiple factor theory would require answers to the
following questions:
- Was there a necessity for that person to walk in that area or was there a safer route?
- If the person was not in a hurry would they have been more aware of their surroundings and
avoided the wood?
- If the area was better lit would the person have avoided the wood?
- Could the wood have been removed?
-Domino effect
The theory states that the events, which lead to an injury, are like 5 dominos standing on end, ready
to knock each other over in turn. The dominos are:
1) Social environment: those conditions which make us take or accept risks
2) Undesirable human traits: anger, carelessness, tiredness, lack of understanding, inattention
3) Unsafe acts or conditions: poor planning, unsafe equipment, hazardous environment
4) The accident: the accident occurs when the above events conspire to cause something to go
wrong
5) The injury: injury occurs when the person sustains damage
Often accidents occur without injury and are called ‘near misses’, when the last domino is ‘knocked
over’ the injury occurs.
The absence of accidents does not necessarily mean there are no hazards. A risk management
process must be adopted and repeated at regular intervals.
Hierarchy of control: the order in which controls should be considered when selecting methods of
reducing a risk.
Hazard: anything which may cause harm, injury or ill health to a person
Risk: the possibility of an unwanted event occurring
Control: the measures we take to reduce the risk at an acceptable level
Risk management: describes the total procedure associated with identifying a hazard, assessing the
risk, putting in place control measures, and reviewing the outcomes
Likelihood: the chance of an event actually occurring
Accident theories
-Single factor theories
This theory assumes that an accident is the result of a single cause. If the cause can be identified and
eliminated then the accident will not be repeated.
Example: A person in a hurry, walks through a poorly lit area and trips over a piece of wood The
theory solution: remove the offending piece of wood to solve the problem Reality is that accidents
always have more than one contributing factor.
-Energy theory
The theory states that accidents are more likely to happen at or during a transfer of energy. The rate
of energy release is important because the greater the rate of release, the greater the potential for
damage.
-Multiple factor theory
The theory says that an accident occurs when a number of factors act together to cause an accident.
Example: A person in a hurry, walks through a poorly lit area and trips over a piece of wood The
theory solution: to effect a solution the multiple factor theory would require answers to the
following questions:
- Was there a necessity for that person to walk in that area or was there a safer route?
- If the person was not in a hurry would they have been more aware of their surroundings and
avoided the wood?
- If the area was better lit would the person have avoided the wood?
- Could the wood have been removed?
-Domino effect
The theory states that the events, which lead to an injury, are like 5 dominos standing on end, ready
to knock each other over in turn. The dominos are:
1) Social environment: those conditions which make us take or accept risks
2) Undesirable human traits: anger, carelessness, tiredness, lack of understanding, inattention
3) Unsafe acts or conditions: poor planning, unsafe equipment, hazardous environment
4) The accident: the accident occurs when the above events conspire to cause something to go
wrong
5) The injury: injury occurs when the person sustains damage
Often accidents occur without injury and are called ‘near misses’, when the last domino is ‘knocked
over’ the injury occurs.
The absence of accidents does not necessarily mean there are no hazards. A risk management
process must be adopted and repeated at regular intervals.
