# NFPA 72 smoke detection placement



## codeworks (Sep 29, 2011)

I should have 72, however, I don't (yet). I need info on placement of smokes with repect to proximity of corners at walls or ceilings. I am seeing smokes (imho) to close to walls when ceiling mounted (closer than 12" to wall/ceiling corner). I vaquely remember something about not closer than 12" to a wall ceiling line, having to do with smoke roll, the way it curls in corners, etc. I always put them out 2 to 3 feet away from the door opening so that if there was smoke, as it worked across the ceiling  it would hit the detector early . My goal is top be as thorough and as informed as possible.  I appreciate any input.


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## mtlogcabin (Sep 29, 2011)

http://www.nfpa.org/itemDetail.asp?categoryID=1648&itemID=39907&URL=Safety Information/For consumers/Fire & safety equipment/Smoke alarms/Installation and maintenance tips

http://www.nfpa.org/assets/files/PDF/Public%20Education/AlarmInstallGuide.pdf


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## AegisFPE (Sep 29, 2011)

Generally the accepted minimum is 4 inches (2007 NFPA 72-5.7.3.2.1).


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## cda (Sep 29, 2011)

you can also read the installation instructions that come with the detector and normally shows a picture


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## FM William Burns (Sep 29, 2011)

From NFPA 72 Chapter on Household ………………….







> A.29.8.3 One of the most critical factors of any fire alarm system is the location of the fire detecting devices. This annex is not a technical study. It is an attempt to provide some fundamentals on fire-warning equipment location. For simplicity, only those types of alarms or detectors recognized by Chapter 29 (e.g., smoke and heat alarms or smoke and heat detectors) are discussed. Specific mounting locations of fire-warning equipment in unoccupied or architecturally unique areas (e.g., as in attics or in rooms with high ceilings) should be evaluated by a qualified professional.





> The conclusions of the Kemano Study and FPRF Smoke Detector Spacing Requirements Report (2008) have determined revisions to smoke alarm and smoke detector mounting within 4 in. (100 mm) of a flat ceiling/wall corner are now acceptable. The studies have shown that acceptable detection performance does not depend on the 4 in. (100 mm) separation. Figure A.29.8.3 illustrates acceptable smoke alarm and smoke detector mounting locations.






> A.29.8.3.3 Figure A.29.8.3 illustrates acceptable smoke alarm or smoke detector mounting locations. In those dwelling units employing radiant heating in the ceiling, the wall location is the recommended location. Radiant heating in the ceiling can create a hot air boundary layer along the ceiling surface, which can seriously restrict the movement of smoke and heat to a ceiling-mounted detector.









By arsnman4 at 2011-10-01

Another bad location is the interior ceiling area adjacent to the door header.


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