[spokeshave]

Not wanting to argue with the safety premise, but the usual “pee” test gives results for past 30 days use. Other than being an indicator of past usage, specific to recreational drugs like pot, 30 days prior use does not affect performance and safety. This point is not about harder, more dibilitating and longer effecting drugs.

I think that the "Hair Test" goes back 6 months, and is comprehensive in terms of looking for various drugs.

[spokeshave]

What time period does a standard hair follicle test cover?

A standard hair follicle screen covers a period of approximately 90 days, but is susceptible to time variation depending on the growth rate of your hair. The hair sample is cut as close to the scalp as possible and the most recent 3.9cm (or 1.5 inches) are tested. It is possible to go back even further than 90 days since the time period is limited only by the length of the hair sample, but is standardized to a 90 day history.

What type of drugs can be detected in a standard hair test?

Cocaine (Cocaine & Benzoylecgonine), Marijuana, Opiates (Codeine, Morphine & 6-Monacteyl Morphine), Methamphetamine (Methamphetamine/Amphetamine & Ecstasy), and Phencyclidine (PCP).

These five drug classes are mandated for testing by the Federal Government.