5.1 What Is Task Analysis?

A task analysis is any process for assessing what a user does (task), how the task is organized, and why it is done in a particular way and using this information to design a new system or analyze an existing system. Task analysis is an investigative process of the interaction of operators and the equipment and/or machines they utilize. It is the process of assessing and evaluating all observable tasks and then breaking those tasks into functional units. These units allow for the evaluators to develop design elements and appropriate training procedures and identify potential hazards and risks.

Task analysis has been defined as “the study of what an operator (or team of operators) is required to do, in terms of actions and/or cognitive processes, to achieve a system goal” (1). Approaches to task analysis have been classified into three categories: normative, descriptive, and formative. According to Vicente (2), normative approaches “prescribe how a system should behave,” descriptive approaches “describe how a system actually works in practice,” and formative (also called predictive) approaches “specify the requirements that must be satisfied so that the system could behave in a new, desired way.” The nature of the work domain and the task influence the type of analysis that is appropriate. Both the normative and descriptive approaches are applicable to analyze existing systems, while the formative approach can be applied to develop and design a new system that will support work that has not been previously done or to allow the work to be done in a new way. The normative approach is appropriate for a very mechanical and predictable work environment; as the work becomes more complex and unpredictable, requiring more judgment, then the formative approach becomes a better analysis tool (3).