This part of ISO 9241 defines usability and explains how to identify the information which is necessary to take into account when specifying or evaluating usability in terms of measures of user performance and satisfaction. Guidance is given on how to describe the context of use of the product (hardware, software or service) and the required measures of usability in an explicit way.
The guidance in this part of ISO 9241 can be used in procurement, design, development, evaluation, and communication of information about usability. It includes an explanation of how the usability of a product can be specified and evaluated as part of a quality system which conforms to ISO 9001. It applies both to products intended for general application and products being acquired for or being developed within a specific organisation.
This part also explains how measures of user performance and satisfaction can be used to measure how any component of a work system affects the quality of the whole work system in use.
The guidance includes procedures for measuring usability but does not detail all the activities to be undertaken. Specification of detailed user-based methods of measurement is beyond the scope of this part of ISO 9241, but further information can be found in Annex B and the bibliography in Annex E. Some other parts of ISO 9241 contain specific user performance test methods.
This part of ISO 9241 applies to office work with visual display terminals, and other situations where a user is interacting with a product to achieve goals. ISO 9241 parts 14 to 17 provide recommendations which are applicable in given contexts of use. The guidance in this part can be used in conjunction with ISO 9241 parts 14 to 17 in order to identify the applicability of individual recommendations.