Comment by Reason077
8 years ago
Modern smoke detectors seem to have done away with ionization in favour of optical technology, and so no longer contain radioactive materials.
Bad news for mad scientists!
8 years ago
Modern smoke detectors seem to have done away with ionization in favour of optical technology, and so no longer contain radioactive materials.
Bad news for mad scientists!
You can get both. I recently bought a twin pack containing one of each. The optical one is marketed as "toast proof" so you can put it near the kitchen and the alpha source one is claimed to be more sensitive.
Radioactive ones are usually cheaper but come with plenty of warnings about not disassembling or ingesting the source. Best to have a mix spread around the home. It's also well worth having a CO alarm if you have non-electric heating/cooking.
Are you sure about that, I thought ones with Americium were more sensitive? I'm pretty sure you can still get both.
Edit: Seems I'm not right regarding sensitivity, wiki says:
"Ionization detectors are more sensitive to the flaming stage of fires than optical detectors, while optical detectors are more sensitive to fires in the early smouldering stage"
Wow it also says:
"Where an ionizing smoke detector has been the only detector, fires in the early stages have not always been effectively detected."
That's worrying.
Less sensitivity (or rather, being able to have a higher threshold for sounding the alarm) is actually a good feature for general domestic applications.
You don't really want the thing going off every time someone burns a bit of toast or it just becomes an annoyance, and therefore at risk or being removed or disabled.
Yeah that's true, I guess personally though I'd rather put up with some false positive alarms from toast etc.