Investigating Incidents - The Human Factors Perspective

HSL ergonomists and human factors specialists have contributed to many accident investigations, ranging from serious injuries to multiple fatalities. Typically, we consider three main factors:

• Job - the task, workload, the working environment, design of displays and controls and procedures. Mental aspects include the perceptual, attentional and decision making requirements.
• Individual - competence, skills, attitudes, risk perception.
• Organisational - work patterns, workplace culture, resources, communications, leadership.

Case Study 1: Investigation of the Ladbrook Grove Rail Crash
As part of our contribution to HSE's investigations of this incident we considered:

• Job - Signal sighting problems, time available to observe the signal, conflicting demands of the driving task;
• Individual - competence and experience, including expectation relating to previous stop signals in this area;
• Organisational - working shifts, train driver training.

The difficulties experienced by passengers attempting to escape from the trains following the crash were also studied - these included safety instructions, escape routes and escape equipment (glass hammers, emergency door levers etc). Our recommendations were fed into Lord Cullen's Inquiry.

Case Study 2: Machinery Accidents
HSL assisted in the investigation of two serious incidents in the UK where workers suffered arm amputations after becoming entangled in woodchippers during normal operations. We looked at the possible circumstances leading to the accidents and how they might be prevented. We considered:

• Body size factors - reach distances;
• Working practices - observation;
• Potential accident scenarios - using computer modelling.

We suggested improvements to the design of the emergency shut-off devices to prevent these accidents. These were implemented in the UK by December 2002, and are incorporated in the draft European Standard for woodchippers.

  For further information on incident investigations please click here

Further Details
Contact our Business Development Group by telephone (+44) 01298 218218, fax (+44) 01298 218822 or email hslinfo@hsl.gov.uk.

  Back to the top