Starting in October, CO detectors will be required in Connecticut, installed outside the bedroom area. I thought CO was heavier than air, and the detectors should maybe be installed in the basements. Comments??

I have installed CO detectors in a couple of homes that had fireplaces. The instructions that came with the ones I installed said to mount no higher than 48 inches above the floor.

Earl, Carbon Monoxide has a vapor density of between 0.97 and 1.0, meaning that it is slighter lighter or perhaps the same as air, which is 1.0. I have seen different references on it, but they all put it in that area.

You can look in the NEC handbook in Article 500 and find this info in the huge table they have, you can also find it in the Crouse-Hinds Digest, or you can look it up on the Internet.

I would personally install the combination CO/Smoke alarm and put it on the ceiling. That is what I see here in Utah, where they have been required for some time now.
Ryan

Thank you Ryan I should have pointed out that the detectors that I installed were retro and not in a new home. These were mounted beside of the beds in the bedroom and were for people that were using oxygen. Two of these detectors activated both audio and a strobe light which came with them.

My brain shorted and the thought of the combo type didn’t enter my mind. The only ones that I though of was those that I had installed last fall.
Trumpy has me holding my horse over in the General Discussion Area and I am wore out from holding on to his tail so I will blame it on him.

CO detectors are not, in my opinion, something that should be mandated.

I dislike combination CO/smoke detectors, as they address different problems. In my opinion, this means they should be used differently.

Smoke detectors have nearly 30 years of employment, and their use is widely understood. There is, in the case of smoke detectors, something to be said for locating them where they are likely to be near a source of fire. (We place them atop staircases because smoke will be "drawn" there.)

CO detectors have a different use all together.
First of all, CO has a cumulative effect. It also, as Ryan pointed out, is essentially the same density as normal air.
Unlike smoke, CO is normally produced, and diluted to safe levels by the room air, or vented.

A major principle in alarm installation is to prevent false alarms. Placing a CO detector in a furnace room might seem like a good idea- but is sure to false alarm every time the main burner ignites (the large flame bloom produces a momentary 'bubble of CO, thet is quickly diluted or vented).

In my home, the smoke detector is just outside the bedroom; the CO detector sits on the night table, next to the bed.
I am primarily worried about CO that I might breath, while I am asleep and unaware. A review of the literature can endorse this location; while such a location would be completely wrong for a smoke detector.

There is also the matter of different alarm life-spans.
A photoelectric smoke alarm can last forever.
An ionisation type smoke detector has lost most of its' sensitivity after ten years.
A CO detector has a definite lifespan, and will not operate after five years.

CO detectors will also alarm if:
-exposed to natural gas; or,
-exposed to freezing temps.


The NFPA has a "standard" for CO detectors, which is essentially useless. The standard says "follow manufacturers' instructions.' Keep your $25.

In MA we are required to install one on any direct vent furnace, boiler, or water heater. It needs to be on the same breaker as well. I do a lot of furnaces for Keyspan and boilers for contractors and it just adds to the bill.

Thats exactly right. Its the NFPA 720, and it doesn't say much. There were proposals made to get tehse into the IRC for 2003, but such were shot sown due to having no good standard to reference (720). I agree with John, these should not be required.

My understanding follows some of the other posts. CO neither rises nor sinks, and is most dangerous while you're sleeping. Therefore, pillow-high near the bed (or other sleeping areas) seems like the best place to me.

Dave

Here in NJ CO detectors are required, and have been for a few years. Policy that I know of is to 'follow mfg instructions'.

We have a two page 'official' paper, but...it's not written well.

Basically, IF there is a fuel burning appliance, a CO detector is required. One on each level (floor) where there are sleeping rooms. Battery and 'plug-in' types are allowed, as are combo units.

I'll get a copy of the official paper Monday, and if I have time, transcribe it here.

John

Thanks guys, you have cleared it up for me. I checked the internet, and found a webpage that suggests the CO detectors be installed outside the sleeping areas, on the ceilings. Right where the CT public act requires it.

If you are in a house that doesn't burn amything (all electric) is a CO detector still worth doing? Where is the CO coming from?

The new code rule has an exception: If your house does not burn any fossil fuels, and does not have an attached garage, and does not have a fireplace, you do not need a CO detector.