# Why aren't smoke alarms fire proof? **URL:** \ **Category:** Factual Questions\ **Created:** [May 2, 2001, 5:19pm UTC](https://boards.straightdope.com/t/why-arent-smoke-alarms-fire-proof/64109 "2001-05-02T17:19:51Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![handy](https://avatars.discourse-cdn.com/v4/letter/h/b5a626/32.png) [@handy](https://boards.straightdope.com/u/handy)\ **Post date:** [May 2, 2001, 5:19pm UTC](https://boards.straightdope.com/t/why-arent-smoke-alarms-fire-proof/64109/1 "2001-05-02T17:19:51Z")
They all seem to be encased in cheap white flammable plastic. So, why not put them in a metal fire proof case? ---
**Author:** ![dolphinboy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dolphinboy/32/330_2.png) [@dolphinboy](https://boards.straightdope.com/u/dolphinboy)\ **Post date:** [May 2, 2001, 5:50pm UTC](https://boards.straightdope.com/t/why-arent-smoke-alarms-fire-proof/64109/2 "2001-05-02T17:50:49Z")
That’s easy… because the smoke alarm is suppose to warn you of a fire… not survive one. Spending a lot of extra cost to make your smoke alarm surive a fire may sound like a good idea but they are designed to detect smoke and heat and by the time they are engulfed in flame your probably don’t care anyway… They are made of cheap plastic so that everyone can afford to buy a few… would you want a smoke detector that costs $150? ---
**Author:** ![Guy\_Propski](https://avatars.discourse-cdn.com/v4/letter/g/5e9695/32.png) [@Guy\_Propski](https://boards.straightdope.com/u/Guy_Propski)\ **Post date:** [May 2, 2001, 8:27pm UTC](https://boards.straightdope.com/t/why-arent-smoke-alarms-fire-proof/64109/3 "2001-05-02T20:27:47Z")
If your house is hot enough to melt the plastic of a smoke detector, then it was probably sounding for some time already. Also, making them out of metal would make them more expensive. You want to encourage people to use them, so make them cheap and easy to install (two screws, no lag bolts needed). ---
**Author:** ![handy](https://avatars.discourse-cdn.com/v4/letter/h/b5a626/32.png) [@handy](https://boards.straightdope.com/u/handy)\ **Post date:** [May 3, 2001, 2:16am UTC](https://boards.straightdope.com/t/why-arent-smoke-alarms-fire-proof/64109/4 "2001-05-03T02:16:20Z")
“would you want a smoke detector that costs $150?” Thats about how much the one I should buy costs. Its the only special one they make for the Deaf. sigh ---
**Author:** ![Rosebud](https://avatars.discourse-cdn.com/v4/letter/r/ea666f/32.png) [@Rosebud](https://boards.straightdope.com/u/Rosebud)\ **Post date:** [May 3, 2001, 4:01am UTC](https://boards.straightdope.com/t/why-arent-smoke-alarms-fire-proof/64109/5 "2001-05-03T04:01:54Z")
**handy** , how does the alarm work? I’m guessing with lights? My office is equipped with alarms featuring both a piercing siren noise and a really intense white strobe. I’m a hearing person, yet frequently when we’re about to have a fire drill it’s the lights that give it away to me first-- they seem to kick in just before the noise starts, and it’s hard to miss the flashing. ---
**Author:** ![handy](https://avatars.discourse-cdn.com/v4/letter/h/b5a626/32.png) [@handy](https://boards.straightdope.com/u/handy)\ **Post date:** [May 3, 2001, 3:09pm UTC](https://boards.straightdope.com/t/why-arent-smoke-alarms-fire-proof/64109/6 "2001-05-03T15:09:08Z")
It has to be connected to the main wiring. You get I think at least 90db alarm & a light powerful enough so that the neighborhood is illuminated. Most deaf people can hear something that loud. ---
**Author:** ![Montfort](https://avatars.discourse-cdn.com/v4/letter/m/d6d6ee/32.png) [@Montfort](https://boards.straightdope.com/u/Montfort)\ **Post date:** [May 3, 2001, 3:30pm UTC](https://boards.straightdope.com/t/why-arent-smoke-alarms-fire-proof/64109/7 "2001-05-03T15:30:40Z")
> [@](#): > > \*Originally posted by handy \* > \*\*Most deaf people can hear something that loud. \*\* _Hear_ or _feel_ something that loud?