Smoke Alarms

[wabmester]

We lost power the other day, so we lit some candles, fired up the Tulikivi, and all 6 of our smoke alarms went wild.

It wasn't the smoke. I broke one of them while I was changing a battery a while back, couldn't find a compatible replacement, so I replaced it with a battery-powered model. When the power went out, the normally AC-powered smoke detectors started screaming that one of their brethren was no longer in series. Although it sounds just like a regular smoke alarm, and you can't turn them off.

I hate these things. When a back-up battery starts to die, they'll start singing, and it's very hard to locate which one is in pain. And they're all about 20ft off the ground, so I have to pull out my monster folding ladder to replace a battery, and I'm sure I'll kill myself from a ladder fall some day.

Does anybody have a smoke alarm system they recommend? Preferably one with a localized backup battery (on the ground), a false-alarm override, and some reliable indicator of which one is failing?

 

[Nords]

The only house fire I've ever had came from a hard-wired smoke detector. Ironically it didn't detect the smoking insulation, but it sure got our attention. And I'm not sure of the logic behind linking the detectors together-- was the designer worried that houses would be too big to hear one without them all going off?

So we don't wire them into the house's electricity. We buy the cheap battery-powered $10 detectors and replace the batteries every year. The polonium or americium source decays over about a decade so we replace them every 10 years.

You can also mount them on the walls instead of the ceiling. Sounds like the architect was a sadist, too!

 

[IDunno]

And I'm not sure of the logic behind linking the detectors together-- was the designer worried that houses would be too big to hear one without them all going off?

That's exactly why. Imagine being in the living room with the TV blasting, or asleep.

The *MOST* important thing is that you have smoke detectors, and they are in working order (read: the batteries work).

Most people don't realize this, but when you are sleeping, you won't wake up if there is smoke in the room.

We buy the cheap battery-powered $10 detectors and replace the batteries every year.  The polonium or americium source decays over about a decade so we replace them every 10 years.

Replacing them every 10 years is indeed important.

For people with 20' ceilings, a battery-operated smoke detector with a 10-year battery works out very well. When it's time to change the battery, you just replace the whole smoke detector.

You should have at least one on each floor, and at least one in each bedroom.

You can also mount them on the walls instead of the ceiling.

Just be sure to put them at the top of the walls. If it is in the middle, it may not detect the smoke until the room is half full of smoke.

While we're on the subject, many people check their smoke detectors twice a year when the time changes. At the same time, it's a good idea to turn off all your circuit breakers and turn them back on again -- there's apparently a fire hazard there if they never get switched. And, occasional chimney sweeping reduces another fire hazard, even if you don't have a fireplace, but it is especially important if you use those fake logs ("duraflame"?). Chimney sweeping is also a good idea when you buy a new (used) house, as you probably have no idea when it was last cleaned.

FWIW, I spent a lot of time volunteering for the local American Red Cross Disaster Action Team, where I've been to hundreds of house fires, which is where I picked up some of the above tips.
-Scott

 

[wabmester]

Most people don't realize this, but when you are sleeping, you won't wake up if there is smoke in the room.

Not only that, but if you're a deep sleeper (like most kids), even the smoke alarm probably won't wake you. (I saw it on TV, so it must be true )

 

[Nords]

I still think the house-linked smoke detector system was invented by a sadistic submarine engineer who neglected to wear his hearing protection.

A 10-year battery, hmmm? I dunno... I'd love to see Consumer Reports test that one. If they were the size of 9V batteries I'd put one in every VCR in the house.

At the same time, it's a good idea to turn off all your circuit breakers and turn them back on again -- there's apparently a fire hazard there if they never get switched.

I'm calling urban legend on that one. Perhaps that's mixed in with the good idea to test GFCI breaker trips every month or so.

Most of my sea duty circuit-breaker fires were caused by operating them for "maintenance", whether there was a good reason for doing so or not. One of them was caused by a 40-cup coffee pot but that's another story...

All of my shore duty circuit-breaker fires were caused by rodents. So don't store pet food in your circuit-breaker box!

Moisture, heat, corrosion, dust, and general poor design can cause breakers to degrade over years of homeowner neglect. The theory that operating them may prevent any of that from happening hasn't been validated by any research that I'm aware of. (Maybe TH can quote a study by UL or some other electrician's lobbying group.) However operating a breaker suffering from an excess of any of the above is a pretty good way to generate an impressive arc that may reach out to touch you.

Imaging the breaker panel with an IR camera is one of the best ways to find high-resistance hot spots. But I'm still waiting for that good deal to filter down to the consumer-affordable level...

 

[wzd]

You might want to check with a home security company and see if they have anything. It was already installed when we bought our house, but the fire alarms are wired together, and to the home security center. It has a small (well, maybe not so small - 2x3x4"), trickle charged battery in it. When we test the fire alarm, they all sound, and the security center alerts it as well (and if it was monitored, which we have not had done, I guess the monitors would know too).

In this area, it is building code that the alarms must be wired together. Found this out when we refinished the basement....

We have no problem with the alarms sounding when the power is out.

 

[IDunno]

A 10-year battery, hmmm?  I dunno... I'd love to see Consumer Reports test that one.  If they were the size of 9V batteries I'd put one in every VCR in the house.

They *are* 9V batteries. Exact same size. Lithium maybe? Of course, they won't last 10 years in many devices that use 9V batteries, but they are designed to last 10 years in smoke detectors. A Google search for '"10 year" smoke detector' turns up a lot of hits.

I'm calling urban legend on that one.  Perhaps that's mixed in with the good idea to test GFCI breaker trips every month or so.

It could be, but I believe I heard it from a firefighter (it might have been one of the arson investigators). Take a look at http://ottawa.ca/city_services/fire/9_2_8_en.shtml ("Twice a year ... check circuit breakers for free operation"). http://www.tigerhomeinspection.com/docs/electric.pdf says to do it to "maintain good mechanical contact".
http://www.hgtv.com/hgtv/remodeling/article/0,1797,HGTV_3659_2518985,00.html says "Once a year turn all circuit breakers off, then on, to clear the contacts of any corrosion. It's important that breakers are able to move easily, or they won't be doing their jobs."

I'm guessing the issue is that if you leave the circuit breakers alone for years, they could get stuck, and not trip when they are supposed to.

I'd rather be alive and laughed at for spending a couple minutes a year doing something that turns out to be an urban legend, than die because of some advice from someone I don't know. The "experts" at the URLs above certainly could be wrong, but I wouldn't bet my life on it.
-Scott