Drug Testing for Employers: Rules and Options

Four federal rules, four different questions

No federal law requires every private employer to drug test. One federal program requires testing for certain jobs (the Department of Transportation's, for drivers and other safety-sensitive transportation work). One requires a drug-free workplace policy from federal contractors and grantees but says nothing about testing. One, the ADA, decides how a test fits around disability law. And the FCRA steps in when a screening firm, rather than the lab, hands you the result. Everything else (whether you may test at all, when, for what, and what you may do with a positive cannabis result) is mostly state law.

So the first question for a small employer is which of your jobs, if any, fall under DOT. Those run on a fixed federal program you cannot vary. Every other job runs on your own written policy, shaped by your state's testing statute. Keep the two programs apart: DOT says its tests “must be completely separate from non-DOT tests in all respects”. If you also check driving records, the MVR guide covers the DOT driver file that sits beside the testing program.

DOT testing: when federal rules require it

The Department of Transportation's testing rules reach safety-sensitive transportation jobs, each through its own agency rule, and every test runs by the same procedures in 49 CFR Part 40. For most small employers the one that matters is the trucking rule: Part 382 applies to every employer of a person who drives a commercial motor vehicle and needs a commercial driver's license. An owner-operator who employs only themselves still has to sit in a random pool of two or more drivers.

A DOT drug test checks five drug classes: marijuana, cocaine, amphetamines, opioids and PCP. The lab may not test a DOT specimen for anything else. Part 40 now provides for urine and oral fluid specimens, an initial screen and a confirmation test at the lab, and review by a medical review officer (MRO), a physician who checks for a legitimate medical explanation before the employer is told the result.

Two more pieces come with the program. Before a driver's first safety-sensitive shift you run a full query of FMCSA's Drug and Alcohol Clearinghouse with the driver's consent, then query every driver at least once a year. And each driver gets your written materials on the rules before testing starts, including who answers their questions, what counts as a refusal and what happens after a violation. Supervisors who make reasonable-suspicion calls need at least 60 minutes of training on alcohol and another 60 on drugs.

Federal contractors and grantees: the Drug-Free Workplace Act

If you hold a federal grant, or a federal contract above the simplified acquisition threshold (contracts for commercial products and services are carved out), the Drug-Free Workplace Act sets seven conditions. Read them closely and notice what is missing: none of them is a drug test.

A contractor may still choose to test under its own policy. That is a company program like any other, and your state's testing law governs it; the Act gives it no cover. New York's labor department, citing a U.S. Department of Labor notice, puts it plainly: neither the Act nor the rules under it authorize drug testing of employees.

The ADA: a drug test is not a medical exam

That one sentence is why employers covered by the ADA (15 or more employees) may test applicants for illegal drugs before an offer, where state law allows it, while the ADA bars medical exams until after a conditional offer. The next sentence keeps the ADA neutral: it does not “encourage, prohibit, or authorize” drug testing. And an employee or applicant “currently engaging in the illegal use of drugs” is not protected when you act on that use.

The protection runs the other way for people in or through recovery. Someone who has completed or is in a supervised rehabilitation program and no longer uses, or who is wrongly regarded as using, keeps the ADA's protection; you may still test them to make sure they have stopped.

When a drug test result is a consumer report

Whether the FCRA applies to a drug test depends on the route the result takes to your desk. FTC staff answered the question in a 1998 opinion letter, and their 2011 staff report repeats the core of it.

If you order the drug screen through the same screening firm that runs your background checks, the result arrives as a consumer report, and the FCRA steps apply to it exactly as they do to a criminal search: the stand-alone disclosure and written permission before the test is ordered, then the pre-adverse notice with a copy of the report and the Summary of Rights before you withdraw an offer over the result, then the final notice. Our guide to what a consumer reporting agency is explains why the route matters.

State cannabis rules: seven states, read one at a time

Cannabis is where state law and drug testing collide most often. Federal DOT rules still test for marijuana metabolites, and state protections give way to them. For every other job, several states, including the seven below, limit what you may do with off-duty use or a positive cannabis result, and some limit the test itself. The seven below were read from each state's own statute, labor agency or cannabis regulator on October 23, 2026.

Test types and panels: a DOT program next to your own

Outside DOT, you design the test. Inside DOT, the design is fixed. Setting the two side by side shows where your choices are and where they are not.

A “panel” is the list of drug classes the lab looks for, and labs sell panels of different sizes. A wider panel catches more, and it also returns more results you have to handle with care: prescription drugs that show up legally, and in some states cannabis results you may not act on. Choose the panel for the job, write it into the policy, and give the same test to everyone in the role.

On-site instant cups give a fast screen, but a screen is not a confirmed result. Under DOT, only a lab confirmation verified by the MRO counts, and the MRO must give the employee the chance to show a legitimate medical explanation, such as a valid prescription, before verifying a positive. Copying that step into a company program is good practice: it is the step that stops you from withdrawing an offer over a lawful prescription.

Building your testing policy

Whatever you test for, write it down first. Minnesota will not let an employer test at all without a written policy, and DOT requires written materials for every covered driver. Even where no statute asks for one, a written policy is what lets you show that every applicant for a job got the same test at the same point in hiring, which helps you answer a discrimination claim. California's civil rights agency gives the example directly: requiring only applicants of one race or ethnicity to take a drug test violates its law.

If your drivers also need a driving record check, the MVR guide covers the record at hire and the yearly review. To compare screening firms by the industries they serve, including those that offer drug testing alongside background checks, see employment screening services by industry, or start from the PBSA-accredited screeners directory.

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