Reasonable Suspicion Testing

One of the most consequential — and most mishandled — testing situations in DOT programs. Here's exactly what's required, who can act, and how to do it right.

Critical Rule: The observations must be made by a supervisor or company official trained under §382.603 (§382.307(c)) — FMCSA’s wording is “supervisor or company official,” not supervisors alone. No training = no authority to refer. The person who determines that reasonable suspicion exists for an alcohol test must not conduct that test.

Reasonable suspicion testing is triggered when a trained supervisor or company official makes specific, contemporaneous, articulable observations of the employee’s appearance, behavior, speech or body odors. The timing rule is not the same for the two test types. Under FMCSA §382.307(d), alcohol testing is authorised only if the observations are made during, just preceding, or just after the period of the work day the driver must be in compliance. Controlled-substances reasonable suspicion carries no such window — §382.307(b) expressly allows the observations to include indications of the chronic and withdrawal effects of controlled substances. Do not apply the alcohol window to a drug determination. It is not based on a hunch — it must be based on documented, observable facts.

Supervisor Training Requirements

Before any supervisor can make a reasonable suspicion referral, they must complete the following training. The 60+60 requirement below comes from FMCSA §382.603 and is not a DOT-wide figure — FAA, FRA, FTA, PHMSA and USCG each set their own supervisor-training rules:

60 min Drug Use Indicators Physical signs, behavioral changes, and performance indicators associated with controlled substance use
60 min Alcohol Misuse Indicators Physical signs, behavioral changes, and performance indicators associated with alcohol misuse
Supervisor training must be documented and records kept. Training completion should be logged in the employee's supervisory file with the date, duration, and training provider noted.

What Supervisors Are Trained to Observe

Observations must be specific and contemporaneous — general concerns or past behavior alone are not sufficient.

Physical Appearance

  • Bloodshot or glazed eyes
  • Constricted or dilated pupils
  • Flushed face or unusual pallor
  • Tremors or unsteady movements
  • Odor of alcohol on breath

Behavior & Speech

  • Slurred or incoherent speech
  • Unusually agitated or combative
  • Disoriented or confused
  • Erratic or unusual behavior
  • Inability to follow instructions

Performance

  • Near-miss accidents or close calls
  • Inability to complete routine tasks
  • Inconsistent or dangerous driving
  • Unexplained performance decline

Body Odor & Other

  • Smell of marijuana or other substances
  • Presence of drug paraphernalia
  • Admission of use

What Happens After a Determination Is Made

1
Document observations — the deadline, and the better practiceThe regulatory deadline (FMCSA): §382.307(f) requires a written record of the observations, signed by the supervisor or company official who made them, within 24 hours of the observed behavior or before the test results are released, whichever is earlier. Best practice: write it immediately anyway — recollection degrades fast, and a contemporaneous note is far harder to challenge. That is our recommendation, not the legal deadline. Record what was seen, heard and smelled, with specific details and the time. A second supervisor should co-sign if available. This document is critical if the test is disputed.
2
Remove the employee from safety-sensitive dutyThree FMCSA situations, three different triggers — do not merge them. (1) The determination and the test (§382.307): making the determination sets the testing obligation; if the test is not given within 2 hours the employer records why, and after 8 hours attempts cease with reasons recorded (§382.307(e)(1)). (2) A result of 0.02–0.039 (§382.505): triggered by an actual test result, not by the determination — no safety-sensitive functions until the start of the next regularly scheduled duty period, and not less than 24 hours following administration of the test. (3) No test administered (§382.307(e)(2)): even without a test the driver must not perform safety-sensitive functions while under the influence of or impaired by alcohol as shown by behavioral, speech and performance indicators — until a test returns below 0.02 or 24 hours have elapsed since the determination; §382.307(e)(3) limits action taken on behaviour and appearance alone. So removal is not automatic on any alcohol determination — identify which situation you are in. For controlled substances, federal law does not impose a blanket “pending result” removal based on observed behaviour alone; many employers impose one under their own company authority, which FMCSA expressly permits. Know which of the two you are applying, and write it into your policy.
3
Arrange transportationBest practice (not a Part 40 or §382 mandate): do not let the employee drive themselves to the collection site. Arrange safe transport consistent with company policy and applicable state law. Get the employee to the collection site and back home if needed.
4
Conduct the test within required timeframesAlcohol: document the reason if not done within 2 hours, and cease attempts after 8 hours (§382.307(e)(1)). Drugs: §382.307 sets no deadline — the 32-hour figure people quote is the post-accident drug window (§382.303(b)(2)), not a reasonable-suspicion one. Send the employee as soon as practicable. If no alcohol test happens, the employee stays off safety-sensitive duty until a test reads below 0.02 or 24 hours pass (§382.307(e)(2)).
5
Keep all documentationThe supervisor's written observation record, referral paperwork, and test results must all be retained. These records are subject to audit and may be needed if the employee challenges the referral.
Collector's role: When a reasonable suspicion referral arrives at the collection site, the collector treats it like any other collection. The collector does not make judgments about whether the referral was warranted — that determination has already been made by the employer. Follow the standard collection procedure and document the reason for test as "Reasonable Suspicion" on the CCF.