Smoke Detector Spacing for High Ceiling Spaces

Fire Protection Research Foundation report: “Smoke Detector Spacing for High Ceiling Spaces - Phase II"
Author: Mishuk Datta, PE, Jensen Hughes
Date of issue: July 2023

Report

Smoke Detector Spacing for High Ceiling Spaces - Phase II

The Research Foundation conducted a study to provide guidance for the installation of smoke detectors on ceilings over 10 ft (0.3 m). The outcomes propose prescriptive guidance for ceiling heights up to 40 ft (12 m), with equations to determine appropriate spacing based on the ceiling height for spot type and beam type detectors. Performance-based designs are encouraged for ceiling heights exceeding 40 ft (12 m).

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Previous report

Fire Protection Research Foundation report: “Smoke Detector Spacing for High Ceiling Spaces"
Author: Erik Smedberg & Enrico Ronchi, Lund University
Date of issue: October 2017

Report

Smoke Detector Spacing for High Ceiling Spaces

The Research Foundation initiated this project to review available literature and standards and perform a gap analysis related to the impact of ceiling height and detector spacing on smoke detection performance to inform the NFPA 72 Technical Committee.

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NFPA 72, National Fire Alarm and Signaling Code, does not address spacing consideration for smoke detection based on ceiling heights. However, there is a table that allows for reduction of spacing for heat detection. There has been confusion in design and code enforcement on what to do when smoke detectors are installed on higher ceilings. There is a need for clarification on how to apply smoke detection spacing requirements. To provide guidance, the Technical Committee needs additional information on the impact of ceiling height and detector spacing on smoke detection performance.

Download Executive Summary. (PDF)