Which factors and situations for human functional failures? Developing grids for accident causation analysis

Abstract

This report describes the work undertaken in Task 5.2 of the TRACE project. Human failures are
\nexplained by factors characterizing the state of the system and of their interactions. A grid of factors
\nwhich could lead to these human functional failures is given along with a grid of pre-accident driving
\nsituations. In addition to this, an overview is included of the background work undertaken to
\nestablish a methodology for classification of these factors and situations. Factors related to the ‘User’,
\n‘Vehicle’ and ‘Environment’ are described and classifications for use at a ‘descriptive’, ‘generic’ and
\n‘in-depth’ level are determined, to allow analysis at different levels of detail of accident data. These
\nfactors and situations will be used along with the Task 5.1 functional failures to help identify typical
\nfailure generating scenarios in Task 5.3, and the subsequent analysis of real world accident data in
\nother work packages in TRACE. They will also be a useful basis for future improvements in the
\ncollection of accident causation data, avoiding the common over simplification whereby road users
\nare seen as the main reason for the ‘failure’ in the accident scenario.