Human factors
When experts investigate an accident after the event, it is important to find out not just how it happened but probably more importantly, WHY it happened.
As you can read in the section on near-misses, 80% of accidents are directly attributable to human error. The final 20% that require closer investigation generally also turn out to be due to human error. Experts used to focus on investigating where people had made mistakes so that they could be identified and corrected. But most people nowadays agree that human error is a sign of underlying problems in systems so in investigations these days, they are more inquisitive about the significance of people's behaviour, actions and reactions in accidents depending on the circumstances at the time the accident happened.
Below we list a whole range of factors that can cause human error. Studies have shown that the same factors apply world-wide irrespective of nationality, language, culture or continent. Consider using these factors in your work on prevention and thinking how you can take preventative action for the various factors.
At the individual level
- Stress
- Fatigue
- Knowledge
- Experience
- Training and education
- Anxiety (problems/questions)
- Memory problems
- Common/general values and standards
- Common language
- Interpretation
- Decisions
- Risk assessment
- Behaviour
Group level
- Conflicts
- Local management and tasking
- Communication
- Attitudes
- Loyalties
- Ownership
Organisational level
- Contradictory objectives
- Procedures
- Training and learning strategies
- Maintenance
- Competition
- Pressure of time
- Financial pressure
- Cost consciousness
- Safety culture
- Organisational culture
- Housekeeping/Administration
- Aims and intentions
- Fault management
- Accident management
- Support and guidance
- Freedom of action
- Communication
- Change management
Society and culture
- Upbringing
- Qualifications:
- Standards
- Values
- Family relations
- How to tackle the world
Practice
- Managing conflicting objectives
- Standard operating procedures
- Short cuts
- Risk assessment
- Risky behaviour
- Traditions
- Watch system
- Contravention
- Overconfidence
- Audits
- Supervision/inspection
- Supervisors/Inspectors
Physical environment
- Light/dark
- Vibration/motion
- Slippery/wet
- Soft/hard
- Steep/flat
- Lighting
- Noise level
- Heat/cold
Technology
- Options and limitations
- Errors - tolerance
- Errors - obviousness
- Superfluity
- Reliability
- System transparency
- Passive controls
- Changes made by the crew
- User friendliness
- Level of automation
- Overconfidence
- User interface and design
- Unintended consequences
More information
If you would like to know more about human factors, here are some suggestions.
- The field guide to human error investigations by Sidney Dekker (Seahealth Denmark recommendation)
- Human factors in the maritime domain by Michelle Rita Grech, Tim John Horberry and Thomas Koester
- Investigating Human Error by Barry Strauch
- Managing risks of organizational accidents by James Reason
- Eyewitness testimony by Elisabeth F. Loftus
- Human factors in flight by Frank H Hawkins