Indicator lights are often vital to safe and efficient operation of human/machine systems. Inconsistent  and non-intuitive use of color, behavior, placement, and labeling of status indicators increases the probability of human error in quickly and accurately interpreting the operational status of a component or system. These errors can be enormously costly: losses of sales to an e-commerce site in excess $1M per minute are easily possible if a server is brought down because of a simple error like removing the wrong hard drive. And they can be extremely dangerous: an operating room patient monitoring system that has a misinterpreted warning light can put a patient at considerable risk.

ANSI/VITA 40-2003 (AV40) was created to provide intuitive and consistent status indicator implementations based on existing human factors and ergonomic standards, guidelines, and engineering "best practices". It was developed and approved as an official American National Standards Institute (ANSI) standard through the ANSI-accredited VMEbus International Trade Association (VITA) Standards Organization (VSO) in 2003. Copies of the full standard may be ordered directly from VSO at https://www.vita.com/online-store.html   Where conflicts existed among different standards and guidelines, every effort was made to choose the most universally accepted practice. In some cases, usability research was conducted to validate aspects of the ANSI/VITA 40-2003 standard.

This website is all about AV40 and its current review and update process.