Reference · Codes & Standards
Supervisory Signal
A signal that indicates something that affects the fire protection system needs attention but is not a fire — for example a closed sprinkler valve, low air pressure or a disabled duct detector. Distinct from alarm and trouble.
NFPA 72: 3.3 (definitions), 10.7, 10.15
Section numbers vary by edition — confirm in the edition your AHJ has adopted.
Read more in these guides
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