MAP-01-011 HFI Technical Guide - Human Factors Integration ...

Annex 3 – HF Techniques, Methods and Tools• Disadvantages• The TRACEr technique appears unnecessarily over-complicated for what itactually is, a taxonomy based error analysis tool. A prototype studyhighlighted a number of areas of confusion in participant use of thedifferent categories.• No validation evidence or studies using TRACEr.• For complex tasks, analysis will become laborious and large.• Very high resource usage (time). In a participant questionnaire used inthe prototype study (No citation reference - Shorrock 1997) resource usage(time and expertise) was the most commonly reported area of concern(DTC089 - Isaac, Shorrock and Kirwan 2002).• Training time would be extremely high for such a technique.• Extra work involved if HTA not already available• Existing techniques using similar EEM taxonomies appear to be far simplerand much quicker (SHERPA, HET etc).A3.10.7SPEARThe System for Predictive Error Analysis (SPEAR) is a systematic approach toHEI that is very similar to other systematic HEI techniques, such as SHERPA.The main difference between SPEAR and SHERPA is that the SPEAR techniqueutilises performance-shaping factors (PSF) in order to identify any environmentalor situational factors that may enhance the possibility of error. The SPEARtechnique itself operates on the bottom level tasks (operations) of a HTA of thetask under analysis. Using subjective judgement, the analyst uses the SPEARhuman error taxonomy to classify each task step into a particular behaviour types(Action, Retrieval, Check, Selection or Transmission).Each behaviour has an associated set of EEMs, such as action incomplete,action omitted and right action on wrong object. The analyst then uses thetaxonomy and domain expertise to determine any credible error modes for thetask in question. For each credible error (i.e. those judged by the analyst to bepossible) the analyst should give a description of the form that the error wouldtake, such as, ‘pilot dials in wrong airspeed’. Following this the analyst has todetermine how the operator can recover the error and also any consequencesassociated with the error. Finally, error reduction measures are proposed, underthe categories of procedures, training and equipment.• Advantages• SPEAR provides a structured approach to HEI.• Simple to learn and use.• Unlike SHERPA, SPEAR also considers PSF’s.May 2006 Page A3-95 Issue 4