Where to position smoke / CO alarm

[leenowell]

Hi All

My boiler is in the garage and because my daughter's bedroom is above the g arage, I want to fit a carbon monoxide/ smoke alarm in the garage to ensure the boilers are ok. Challenge is that where the boiler is there is a stee l beam about 1m in from the wall with the boiler one side of it and the res t of the garage the other. The top of the boiler is a little below the leve l of the bottom of the beam.

So.... Where is best to mount the smoke/ co alarm ?

1. Directly above the boilers. Concerned here that the beam will block any smoke generated in the garage as beam hands down around 200 / 300mm
2. On the beam. Concerned here that the CO from boilers would rise and mis s the alarm

Any views?

Thanks

Lee.

[Robin]

CO neither rises nor falls to any significant extent; it diffuses throughout the room, so anywhere will do for that. See eg

[Murmansk]

Seems to me you need to put the detectors in your daughter's bedroom as a first priority as she's your main concern.

Presumably her room is configured conventionally so if you follow the guidance in the instructions you as to placement you'll have eliminated as much risk as you can.

My vague memory of smoke alarm installation is that they need to be on the ceiling and not too close to the walls as there is a kind of "dead zone" at the edges of the room near the ceiling where smoke doesn't go until the later stages of a fire.

[newshound]

I'd certainly have at least a smoke detector in there as well, they are cheap enough!

[Andrew Gabriel]

+1

People have died in their bedroom from CO which did exit the flue, but re-entered the house for some reason. I recall one case where it was a neighbour's boiler, not their own.

The place for the first smoke alarm is on the upstairs landing ceiling, near the top of the stairs where heat (smoke) rising from downstairs will trigger it (but not directly over the stairwell if this makes battery replacement difficult).

(It may be different if you have anyone in the house who smokes, particularly anyone who smokes where they might fall asleep, such as in bed or in a chair in the living room. These are extremely high fire risks.)

[Brian Gaff]

I've never been happy with both in one unit myself. I don't them need the carbon monoxide alarm as i have nothing combustible burning, but the smoke alarm needs to be above things near what you expect to catch fire, hopefully not! Its a good idea perhaps then to fit the combined one neardr the boiler and have a smoke one in other parts of the house. My smoke alarm even goes of if a mild singed bit of toast occurs iin the toaster and its mounted halfway up the stairs on the side of the ceiling/floor where you come up, making it very easy to test turn on and off and change the batteries without a step ladder. Brian

[alan_m]

And according to my Carbon Monoxide Alarm installation instructions if fitted in a bedroom fit it at breathing level which in a bedroom is at pillow height.

[alan_m]

With my CO alarm they advise not fitting it directly above the appliance but 1 to 3m horizontally away from it either on the ceiling or high up on the wall (but with a gap of around 150mm from the ceiling). In your case the instructions indicate the boiler side of the beam and as you boiler is so high up probably mounted on the ceiling. Also, not close to a door.

For a CO alarm there is a warning about using it in the vicinity of an air freshener or close to the storage of solvent based paint or thinners.

The position for a fire detector may be different.

[ARW]

I recently bought an Aico Ei208 for the first time and was so impressed with it I recommended it to this newsgroup.

For the £18 or so that they cost I would suggest fitting an extra CO detector in her bedroom.

[Martin Brown]

It doesn't much matter where you put a CO alarm in a room provided it isn't too close to the potential source of trace CO. Mine recommends that it is placed at least 2m horizontally away from the wood burning stove. It has never given a false alarm in that position.

I do move it closer by on a windy day sometimes to test it (noisy).

You can get ones which will sit on a mantlepiece with a periodic health light that flashes and LCD ppm CO display - much like a smoke alarm.

[alan_m]

Based on your recommendation I purchased one. I have been meaning to purchase a co detector for the past 12 months and your post kicked me into buying one.

The nice touch is the audio data transfer to an App on a smart phone (not a required function if you just want to use it as an alarm)

£17.50 incl postage.

(Note: Instructions on the audio link are only on the packing - start the smart phone app and press the test button 3 times)

[Martin]

Recommendations are that a CO detector should not be on the ceiling with a smoke alarm but at around head height. In the USA Nest smoke/CO detectors were criticised for being fitted at ceiling height.

[Robin]

Some may have criticised Nest but do they have any evidence to back it up?

If they did it's odd the NFPA in the USA still has:

"CO alarms should be installed in a central location outside each sleeping area and on every level of the home and in other locations where required by applicable laws, codes or standards. For the best protection, interconnect all CO alarms throughout the home. When one sounds, they all sound.

"Follow the manufacturer?s instructions for placement and mounting height."

While Nest have:

You should install your Nest Protect smoke and CO alarm on the ceiling or wall according to the directions in the User?s Guide. When installed on the ceiling, Nest Protect should be a minimum distance of 30 cm away from the wall.

[ARW]

Or online - someone had thrown the packaging:-)

Fitted one at the scout hut for a sleep over (powers that be demanded one). I could have gone mains powered by I was a bit pushed for time.

[ARW]

I was at a job (new build) when some insurance inspector came in. He commented that the CO detectors where on the ceiling and it was a pet hate of his as CO was heavier than air.

I tapped the mike on my phone and said "Is carbon monoxide heavier than air" of course the phone just read out (in front of everyone in the room)

"According to NEST there's a myth that carbon monoxide alarms should be installed lower on the wall because carbon monoxide is heavier than air. In fact, carbon monoxide is slightly lighter than air and diffuses evenly throughout the room"

He then f***ed off to find as many faults as he could.

[leenowell]

These alarms look cool. Wish I had asked before I bought the one I have. Sorry should have said.... The house has mains smoke alarms to meet current regs just doesn't have a CO alarm nor smoke alarm in the garage.

[Martin]

NEST has a vested interest. They sell a combined CO and smoke detector. the best place for a smoke detector is at ceiling height, the best place for a CO detector is at head height. At head height it measures what you are breathing.

[Martin]

If you put a CO alarm in your garage it will be triggered by your car exhaust.

[Robin]

BS EN 50292 allows wall or ceiling mounted alarms. And NEST aren't the only suppliers of ceiling mounted alarms. Eg Kidde recommend on a ceiling or on a wall at least 1.5m above the floor - which ain't the height where I'm breathing when watching TV or sleeping.

[Martin]

but a lot closer than one mounted on the ceiling.