Light vehicle fuelling errors in the UK: the nature of the problem, its consequences and prevention.

Errors arising during the fuelling of light vehicles are increasing. It is estimated that around 300,000 misfuellings occurred in the UK in 2001 alone, with direct costs of approximately pound35 million and considerable inconvenience caused to all those involved. This study has investigated the causes of fuelling errors. A hierarchical task analysis of the fuelling of light vehicles was developed and data gathered from 23 individuals who had misfuelled. Errors were found to have occurred because the physical and psychological conditions on the filling station forecourt presented sufficient opportunity for an error producing sequence of events to be triggered. These occurred when specific factors were present either singly or in combination in the fuelling environment, creating an error 'pathway'. The probability of an error occurring is dependent upon the strength and type of influence these factors have on the performance of the fuelling task. It is proposed that errors are best prevented by applying ergonomic principles to the design, and/or modification of filling station layout and equipment. In this way, the error pathways may be broken and successful fuelling encouraged.