A question that all new vapers eventually ask is “will the vapour from my e-cig set off a smoke alarm?” The very simple answer to this is yes, it will- and I speak from experience here. I have fallen foul of smoke detectors many times when vaping in unfamiliar places.
I remember once setting off the smoke alarm while I was staying in a hotel in Riga, Latvia. I had been vaping a high VG e-liquid and I hadn’t noticed that I had been sitting directly underneath a smoke alarm, so as I happily blew out my thick clouds, the sudden high pitched and incessant whining of the smoke alarm was totally unexpected. Like headless chickens, me and my panic-stricken partner frantically tried- and failed- to find a way of stopping it. A few minutes later there was a loud banging on the door by an angry uniformed security guard. Obviously convinced that somebody had been smoking, he demanded to enter the room. Fortunately, all of the vapour fog had dissipated by that time, so there was no obvious evidence that anything untoward had taken place apart from the strong sweet custardy smell (vaping was virtually unknown in Latvia at that time, but I had instinctively hidden my e-cig). I just tried to look as puzzled and confused as him, as he sniffed around the room in a futile attempt to find any evidence of smoking. He eventually gave up his search, shrugged his shoulders and left- phew!
So how can an e-cig set off a smoke alarm when there’s no actual smoke? To answer that question, we need to look at the three different types of smoke alarm.
Ionisation alarms: These types of alarms are sensitive to small particles of smoke. Inside them are two electrically charged radioactive plates and when smoke particles enter the fire alarm, they disrupt the electricity between the plates, setting off the alarm. Electronic cigarettes can definitely set off this type of alarm.
Optical alarms: Optical alarms work by having a beam of infrared light inside them. When smoke particles enter the smoke alarm, the particles cause the infrared light to be scattered onto a light detector which triggers the alarm. Electronic cigarettes can definitely set off this type of alarm, too.
Heat alarms: Used in kitchens, these are unlikely to detect vapour as they are responsive to heat rather than to smoke. You’d probably be safe to vape underneath one of these.
If you are going to vape in your hotel room, it’s a good idea to notice where the alarm is before you start vaping and use your e-cig a safe distance away from it or, if you must blow large clouds, sit by an open window (although you then risk some busybody reporting you to reception). Better still- just use the en-suite bathroom and if you still manage to set off the alarm, you can blame it on the steam from the shower.
According to Boeing’s website, smoke alarms on aircraft are extremely sensitive. In 2014, businessman Rory Sutherland spent a night in jail for using an e-cig on Qatar Airways. This might be seen as an extreme example, but you could easily be given a hefty fine or blacklisted by the airline if you attempt to have a stealth vape in the aircraft toilet and you do set the smoke alarms off. My advice is to avoid all the potential embarrassment and inconvenience of having your e-cig confiscated and just wait until you have landed and are at the luggage carousel before you even think about vaping.