This part of ISO 9241 applies to linear detachable keyboards designed for stationary use. It provides guidance on the design of keyboards used for typical office tasks so that the limitations and capabilities of users are considered. It provides guidance based on ergonomic factors for keyboard layout arrangements, the physical characteristics of the individual keys and the overall design of the housing containing the keys. This part of ISO 9241 specifies methods for testing conformance by measuring the physical attributes of a keyboard. It also includes a proposed alternative test method for keyboards that do not conform to the physical design requirements and recommendations, based on a user performance test and subjective rating scales.