26
Sensemaking in Safety Critical and Complex Situations
to unforeseen circumstances, and situational violations are due to situation-specific
factors ( e.g. excessive time pressure).
The writer was once asked during a safety presentation what to do if employees
do not follow standard operating procedures and replied that the first thing to do was
to determine what was wrong with the procedures.
Risk Homeostasis Theory ( RHT): Wilde ( 1994) developed RHT during research
into road safety. Although RHT is controversial, it may provide insights into the factors that promote rule following and rule breaking. Many, seemingly effective, safety
interventions may provide perverse incentives for risk taking that were not considered
when the intervention was introduced. RHT starts with the proposition that in any
situation where people have control over a process, they adjust their behaviour in relation to a ‘ target level of risk’ which is assessed using feedback from the task. Drivers,
for example, may drive faster on wider roads and slow down when it starts to snow,
the target level of risk is set by the perceived costs and benefits of engaging in safe or
unsafe behaviour. For example, when driving to a business meeting, motorists may
drive faster if they left home too late rather than too early. For safety investigations
where a violation has occurred, RHT prompts the investigator to search for PSFs that
might have prompted the violation ( e.g. excessive time pressure, management rewards
productivity but not safety). What appear from the outside to be violations may to
operators be nothing more than normal behaviour within their ‘ comfort zone’.
From the perspective of safety management, accidents often happen when people
think they are safe. The following needs to be considered: design systems so that
operators have an accurate perception of the true risk of accidents as well as the
consequences; when designing safety procedures, consider the costs and benefits to
operators of following safety procedures; and, if necessary, provide explicit rewards
for safety behaviour and not only penalties for unsafe behaviour.
TIME PRESSURE – AN IMPORTANT ISSUE FOR HUMAN FACTORS
Failure to follow standard operating procedures or deliberate violation of such procedures may be a symptom of deeper trouble in the organisation rather than merely
negligence or fatigue on the part of the operators. The official report into the grounding of the Herald of Free Enterprise found that the failure to close the bow doors
of the vessel before it sailed had happened before on other ferries owned by the
company. Evidence that Masters were under pressure to leave Zeebrugge 15 minutes
early was cited in the official report ( Department of Transport 1987):
The sense of urgency to sail at the earliest possible moment was exemplified by an
internal memorandum sent to assistant managers by Mr. D. Shipley, who was the operations manager at Zeebrugge. It is dated 18th August 1986 and the relevant parts of it
reads as follows: ‘ There seems to be a general tendency of satisfaction if the ship has
sailed two or three minutes early. Where, a full load is present, then every effort has
to be made to sail the ship 15 minutes earlier …. I expect to read from now onwards,
especially where FE8 is concerned, that the ship left 15 minutes early … put pressure
on the first officer if you don’t think he is moving fast enough. Have your load ready
when the vessel is in and marshal1 your staff and machines to work efficiently. Let’s put
the record straight, sailing late out of Zeebrugge isn’t on. It’s 15 minutes early for us’.
On the day of the accident, the ferry’s departure was 5 minutes late.
Sensemaking in Safety Critical and Complex Situations
to unforeseen circumstances, and situational violations are due to situation-specific
factors ( e.g. excessive time pressure).
The writer was once asked during a safety presentation what to do if employees
do not follow standard operating procedures and replied that the first thing to do was
to determine what was wrong with the procedures.
Risk Homeostasis Theory ( RHT): Wilde ( 1994) developed RHT during research
into road safety. Although RHT is controversial, it may provide insights into the factors that promote rule following and rule breaking. Many, seemingly effective, safety
interventions may provide perverse incentives for risk taking that were not considered
when the intervention was introduced. RHT starts with the proposition that in any
situation where people have control over a process, they adjust their behaviour in relation to a ‘ target level of risk’ which is assessed using feedback from the task. Drivers,
for example, may drive faster on wider roads and slow down when it starts to snow,
the target level of risk is set by the perceived costs and benefits of engaging in safe or
unsafe behaviour. For example, when driving to a business meeting, motorists may
drive faster if they left home too late rather than too early. For safety investigations
where a violation has occurred, RHT prompts the investigator to search for PSFs that
might have prompted the violation ( e.g. excessive time pressure, management rewards
productivity but not safety). What appear from the outside to be violations may to
operators be nothing more than normal behaviour within their ‘ comfort zone’.
From the perspective of safety management, accidents often happen when people
think they are safe. The following needs to be considered: design systems so that
operators have an accurate perception of the true risk of accidents as well as the
consequences; when designing safety procedures, consider the costs and benefits to
operators of following safety procedures; and, if necessary, provide explicit rewards
for safety behaviour and not only penalties for unsafe behaviour.
TIME PRESSURE – AN IMPORTANT ISSUE FOR HUMAN FACTORS
Failure to follow standard operating procedures or deliberate violation of such procedures may be a symptom of deeper trouble in the organisation rather than merely
negligence or fatigue on the part of the operators. The official report into the grounding of the Herald of Free Enterprise found that the failure to close the bow doors
of the vessel before it sailed had happened before on other ferries owned by the
company. Evidence that Masters were under pressure to leave Zeebrugge 15 minutes
early was cited in the official report ( Department of Transport 1987):
The sense of urgency to sail at the earliest possible moment was exemplified by an
internal memorandum sent to assistant managers by Mr. D. Shipley, who was the operations manager at Zeebrugge. It is dated 18th August 1986 and the relevant parts of it
reads as follows: ‘ There seems to be a general tendency of satisfaction if the ship has
sailed two or three minutes early. Where, a full load is present, then every effort has
to be made to sail the ship 15 minutes earlier …. I expect to read from now onwards,
especially where FE8 is concerned, that the ship left 15 minutes early … put pressure
on the first officer if you don’t think he is moving fast enough. Have your load ready
when the vessel is in and marshal1 your staff and machines to work efficiently. Let’s put
the record straight, sailing late out of Zeebrugge isn’t on. It’s 15 minutes early for us’.
On the day of the accident, the ferry’s departure was 5 minutes late.