I'd start laughing if the cops starting search bags and then pulled that thing out! Just crop dust them while they're using that thing, they'd love it!
Smoked a cigar once, the next day mom asks why I smell like cigarettes and lectures me on how horrible smoking is..Smoke an eighth of some OG Kush, the next day she doesn't even question me..So tell me more about this pungent scent
They cant measure the PPM because it would be breaking laws requiring a court order or warrant, the nose allows them to just say probable cause "It smells like weed" and fuck you.
aka now they can bullshit probable cause more then ever before.
I don't think it even picks up smells. They just wait to see what group of people are laughing uncontrollably at them using this thing then arrest them for cannabis consumption.