Do Ecigarettes set off smoke alarms?

This is a question getting asked more and more.

I guess the main worry is smoke alarms/detectors in aircraft and restaurant and generally in public places. I would like to answer definitively, however it isn’t quite that simple and the answer is actually yes and no. Not to useful I agree. It may help if I explain exactly why the answer is yes and no.

Basically there are two types of smoke alarm in current use both domestically and commercially.

One is the Photo cell type. These work by a light source shining onto a light sensitive cell In order for the alarm to remain silent, the cell needs light to fall on it. If the cell is obscured by smoke then it will receive insufficient light and the pre-set circuitry will sound the alarm. In the case of this type of smoke alarm it is indeed possible that if enough vapor from an Ecigarette enters between the light source and photo cell, it would obscure the cell sufficiently for the alarm to be triggered. However it must be said that vapor disperses much more easily and quickly than smoke and though perfectly possible it isn’t very likely, unless one is using an Ecigarette very close to a smoke alarm, for example in the toilet of an airplane!

The second type is an ionisation detector inside the ionisation alarms there’s an ionisation chamber with two plates and a source of ionising radiation. The battery sends a voltage to the plates, charging one positive and the other negative. The radiation source, a small amount of an isotope called Americium-241, decays and emits alpha particles (subatomic particles made of two protons and two neutrons) at a constant rate. As the particles travel through the chamber, they ionise, or remove an electron from the oxygen and nitrogen atoms in the air that passes through the chamber. The free electrons, which have a negative charge, are attracted to the positively charged plate, and the positively charged atoms are attracted to the negative plate. This maintains a small but constant current between the two plates. When smoke enters the chamber, it disrupts ionization and lowers or cuts the current between the plates, triggering the alarm. An Ecigarette will have no effect on this type of smoke alarm.

So there you have it. It is unfortunately not possible to tell at sight which is which. So take care if you are close to a smoke alarm as if it is the photocell type, it is just possible to set it off.


    0800 0196445









Please verify that you are 18 years of age or older to enter this site