High Times recently got its hands on the infamous Nasal Ranger, the device that can tell you how strong a smell is. Check out what it does, how it works, how it affects the cannabis community, and take a look at our own experiment.
In order to regulate the odor complaints that started coming in strong after recreational cannabis was legalized, Denver’s Department of Environmental Health (DEH) has invested in a few Nasal Rangers. This device can measure how strong any smell is, and people trained in the practice of olfactometry (measuring smell) are being sent out to smell weed whenever they are called.
Complaints about the smell of pot don’t technically concern the police anymore in Colorado, so DEH olfactometers determine whether the smell is strong enough to incur a fine. Even as ridiculous as it looks, the Nasal Ranger could get you in trouble if you’re not careful with the smells you make, but how much does the cannabis community need to worry about the Nasal Ranger?
Designed for the need to assess odor complaints coming from pig farms, sewage processing plants and other smelly, industrial factories, the Nasal Ranger, or field olfactometer, has proven itself when put to the test, even when compared to electronic instruments that measure the air’s exact composition, or E-noses.
Now many local authorities across the nation use the Nasal Ranger successfully to uphold odor regulations.
When it comes to the smell of marijuana, the device acts a little differently. Authorities wielding Nasal Rangers dispatched to the scene of a smelly crime haven’t been issuing violations as much as people thought they would.
The issue with pot boils down to how the Nasal Ranger works. Beautifully simple, the device works by dilution. By comparing the amount of filtered air relative to ambient air, the user smells the odor in question and the device gives you a reading on how powerful any given scent is.
A dial controls the ratio of either ambient air (unadulterated, smelly air) or filtered air that the user breathes in. A carbon filter at the end of the device filters the air. At first, the smeller needs to breathe in carbon-filtered air for about a minute in order to clean their palette, so to speak. Then, the user turns the dial to the second spot, which lets in a little bit of ambient air, but mostly filtered air. The user inhales twice, then switches to the next spot on the dial, which is another blank (all filtered air) so the smeller can clean their palette again. The smeller goes around the dial alternating between blanks, and successively larger amounts of ambient air relative to filtered air.
The spot on the dial that the user first detects a smell tells you the dilution to threshold ratio, or D/T. Strong smells have a very large DT (the largest being 60/1), because the smell is so potent it only takes a little bit of ambient air diluted into the filtered air to detect it. By the same token, a small D/T (1/1) means the smell is relatively weak.
Regulations in Denver state that any odor that reaches the 7/1, or about halfway around the dial from the beginning, constitutes a violation, whether the smell comes from a marijuana farm or a lake of pig feces. The smell of flowering cannabis is strong, but it doesn’t have anything on animal feeding operations and sewage filtration plants. The level set for the Nasal Ranger, designed for factories and farms, is too hardened to be offended by the delicate aroma of flowering, dried or smoked cannabis. People call and complain because of what the odor is, not necessarily because it’s strong.
While this is good news for the cannabis community, it doesn’t give anyone impunity. People still should be be wary of their neighbors; even if the smell isn’t strong enough for the Nasal Ranger, if you receive “five or more complaints from individual residents representing separate households within a 12-hour period and the complaints are related to a single odor source” you could still get fined anywhere from $150 to $2000. To make that kind of stink you’d have to smoke an entire crop’s worth of ganja, so make sure to go to an open space where it’s allowed, like the Cannabis Cup.
High Times also did a relatively controlled experiment with the Nasal Ranger to see how it works for a pot-like aroma. It definitely puts your poker face to the test; it’s hard to avoid laughing while holding the device to your face, which messes up your breathing and lets air in the sides, messing up your measurement.
We measured the smell of myrcene, an important terpene present in most strains, with especially high levels in sativas. By saturating the air in a small office with the pungent and floral myrcene, we recreated the same potency of smell that an ounce of stinky bud sitting open on the table would make, or even smoking a bowl.
Next, we broke out our Nasal Rangers and got to smelling. It took a few tries to get the method down, but we were able to get consistent results from a room saturated with the smell of myrcene. Would the smell have been a violation according to Denver DEH authorities? Just barely; the smell averaged at a 7/1 D/T.
Our conclusion is that the smell of cannabis just isn’t a strong smell on its own when you compare to actual offensive odors like those coming from pig farms and chemical factories. It seems like the reason Denver citizens file odor complaints about marijuana isn’t because the smell is strong, but because they just don’t like the smell at all. The Nasal Ranger weeds out these complaints biased against pot, making it a great tool for objectively upholding an odor regulation.