Bugs is the most likely cause, not humidity.



On Tue, 12 Jun 2007 11:40:27 -0700, terry
wrote:

Within the last year or so there were postings here about smoke alarms
that had sounded for apparently no reason. Batteries were good etc.
Somebody mentioned a smoke alarm in close proximity to a shower that
had triggered and we mentioned our own experience a few years ago
where a smoke alarm in the passageway outside bedrooms in my daughters
house had sounded, for no apparent reason, on a warm/humid day.

Recently we finally had what are, for here (North Eastern tip of North
America), a couple of much warmer and humid days. I mean around 78-80
F and sorta sticky! Now I know that's nothing to even mention, having
just come back from the Middle East where it hit +43 Celsius or
approximately 118 Fahrenheit! But around 80 is,-for here, warm;
phew!!!!

I had front door screen open and other windows open letting the
breeze blow through. Suddenly the smoke alarm mounted at the bottom of
our basement stairs started sounding on a regular 30 second to one
minute basis. But this was not how these smoke alarms normally sound
if triggered by smoke. Two other both very ordinary battery models, on
the main floor did not sound.

After a quick check to make sure a pan or kettle had not been left on
and/or overheated on the stove etc. removed the smoke alarm from
above the workshop door way in the basement and brought it up to main
floor. Its been on the kitchen counter for week or so and has been
quiet since! Battery tests good, as it should; only replaced a few
months ago.

Supposition: Some of the seasonally warmer humid air coming in through
front door had drifted down the stairwell, had cooled to the basement
temperature probably around 60 degrees F and thereby acquired an
apparently higher percentage of humidity.

This seems to confirm that some smoke alarms can be triggered by
higher than normal humidity?

Thought I'd post this for information and/or possible discussion.
Terry.