Smoke/CO Detectors Needed: Your advice please

[Dr. Zuki 1]

My home smoke detectors have reached their expiration dates and I want to buy new ones which are combo units with carbon monixide detection included.

So what do you recommend? I once heard that you should get those which are both photoelectric with ionization.

Your valued advice please !!!!

Thanks Much.

Dr. Zuki

Lawrence Hospital

[firemoose827 324]

"First Alert" and "Safety First" are good units. The thing you need to make sure of is that they are hardwired to your electric with battery back-up. A lot of people just change the batteries annually, but you should also vacuum out the unit and make sure its free of dust.

Check with your local regs on the amount and location of the units, and always feel free to check with your local fire dept and ask questions too.

Hope this helps some. PM Me if you have more questions, Im working on my Codes Officer Cert and will be the Fire Inspector for my village, so Im glad to help any way I can.

Moose

[Guest FFNick]

There are also many units/manufacturers out there now that have a 10 year lithium battery. If it is not feasible to have your smoke detectors hardwired, then this would be the next best alternative.

[antiquefirelt 994]

There has a been quite a bit of controversy over smoke detectors and how well the ionization types work. In MA they have a law banning the use of "ionization only" smokes. This is due in large part to D/C Fleming of Boston Fire who has been studying fire death and injuries where smoke detectors were present, as well as other sources who have been crying foul on them. There seems to be no issue with photo-electric smoke detectors. They also make combination units that use both types. From the last fire/smoke detection NFPA 72 seminar I attended it seems that a new gas sensing technology is going to be the best, but most likely cost prohibitive for anything but museums or other places looking to protect highly valuable property.

Here are a few links about he detector type controversy:

From D/C Flemming

News Release possibly some bias or monetary connection has been question in regard to this.

[jack10562 414]

Doc, you didn't indicate if you had line-voltage interconnected hard wired or stand-alone single station detectors.

There are battery and line-voltage combination ionization smoke / CO detectors, or dual-chamber smoke-only units. I have never seen a "tri-detector" with photo electric/ionization smoke and CO detection, but they may exist.

If you currently have battery-operated single station units, you can get CO/Smoke detectors that create a wireless interconnected system: when one detector activates, they all sound.

Hard-wired line-voltage units may require the services of an electrician, especially if the quick-connect plugs are a different style on the new detectors, and need to be changed.

[SteveOFD 176]

The installation instructions for the brand of Carbon Monoxide Detectors that I install for Security Systems, recommend mounting the Detector at the approximate height of breathing level. This would typically be about five to six feet above floor level.

Carbon Monoxide has a specific gravity of 0.9657 (air being a s.g. of 1). What this means is that when CO is warmed it will rise, while when it is cooled, as it travels further from its source, it will sink. With the Carbon Monoxide Detector mounted at breathing level it would provide a better sampling of the air that a person would be breathing.

As for Smoke Detectors, Photoelectrics are the only type I install (except for Beam Photoelectrics for long range detection in warehouses, etc.). As to what antiquefirelt stated there is mounting evidence as to the effectiveness of ionization type Smoke Detectors. I read about this about two to three months ago. This just happened to one of my customers two weeks ago. The Son burned something on the stove and filled the house with smoke. There is an ionization type Smoke Detector about four feet outside of the Kitchen (approximately ten feet from the stove). The ionization detectors were hardwired by an Electrician during construction and they are all tied together, so they all sound when any one activates. The closest System (photoelectric) Detector that I installed for the Security System is on the second floor. When I tested the ionization detector by the Kitchen, it activated with the test button on the unit and with the canned smoke I use for testing purposes, so the detector is operational. It just did not activate during this incident. The System Smoke Detector on the second floor also tested good. So I do not recommend the use of ionization detectors.