Smoke detectors and hallways

[GG]

Does a hallway that is 4' or 40' get 1 smoke detector regardless of the length of the hallway? Someone is telling me that a "long" hallway gets 2 smoke detectors.

 

[LarryFine]

Generally, there must be a smoke between any bedroom door and the "rest" of the house. One detector can serve several rooms.

It really depends on the shape of the hall, where each door is, and where the pathway from the rest of the house enters the hallway.

 

[goldstar]

A lot depends on the specific installation and/or the manufacturer's recommendation. One of the recommendations that Firex has listed in their user's guide is

Put smoke alarms at both ends of a bedroom hallway or large room if the hallway or room is more than 30'(9.1m) long

I couldn't find anything in their literature regarding how much the square foot coverage is per detector but (many years ago) when I worked for Pyrotronics the basic coverage was 625 sq. ft (25' x 25' room) per detector. That may have changed since then.

 

[nhfire77]

"Put smoke alarms at both ends of a bedroom hallway or large room if the hallway or room is more than 30'(9.1m) long "

This is a good idea, specifically smoke detector (not alarms) standard smooth ceiling spacing is every 30 feet and within 15 feet of any wall.

So, if the hall is 30' or less long and 30' or less wide (900 sq ft) one will do.

Any bigger you would need two.

Smoke alarms use very similar detector systems and the exact same principles (photo/ion).

My 2 Cents.

 

[Dennis Alwon]

Just to clarify a 30' hall must have the smoke detector in the dead center. As stated the smokes generally have a 15' spread but you do need to check the specs as this is not a NEC issue.

 

[Split Bolt]

I was told by an inspector to add one once at the other end of a hallway. You can't have too many IMHO!

 

[Pierre C Belarge]

NFPA and the installation instructions are where you will find your answer(s).

GENERALLY speaking, the average smoke alarm will cover 30ft.

Here is one companies instructions and advice:
http://www.kidde.com/utcfs/ws-384/Assets/1275H_440381en.pdf


here is some general info:
http://www.firesafehome.org/smoke-alarm-facts/



Lets not forget that NFPA is more specific in the location of household smoke alarm locations. Most jurisdictions reference this document in their building codes, which provides additional locations not directly found in the verbage of the building codes.
For instance, it is referenced in the NYS Residential Code, and Fire Code.
My experience is that the buiding officials are getting better training and starting to understand the additional language better than in the past.

 

[CopperTone]

in massachusetts, you have to have a CO detector within 10 ft of a bedroom and a smoke outside of every bedroom, since we use combo smoke/co's - we sometimes use 2 in a long hallway especially because there usually are bedrooms at each end of the hallway. You also need a smoke at the top of the stairs - so do you need 3 in some cases? only in a large house - but we have done that before to satisfy the requirements - sounds kind of silly to have so many - but - last year a 6000 sq ft house we wired caught on fire in the middle of the night (it was not the wiring that caused the fire) the smokes went off and saved the family.

 

[Pierre C Belarge]

some more links

http://www.firstalert.com/detectors/battery


http://www.brkelectronics.com/

 

[electricmanscott]

Just to clarify a 30' hall must have the smoke detector in the dead center. As stated the smokes generally have a 15' spread but you do need to check the specs as this is not a NEC issue.

Just to clarify even more, check your local rules.

 

[Dennis Alwon]

You got it easy in Ma. In NC one in every bedroom and outside each bedroom hall area. We also need one on every floor whether there is a bedroom or not. If there are permanent stairs (not pull down) to an attic then one is required up there even if it isn't finished. of course they are all interconnected.

 

[electricmanscott]

You got it easy in Ma. In NC one in every bedroom and outside each bedroom hall area. We also need one on every floor whether there is a bedroom or not. If there are permanent stairs (not pull down) to an attic then one is required up there even if it isn't finished. of course they are all interconnected.

More or less the same here. coppertone didn't post the rules verbatim.

 

[GG]

As usual you guys are on top of your game. Thanks for the help. Im always impressed how proffesional the attitude is here on this forum. Other forums, especially the HVAC ones, are light years removed from how this forums users interact. Always a pleasure comming here and asking a question.

 

[Dennis Alwon]

I'm always impressed how professional the attitude is here on this forum.

I must admit we have the mods to thank for keeping this forum civil. Thank you.

 

[Pierre C Belarge]

in massachusetts, you have to have a CO detector within 10 ft of a bedroom and a smoke outside of every bedroom, since we use combo smoke/co's - we sometimes use 2 in a long hallway especially because there usually are bedrooms at each end of the hallway. You also need a smoke at the top of the stairs - so do you need 3 in some cases? only in a large house - but we have done that before to satisfy the requirements - sounds kind of silly to have so many - but - last year a 6000 sq ft house we wired caught on fire in the middle of the night (it was not the wiring that caused the fire) the smokes went off and saved the family.

Wording such as above can lead to confusion. I would like to see the actual wording of the requirements you are paraphrasing, I think that having one located at the "top of the stairs" is too general a statement. (I could be wrong, but I would still like to see the actual wording)


Just for FYI, in NYS the CO requirements are dramatically changed.
I am having some difficulty downloading the April 22 Emergency Bulletin for Amand's Law. I will get it and download it.

some general rules in the April 22nd changes: (the following list is in MY wording, not the actual wording)
1. installed in every sleeping room
2. interconnected
3. different sounding than the smoke alarms
4. only required if there is a combustible source in the dwelling (such as fireplace, gas appliances, etc..)
5. there are also prohibited locations.

 

[Pierre C Belarge]

One other train of thought while I am thinking about this topic.
Remember, I am speaking of my knowledge based on NYS codes!


In the larger homes today (maybe yesterday...), there may be the need to install more than 12 smoke alarms. If so, most, if not all manufacturers have a limit of 12 units interconnected. So, if there are more than 12 required there will be alternate methods required.

 

[electricmanscott]

Here is an overview of the Mass codes for new construction. Existing home codes vary by date of construction.

http://www.firepreventionofma.org/sitebuildercontent/sitebuilderfiles/fpam_new_bld_code.pdf

 

[RICK NAPIER]

2010 and earlier versions of the NFPA 72 National Fire Alarm Code 29.8.3.4(2) specifically forbids smoke detectors in unfinished attics or garages where temperatures can exceed 100*F or drop below 40*F. In NJ we would fail you for putting a smoke detector in an unfinished attic. We also require CO detectors outside the bedrooms if there are gas or oil appliances or an attached garage.

 

[cpal]

You got it easy in Ma. In NC one in every bedroom and outside each bedroom hall area. We also need one on every floor whether there is a bedroom or not. If there are permanent stairs (not pull down) to an attic then one is required up there even if it isn't finished. of course they are all interconnected.

How does a smoke in the attic work out with the Mfg listing????

 

[RICK NAPIER]

cpal

Senior Member



How does a smoke in the attic work out with the Mfg listing????
__________________
Charlie

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It doesn't