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ArcticMyst Security by Avery

Extremely sensitive fire alarm!

Cheech

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Mar 29, 2010
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I'm a fire alarm systems agent and sometimes wonder about the radioactive material in the smoke detectors. I move boxes that have like 60 detectors each, very close to my chest frequently. I've never had a problem with light and optical sensors, they're usually designed in a way that light would light would have a very hard time reflecting into the IR path due to all the plastic barriers (they are also black non-reflective plastic inside). I would actually love to be able to set off a optical sensor with one of my lasers, that would make testing go a lot quicker. We use a magnet on a telescopic pole to activate the detectors that are in high or hard to reach areas. If I could just shoot the vent with a laser that would be tits.

And no I don't use smoke detectors in my house because of cooking. But I do have one above my washer and dryer because they are in a separate room and I think the smoke would take a while to get through the door.
 
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Cheech

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My next build will be a IR laser and ill give it a try. I don't see them that much.
 
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This may be the single most depressing and disturbing thread I've ever read on this forum. At least a couple of people on here agree that smoke alarms are a good thing to have around.

I knew 2 people who died in the same fire in their college frat house. It was actually a pretty small fire at first, it started in a small trashcan. And a WORKING smoke alarm would've warned them with time to spare to get out of the house or put the fire out while it was still small. By the time they woke up, it was too late. One of their friends did manage to survive, but broke multiple bones jumping out the window.

With a WORKING smoke alarm, the fire likely could've been put out by their fire extinguisher before it got any larger than the single, small trashcan that it started in. Or they at least would've had time to get down the stairs and out of the house. Instead, they're both dead, because there wasn't a WORKING smoke alarm on that floor of their house. I wasn't particularly close to either, but some of my best friends still have giant holes in their lives from that accident.
 
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Agreed, if you must disable a smoke detector it is very important to make sure to put it back when you are done. Luckily the radioactive sensor AC + battery powered ones in my house do not pick up the particles from my fog machine (unless you use a ton of fog).

Cheech - I wouldn't worry about moving the boxes of smoke detectors. When they're still in the smoke detector the housing prevents most of the radiation from leaving. All that remains is some mild beta and gamma, at levels that are insignificant.

I have a bowl and cup that have a glaze which contains uranium and they are far more radioactive than the smoke detector source. I have an old civil defense geiger counter to measure stuff with :beer:
 
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I just accidently set off my fire alarm from only using about 10 matches to get a slightly smoky environment for my laser :p Hell, I bet you couldn't do anything with smoke in this room, lighting a sheet of paper on fire would probably set it off....anybody else got sensitive fire alarms too?

Same in my house in Canada.
Tenant downstairs cooks and the fire alarm will sound! This often happens with Ionization alarms due dirty sensors or radon daughters in the chamber. Even dust can set of the chamber if it contains anything remotely conductive.

Here in Korea, nobody has a fire alarm and they are considered decorative items. Our school office downstairs burnt to the ground last year May. Alarm never triggered.

I rather have an over active alarm than none.

For the record the isotope in the Fire alarms is Americium 241, which is strictly used as a Gamma and Alpha source emitter. Beta from Am241 is unusable.
Americium like it's not to distant relative decay product Plutonium 241 is also heavy Alpha producer. It is also highly toxic and can be easily absorbed into the skin.
Alpha is a strong Ionizer and perfect for detectors.
(FYI) or maybe you knew this? Never remove the cover from the ion chamber. Not only will you compromise the detector but you are breaking the law as set out by the NRC. A while ago on Ebay
a fellow sold the ion chamber elements (0.9uCi) as an educational ionization source. He was fined a nearly spent time in prison! This was the era of freedom and prosperity under G.W.Bush, come to think of it.


Orange Fiestaware is REALLY fun stuff to use a Geiger counter on! Some of it will give you a decent radiation dose, still pretty harmless but still toxic. Anyone want nuked Natchos?
 
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