Been doing research on this one ... and there are the two options others listed above. However, one has to really dig into this to determine if spending $1000+ per sensor (that covers a 12x12 area) and picking out which bathrooms get such a device is going to really solve the vaping problem, or are the students going to learn to start exhaling into their clothing or otherwise picking new places to vape/
E-cigarette liquid is primarily composed of propylene glycol and water or glycerine, along with the nicotene and flavor elements. Wow .. propylene glycol and glycerice are organic compounds, so this outta be easy, right? A good VOC gas sensor should do the trick?!?! No, not so fast. That's not really what's coming out of people's mouth/lungs after they take a drag.
The heating coil that heats the e-liquid to create the aerosol (it's not smoke) that is inhaled contains a myriad of compounds and substances that were't there before the liquid was kinda boiled. What comes out are a cloud of particles in the nano and micro sized range as well as things like toluene, benzene, and even formaldehyde. So, are we sensing VOC's,? There is public research available that shows that there are not measurable amounts of VOCs in the exhaled gas. So, are we sensing, specific post-puff chemicals (are they even in large enough concentrations to pick up?) Are we sensing/counting particles in the measurable range with a sensor not in a lab-type environment?
If we are sensing and counting particles of some specific range, what is to keep other aerosols like perfume sprayers, Axe deodorant, and pressurized cleaning products like Lysol spray from triggering the sensors? This question is not based upon conjecture, as there are end user reports of higher than expected false alarms created by these other sources that have made further deployment of Vape sensors not a done deal. Along with this is the drain on manpower and resources every time someone who is the designated "catcher" has to run to the second floor bathroom to check out who smells like pineapple or search through the VMS to see who was in front of the bathroom door just before the sensor reported an alarm.
The vaping has to stop, period .. people are dying. So investing in ways to stop or curtail the vaping in schools is critically important and has to be on the forefront of every schools' safety and security agenda. I'm trying to understand more about how a vape sensor would really solve the problem, since it is a post-puff measure and one that users are already finding ways to circumvent (by exhaling into their shirts/coats/clothing). You can't have cameras in bathrooms, so a sensor integrated to the VMS could make sense if it works all of the time and is more cost effective. I know strong efforts are being made on the awareness/informing front, on the social media sites, at the peer level, and at the legal level to try and make it harder for minors to get and possess e-cigs, that are probably making as much if not more of a difference, but I suppose at this point, multiple deterrents have to be tried and more resources devoted to those that are showing signs of working.