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

MAP-01-011 – HFI Technical Guide (STGP 11)resolved by the need to respect relevant Legislation or safety-case principles thatlimit human involvement in hazardous tasks. Similarly, the overall system safetycase may call for levels of system accuracy and reliability that preclude humanexecution of a function.In many other cases, appropriate AoF may be based as much on overall cost ofownership metrics and issues of feasibility associated with existing operationaland management structures as on pure technical and sociological factors.Sound knowledge of the customer’s operational and managerial environment istherefore an essential component to the AoF process.AoF typically occurs during the Assessment and Demonstration phases of aproject. It requires a multi-disciplinary approach with access to appropriateSMEs. Valid human performance source data are required, as are skilledanalysts, together with input from Human Factors professionals. AoF maytherefore be very resource demanding.• Advantages• Analysis of functions allows the designers to ensure that the tasks arecarried out by the most efficient system component.• The AoF provides a structure to the automation decision process and alsoensures that automation decisions are traceable.• Provided that the appropriate personnel are used, the procedure is asimple and straightforward one.• Disadvantages• The process is time consuming and involves a great deal of work (e.g.HTA, stakeholder analysis, allocation of functions etc).• A multi-disciplinary team of HF specialists, potential end-users, anddesigners are required in order to conduct the analysis properly. It may bedifficult to assemble such a team.A3.3.3Mission AnalysisMission Analysis considers a comprehensive set of defined operational missionprofiles. A sub-set of profiles is selected to encompass the critical or limitingdemands on the system. Each mission profile is divided into a number of phasesand related operating modes. Each mode is then divided into task steps, whichare then categorized in terms of frequency, criticality, demands, etc. For eachidentified task the associated system functions are identified. Essentially, thisconstitutes the allocation of the task to the machine component, the humancomponent or a sharing of the function between the two (Otherwise calledAllocation of Functions, Sect A3.3.2). For each task, the necessary informationand control affordances (i.e. cues to functionality) are then identified. MissionAnalysis is simple to apply, but depends crucially on the selection of appropriatescenarios. It may be resource demanding.May 2006 Page A3-20 Issue 4