I manage an oilfield service company and my guys need to take a piss test every three months to be on the majority of our customers work sites. Piss tests are a joke and only "weed" out pot smokers. The hard drugs are out of your system in a day or two. But if my guys want to make $30/hr then they need to piss clean, that's the way it works. Some of them don't do drugs, some of them do and have their ways to pass... It all boils down to liabilities, if something happens companies always want to be able to pass the blame down until it can't go any further. If one of my guys has an incident and pisses dirty during an investigation then my company can be held liable for damages. It is a dirty part of business but one that isn't going to get ay better before it gets worse I think.