Hierarchical Task Analysis
The Hierarchical Task Analysis (HTA) can be performed before or after the Predictive Human Error Analysis technique (PHEA). It is the process of breaking an operational or manufacturing task down into its sub and sub-sub tasks including prerequisite and timing requirements such as where tasks need to be carried out in a specific order.
The HTA technique is a well-established method for task analysis and is sometimes linked to a job safety analysis of critical procedures as a pre-cursor to human reliability assessment. The first step is to create an overall task diagram that can be developed into sub-tasks, which definitively describes the operational or manufacturing procedure required to complete a safety critical task such as replacing a filter in a hazardous process. Once identified the task can be analysed for potential human factor failure modes and quantified if necessary. Once completed the HTA/JSA should improve the overall procedure.
ProSalus use the HTA technique as a part of on-site safety critical procedure assessment.