Post-accident: the triggers are fixed
Section 382.303 applies to a surviving driver who was performing safety-sensitive functions with respect to a commercial motor vehicle operating on a public road in commerce. Whether a test is required depends on what the accident involved and whether the driver was cited. 49 CFR 382.303(a)–(b)
| Type of accident | Citation to the CMV driver | Test required? |
|---|---|---|
| Human fatality | Not required | Yes, always |
| Bodily injury with immediate medical treatment away from the scene | Required | Only if the driver is cited |
| Disabling damage to any vehicle requiring a tow away | Required | Only if the driver is cited |
The citation has its own clock. For the alcohol test, the citation must be received within eight hours of the occurrence; for the controlled substances test, within 32 hours. 49 CFR 382.303(a)(2), (b)(2) A citation that arrives on day three does not revive a post-accident test.
Three situations are carved out entirely: an occurrence involving only boarding or alighting from a stationary vehicle, one involving only loading or unloading cargo, and one in a passenger car or multipurpose passenger vehicle unless it is carrying passengers for hire or placarded hazardous materials. 49 CFR 382.303(h)
Reasonable suspicion: the trigger is what you observe
Section 382.307 does not mention accidents. It requires a test when a supervisor or company official trained under §382.603 has reasonable suspicion based on specific, contemporaneous, articulable observations of the driver’s appearance, behavior, speech, or body odors. 49 CFR 382.307(a)–(c) The determination, the clocks, and the written record are covered in detail in the reasonable suspicion checklist and observation form.
Two consequences follow. A trained supervisor who observes signs of impairment after a minor fender-bender can order a reasonable suspicion test even though no post-accident test is required. And an untrained manager at a crash scene cannot order a reasonable suspicion test at all, no matter what they saw.
Side by side
| Reasonable suspicion | Post-accident | |
|---|---|---|
| What triggers it | Specific, contemporaneous, articulable observations of the driver’s appearance, behavior, speech, or body odors. An accident is not required. | The accident itself, when it meets one of the three triggers above. No observation of the driver is required. |
| Who makes the call | A supervisor or company official trained under §382.603. The person who decides may not conduct the alcohol test. | The employer, by applying the triggers. No training requirement attaches to that decision. |
| Alcohol test clock | Two hours from the determination to test or record why not; stop at eight hours and record the reasons. | Two hours from the accident to test or record why not; stop at eight hours and record the reasons. |
| Drug test clock | No fixed deadline in §382.307. Test promptly. | Stop attempts at 32 hours after the accident and record the reasons. |
| The driver meanwhile | Off safety-sensitive functions until an alcohol test reads below 0.02 or 24 hours have passed since the determination. | Must remain readily available for testing or may be deemed to have refused. Medical care is never delayed. |
| Required record | Written observations signed within 24 hours or before results are released, whichever is earlier. | Reasons any test was not administered within two, eight, or 32 hours; submitted to FMCSA on request. |
| Citation | 49 CFR 382.307 | 49 CFR 382.303 |
After a crash: which test, if any?
Was a commercial motor vehicle operating on a public road in commerce involved, and was the driver performing safety-sensitive functions with respect to it?
Yes: Continue to question 2.
No: Section 382.303 does not apply. Check whether a trained supervisor has observations that would support reasonable suspicion, and follow company policy.
Did the accident involve the loss of human life?
Yes: Post-accident alcohol and controlled substances tests are required whether or not the driver is cited. Start the two-hour, eight-hour, and 32-hour clocks now.
No: Continue to question 3.
Did anyone receive immediate medical treatment away from the scene, or was any vehicle towed because of disabling damage?
Yes: Continue to question 4.
No: No post-accident test is required. A trained supervisor may still order a reasonable suspicion test based on their own observations of the driver.
Did the driver receive a citation for a moving violation arising from the accident within eight hours (alcohol) or 32 hours (drugs)?
Yes: The post-accident test is required for the window that applies. Record the reasons for any test not administered in time.
When both apply
- Tow-away, no citation, odor of alcohol. No post-accident test is required. A trained supervisor who smells alcohol on the driver’s breath and hears slurred speech has reasonable suspicion and orders the test under §382.307, writing those observations down.
- Fatality, driver appears sober. The post-accident tests are required regardless. There is no reasonable suspicion determination to make, and none is needed.
- Injury crash, citation arrives at hour ten. The citation is outside the eight-hour window, so no post-accident alcohol test is required; it is inside 32 hours, so the post-accident controlled substances test is. A trained supervisor with contemporaneous observations could still have ordered a reasonable suspicion alcohol test at the scene.
Related guides
- Reasonable suspicion checklist and observation form: the signs, the clocks, and a free two-page PDF.
- When a driver refuses a reasonable suspicion test: what counts as a refusal and what the employer must do next.
- Who needs reasonable suspicion training: by DOT mode, with the edge cases.
Frequently asked questions
Can we use the police officer’s breath or blood test instead of our own post-accident test?
Yes, if two conditions are met. Under 49 CFR 382.303(g), a breath or blood alcohol test, or a urine controlled substances test, conducted by federal, state, or local law enforcement with independent authority satisfies the post-accident requirement when the test conforms to the applicable testing requirements and the employer actually obtains the results. If you cannot get the results, the requirement is not met.
The driver left the scene to get medical care. Is that a refusal?
No. 49 CFR 382.303(e) says nothing in the post-accident rule requires delaying necessary medical attention for injured people or prohibits a driver from leaving the scene to get assistance or emergency medical care. Outside those situations, a driver subject to post-accident testing must remain readily available for testing or may be deemed to have refused.
Our driver was in a crash in a company pickup. Does post-accident testing apply?
Part 382 covers drivers of commercial motor vehicles that require a CDL, and 49 CFR 382.303(h)(3) specifically excludes an occurrence in a passenger car or multipurpose passenger vehicle unless it is carrying passengers for hire or placarded hazardous materials. If the vehicle involved is not a covered commercial motor vehicle, the DOT post-accident rule does not apply, although company policy may.
Who decides that a post-accident test is required?
The employer, by applying the triggers in 49 CFR 382.303(a) and (b): a fatality, or an injury treated away from the scene or a tow-away where the driver receives a citation. No supervisor observation is needed and no supervisor training is required for that decision. A trained supervisor is required only for a reasonable suspicion determination under 382.307(c).
What do drivers have to be told in advance?
Under 49 CFR 382.303(f), the employer must give drivers the necessary post-accident information, procedures, and instructions before they operate a commercial motor vehicle, so they can comply with the rule after a crash. Most carriers put a wallet card or a page in the driver handbook with who to call, how long to stay available, and where testing happens.
What records do we keep when a post-accident test is late or never happens?
If an alcohol test is not administered within two hours of the accident, the employer must prepare and keep a record stating why; at eight hours the employer stops trying and keeps the same record. If a controlled substances test is not administered within 32 hours, the employer stops and keeps a record of the reasons. These records must be submitted to FMCSA on request (49 CFR 382.303(d)), and documents generated in connection with post-accident testing decisions are retained for at least two years under 382.401(b)(2) and (c)(1)(vi).
Sources
Every citation on this page was checked against the eCFR text in effect on October 30, 2026.
