What is the classification given to a 5% degradation in water supply during a main drain test on an automatic wet standpipe?

A 5% degradation in water supply during a main drain test on an automatic wet standpipe is classified as an impairment. This classification indicates that while the system is still operational, there is a significant reduction in water supply performance compared to the established criteria, which could potentially affect the system's ability to respond effectively during an emergency.

Impairment is used to denote scenarios where a system's performance is compromised but not completely non-functional. It’s essential to differentiate this from terms like deficiency or failure. A deficiency typically refers to an inadequate condition that may not reach the threshold for impairment, while failure would imply the total inability of the system to perform. A warning could suggest a potential issue requiring attention but not necessarily indicate a degradation in operational capacity. Thus, identifying a 5% degradation as an impairment accurately captures the reduced efficiency while still recognizing the system remains functional.