Which color is typically used to mark emergency shutdown equipment in ANSI standards?

The color red is designated for marking emergency shutdown equipment according to ANSI (American National Standards Institute) standards. This choice aligns with the universally recognized implications of the color red, which signifies danger, emergency, or immediate action required. In the context of emergency systems, using red helps to ensure that firefighters and other emergency responders can quickly identify critical equipment that needs to be accessed or activated in the event of a hazardous situation. This color coding aids in enhancing safety and response efficiency during emergencies.

In contrast, other colors have different standard meanings. For instance, green is often used to indicate safety or non-hazardous conditions, yellow is associated with caution and potential hazards, and blue indicates information or mandatory action. Hence, these other colors would not be appropriate for marking emergency shutdown equipment.