Quick answer
Government and municipal employers usually screen at hire, and public-safety roles such as police, fire and corrections carry ongoing random and post-incident testing.
How testing typically works
Pre-employment screens are most common, followed by post-accident and reasonable-suspicion testing in safety-sensitive roles. Federally regulated positions (for example commercial drivers) follow DOT rules with random testing at federal cutoffs. See panel breakdowns and the detection chart.
Frequently asked questions
Do government employers drug test?
Government and municipal employers usually screen at hire, and public-safety roles such as police, fire and corrections carry ongoing random and post-incident testing.
What panel is used?
Most screens are urine panels or mouth swabs run through a certified lab network. Any non-negative screen is confirmed by GC-MS or LC-MS/MS and reviewed by a Medical Review Officer before it is reported.
How long do drugs stay detectable?
It depends on the substance and specimen — see the detection chart. Hair covers up to 90 days, urine days to weeks, and saliva and blood much shorter windows.