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NFPA 72 Smoke Detection and Alarm Systems

Updated Apr 3, 2026

Establishes smoke detector types, locations, and interconnection requirements.

NFPA 72 Chapter 17 addresses smoke detection. Photoelectric detectors respond to visible smoke and work well for smoldering fires. Ionization detectors respond to invisible combustion particles and work well for flaming fires. Dual-sensor detectors combine both technologies. Residential smoke detectors must be interconnected so activation of one detector triggers alarms throughout the dwelling. Battery-backup ensures operation during power loss. Detectors must be ceiling-mounted at least 4 inches from walls (side-wall mounting reduced effectiveness).

TAGS

nfpa smoke-detection alarms

DETAILS

section

17

category

Fire Alarm Systems

code body

NFPA

code year

2022

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