According to Best Practices for DOT Random Drug and Alcohol Testing:
What’s the best tool employers have for deterring drug and alcohol use in the workplace?
Random Testing. And, here are just a few of the reasons why:
· Saves lives and prevents injuries.
· Helps employers identify workers with substance abuse issues and facilitate their treatment.
· Allows employees to easily say no to illegal drug use. "No, thanks. They drug test at work.”
· Reduces employer liability.
· It is a fair way of testing.

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Random testing is required for safety-sensitive employees

Each DOT Agency and the USCG has regulations that require certain employers to
implement a random testing program.
Industry
Regulation
FAA - Aviation
14 CFR Part 121, Appendix I, V, .iVB and
14 CFR Part 121, Appendix J, III, C

FMCSA – Motor Carrier
49 CFR Part 382.305

FRA - Railroad
49 CFR Part 219.601 and 219.607

FTA - Transit
49 CFR Part 655.45

PHMSA - Pipelines
49 CFR Part 199.105

USCG - Maritime
49 CFR Title 46 Part 16.230

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Who gets tested?
Regardless of job titles like supervisor, volunteer, contractor, owner operators, etc., people are chosen for testing based on their job function (known as a safety-sensitive function) not their occupational title.


You say Legistors - I say toe-may-toe
You say Executive Branch - I say two-maw-toe
You say SCOTUS - I say all three branches of the government have safety-sensitive functions. You may have heard that politicians in an Australian state could be breathalysed before voting. Timid little half-hearted steps like this may be OK for our beer-swilling friends down under, but we can do better than that. I say we test our Senators and Representatives, not just before every vote, but also as they go about their daily business of being massaged by lobbyists and raking in campaign contributions. The people we elect need to be thinking clearly as they compromise themselves, so they can get the best deal possible. The President should always give a UA before giving the State of the Nation. I say that if people can't be trusted to steer a train without drug and alcohol testing, it is even more important to have drug and alcohol screening for those steering the country. Otherwise the whole country could end up in a train wreck!