Are Weed Vape Pens Safe? Do Dabs Smell? A Guide to Discreet Cannabis Consumption Puffco If someone smokes outside, do they bring thirdhand smoke indoors with them? Thirdhand Smoke Resource Center Is Vaping Marijuana Safer Than Smoking? How Long Does the Smell of Cannabis Last? CB1 Medical Do you know the signs your teen may be vaping cannabis? Cannabis vape pens are small, discreet, and easy to hide and many parents don't even know what to look for.