How ionization smoke alarms work

Specific Inspection Topics Electrical Inspections
1

Wish this guy made more videos. This is a much better explanation of smoke alarms than I ever got.

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But, do you now understand better how they work???

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3

yea absolutely.

specifically, it makes it clear why the test button only tests the device’s ability to sound the alarm, not its ability to detect smoke.

I’m a little cloudy still on the interaction between the radioactive element & the battery. chemistry has never been a strong suit. but yes, definitely understand it better.

4

Very interesting. Good explanation.

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Nice video and I learned something, but not the big question…why do they last only 10 years? The usual answer is vague about an accumulation of dust/smoke particles over time that interferes with the responsiveness. If that is the only reason, then couldn’t we take a can of compressed air and blow them clean? Maybe the radioactive material degrades (if ionizing as shown in the video)? Ok, then just say that, but they don’t.
I’ve smoke tested 40 year-old detectors that reacted pretty darn fast. BTW, I no longer do smoke testing. If it’s old, I follow the guidelines and recommend replacement.
Of course, now we have contained units with 10-year-life lithium batteries that cannot be changed. That cynical side of me suspects that a marketing plan involving designed obsolescence might be the hidden real reason for the replacement recommendations.

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The same here, Lon… :heavy_dollar_sign:

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I knew it! the radioactive material decays. unless someone wants to prove our AI masters wrong.

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Some of the old photoelectric detectors, the test button is actually a stick that drops into the smoke chamber, setting off the alarm…

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Where did you find that? Interesting comment about regularly cleaning or maintaining detectors. I have not seen that before.

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LOL, I didn’t read that part. that was generated by Chat GPT. The technology still requires some careful review… although maybe it is technically true, albiet impractical

11

The reliability drops off as the alarm ages, hence the 10 year lifespan.

The 10 year nonremovable battery is to prevent people from forgetting to change or remove the battery and leaving themselves no protection. Also a convenience not having to access the alarm on a regular basis.

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