Well there seem to be two kinds, ones with radiation hazard stickers and
ones without,both seem to give false alarms at times. I think the former can
decay so they just don't work at all once the radiation reduces to the point
where nothing gets ionised.

Brian

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"NT" wrote in message
...
On Nov 11, 3:36 pm, "john east" wrote:
Have an ordinary house smoke alarm. It's about twenty years old and it has
recently gone off in the middle of the night for two days running and for
no
apparent reason.

I've heard that it might need a vacuum cleaner applied to it. Is there
likely any truth in that, or is there anything else i might usefully do?

Or does it probably mean that I have to replace it?

clean it out, fit new battery, see if it behaves. I dont think theres
much else one can do with them. Except build a nuclear power plant...
google radioactive boy scout.


NT