scope:

General

Humans have a limited capacity to store information in short-term and working memory. Research suggests that humans can process in short-term or working memory about five to nine pieces of information at one time.

Working memory is that memory involved in directed conscious attention. For example, start-up operating instructions for the manual operation of a potable water system requires the operator to remember pumps, chemical levels, etc. For this reason, the maritime and other industries should not rely exclusively on an individual's memory to perform work-related tasks, especially those that are complex, hazardous, and have the potential to impact personnel safety, equipment, or the environment. Appropriately written and implemented instructional materials (procedures and technical manuals) can reduce the cognitive effort of personnel, especially the memory element of performing a task, thus aiding in reducing human errors.