Question 1 · Law, Ethics & Human Factors · Moderate
On a long inter-hospital transfer, the ventilator's low-pressure alarm has sounded several times because of road vibration, each time with the circuit intact. When it sounds again the paramedic hears it and, believing from those earlier alarms that the circuit is intact, silences it; this time the circuit has disconnected. Using the HSE classification of human failure, how is this failure best described?
- AA slip: a familiar action performed on the wrong object
- BA lapse: a required step forgotten through memory failure
- CA rule-based mistake: a remembered rule wrongly applied
- DA knowledge-based mistake: no rule known, first principles
- EA routine violation: a known rule broken as the local norm
Show answer
Answer: C
A rule-based mistake: a remembered rule wrongly applied
HSE divides human failure into errors, which are unintended, and violations, which are deliberate deviations from a rule or procedure. The paramedic did not intend to leave a disconnected circuit, and he acted on a conscious judgement rather than breaking a rule he knew applied, so this is not a violation. Nor is it a slip or lapse: those are skill-based 'actions that were not as planned' during a familiar task (the wrong switch, a forgotten step). Here the action was carried out exactly as intended but the intention was wrong — a mistake, 'where we do the wrong thing believing it to be right'. It is rule-based because he applied a rule learned from experience (these alarms are spurious), and HSE's own aide-memoire gives almost exactly this example: ignoring an alarm in a real emergency after a history of spurious alarms. A knowledge-based mistake arises when no rule is available and the person reasons from first principles. HSE's suggested controls for mistakes include planning for abnormal and emergency scenarios, regular drills, clear displays and system feedback, and decision aids.
Where this comes from
- HSE — Managing human failures: overviewHealth and Safety Executive·Types of human failure: mistakes“where we do the wrong thing believing it to be right”Open at this section
- HSE — Human failure types (aide-memoire)Health and Safety Executive·Rule-based mistake“mis-application of a good rule or application of a bad rule”Open PDF at page 2
- HSE — Human failure types (aide-memoire)Health and Safety Executive·Rule-based mistake: examples“ignore alarm in real emergency, following history of spurious alarms”Open PDF at page 2
- HSE — Managing human failures: overviewHealth and Safety Executive·Types of human failure: violations“A violation is a deliberate deviation from a rule or procedure”Open at this section