Originally Posted by Stryker

I would be willing to bet your friend was joking with you. Drug tests that involve hair use whats called gas chromatography, which is VERY expensive and cost prohibitive for a business with so many people interviewing. Not to mention there arent very many labs around the country that have the equipment to do it. The military doesnt even use it, and they have some of the strictest standards in the US.

Another thing is that they are more interested in your CURRENT drug status. While urine tests have their flaws (individual's metabolism, duration drugs stay in the blood), it does show repeated use. THC can show up as much as a month to a month and a half after a person quits if they are a regular user. But on the other hand, amphetamines can leave your system in as little as 72 hours.

Lastly, the hair test does not test for drugs you did 10 years ago (unless you are a female who hasnt cut her hair much in that time).... The hair only reflects drugs that were done while the hair was growing. So if you shave your head, its like you are wiping the slate clean. But they can test from body hair, but it typically only allows them to see back up to 1 year. Its just a myth that they can test as far back as they want.