What type of tag should be placed on the main control valve when systems are partially or fully out of service?

A red tag is used to indicate that a system is partially or fully out of service, alerting personnel that there are restrictions regarding the operation of the sprinkler system. The inclusion of a red tag serves as a crucial safety measure, ensuring that anyone who approaches the main control valve understands the system is not in full working order. This helps to prevent accidental activation or unnecessary work on a system that should not be engaged due to known issues.

In the context of sprinkler systems, maintaining clear communication about the operational status is vital for safety and maintenance purposes. Such tagging systems are often used in various trades to standardize the method of conveying essential operational information.