This is an interesting development around the OSHA ruling, which severely restricted workplace drug and alcohol testing if an accident/incident occurs resulting in which the employee seeks medical attention. The logic was that more employees would report incidents, if there were no repercussions of testing.
The ruling scared off many employers from testing, but there was a provision to allow for it, if the employee was in a safety sensitive job category. Most employers did not realize this and we have had to clarify this with many of our clients. But now, legal challenges are forcing OSHA to reexamine the policy. See the link below for a more detailed explanation.
http://www.jdsupra.com/legalnews/lawsuits-challenging-osha-rule-halted-33720/