Where does this come from, and can I check it?

Radioactive americium ionises air inside sensing chambers to detect smoke particles. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a everyday life fact?

Yes. It sits on the Everyday Life shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Ionisation smoke detectors contain a microscopic trace of americium

Radioactive americium ionises air inside sensing chambers to detect smoke particles

Ionisation smoke alarms utilise a tiny, harmless sample of americium-241 to ionise air particles inside a sensing chamber. The ionised air allows a small electrical current to flow continuously between two electrodes. When microscopic smoke particles enter the chamber, they disrupt the current flow and sound the alarm.

Where this comes from

NIST

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Tags: safety, sensors, radiation

Ionisation smoke detectors contain a microscopic trace of americium: the short answers

Where does this come from, and can I check it?: Radioactive americium ionises air inside sensing chambers to detect smoke particles. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a everyday life fact?: Yes. It sits on the Everyday Life shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.