Well, the answer to this question is BOTH(Usually NO and sometimes YES!)...Surprised or confused? Trust me, it's based on experience! The answer totally depends on what type of sensor/alarm/detector is being used. NO for Ionization Based Sensors but YES for Optical Based Alarms!
There are basically 2 types of smoke alarms I know of: Optical and Ionization.
A Brief Overview:Optical Based Alarms(photoelectric) - these are usually found in industrial/commercial buildings/establishments.These alarms are what some would describe as those using invisible beams to detect smoke or fire. Though vapor from electronic cigarettes may not be as thick as the ones from fire, it can still trigger it once the smoke vapor hits the sensor. So basically, you do NOT want to blow directly to an optical sensor.
Ion/Ionization Based Alarms - are the typical alarms we use at home. Commonly found in residential houses and some establishments. These alarms analyzes air particles that come through it and triggers when smoke(from fire) particles(e.g. carbon monoxide) pass through the device/alarm.
Here are Some Actual Videos to Prove it
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