on all orders over $75.
100% money back guarantee.
Support 24/7

Can You Fail a Hair Drug Test from Second Hand Smoke?

Can You Fail a Hair Drug Test from Second Hand Smoke?


If you’ve ever been in a room where someone else smoked marijuana, you know just how easy it is to inhale the smoke yourself. You’ll likely leave with your clothes smelling like pot as well.

For those that have work or educational commitments that require staying free of drugs, this may cause concern. Many people believe that even if you didn’t smoke yourself, merely being exposed to the fumes could cause a positive test reaction.

Let’s clear up these questions once and for all below.

Can You Fail a Hair Test from Second Hand Smoke?

For many people, the idea of failing a drug test simply because you were sitting in the same room as people smoking weed can be worrying.

But, if someone smokes weed around you, will it get in your system just like that?

Well, there actually were studies done in the 80s that did indeed find a correlation between second-hand marijuana smoke and failed drug tests.

However, it must be noted that the tests were quite flawed. The chances of you testing positive from second-hand smoke are quite slim. Second-hand smoke simply does not get a person high enough for the marijuana to show up on most tests. 

Nonetheless, it is technically possible. And if there was a type of test that would be able to pick up second hand marijuana smoke, it would be a hair drug test. This is because these types of tests are highly sensitive. 

Why It’s Not Enough

The reason why you usually won’t fail a marijuana test because of second-hand smoke is relatively simple. It boils down to the fact that the substance levels the tests look for cannot be present in your body if you haven’t smoked yourself.

For instance, a marijuana urine test is designed to look for byproducts of THC. These won’t show up in your urine in significant amounts if you haven’t smoked marijuana yourself, and have been inhaling second-hand smoke only.

With passive exposure, you are not actually inhaling the THC directly from marijuana and are only inhaling secondary smoke, which contains far less THC than the active smoke that comes directly from the substance.

According to some studies, the levels of THC in second-hand smoke are as much as 100 times lower than in active smoke. These levels are simply not enough to create enough of a high to show up on most tests. There are times when a hair test might still be able to pick up the drug, but the exposure would need to be in an extreme environment with little to no ventilation over an extended period of time. 

It’s safe to say that in 99% of situations failing a drug test from second-hand smoke is not possible. And to improve that number to 100%, the key, as always, is to not participate in activities where smoking will be present.

How Fair Follicle Testing Works

Hair follicle tests are solution often used by parents or employers that have questions regarding the drug use of a child or employee. They can also be used individuals who want to test themselves to find out if a drug is still present in their system. The hair testing provided by Countrywide allows for a full 90-day drug history report based on a sample of 90-120 strands of hair cut from the scalp. These strands should be at least 1.5 inches long. Results of this type of test are usually available in 3-7 business days from the receipt of the sample.

This test is incredibly effective at detecting even minor traces of drugs. They are likely the only test that has the potential to report second hand marijuana use. Hair follicle tests are so effective at picking up second hand smoke inhalation that they have actually come under some scrutiny regarding their reliability in determining whether a person has truly smoked marijuana.

Because of this, when it comes to marijuana, hair tests are considered to not be the most reliable option, at least in situations such as post-accident testing or reasonable suspicion testing. It’s best to use hair follicle tests when there is a reason to believe the marijuana use has been long-term.

Ideally, in situations when second-hand smoke is a potential issue, it is recommended to also use blood tests, which can provide more reliable results. 

Countrywide Testing

The best way to find out whether or not marijuana is in your system or the system of someone you know is always to utilize professional marijuana drug tests. Countrywide carries a wide selection including urine, mouth swab, and hair tests.

If you have any questions regarding the testing process, how it works, or whether or not a certain product is right for your situation, we are here to help. Our support phone number is (469) 389-2120 and you can also utilize our online contact form.