Humidity & Smoke Detectors

By William Norman

Smoke detectors perform a crucial role in keeping residents safe, but humidity can create a panic where no emergency exists.

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Humidity from bathrooms can set off a smoke detector.

Smoke Detectors

Smoke detectors employ either photoelectric or ionization sensors to "see" smoke, sounding an alarm to warn occupants, according to the Durham Highway Volunteer Fire Department.

Humidity

Any factor that causes condensation can cause a smoke alarm to go off mistakenly. While cold weather sometimes has this effect, steam or other extreme humidity can also set off the alarm.

Bathrooms

The use of hot, steamy water in bathrooms can cause a nearby smoke alarm to sound, even with the smoke alarm positioned down the hall, because the steam can escape from the bathroom and drift into the hallway.

Preventing False Alarms

Since ionization smoke alarms react more readily to steam than photoelectric alarms, placing photoelectric alarms near bathrooms or kitchens may reduce false alarms.

“Hush” Feature

The Durham Highway Volunteer Fire Department notes that some ionization smoke alarms include a button that silences the alarm for 15 minutes, which may allow enough time for the offending steam to disappear.