The Origin Story

• 11986 — Reagan EO 12564 — Drug-Free Federal Workplace order
• 21988 — HHS Mandatory Guidelines — published the first urine drug testing standards (the basis for SAMHSA-certified labs)
• 31991 — Omnibus Transportation Employee Testing Act — passed in the aftermath of safety incidents involving impaired transportation workers; mandated DOT to publish testing rules
• 41994 — major alcohol-testing expansion (DOT drug procedures date to 1988)
• 52000s — Refinements — observed collections, oral fluid considered, MRO rules clarified
• 62018 — Opioid expansion — added oxycodone, oxymorphone, hydrocodone, hydromorphone (semi-synthetics)
• 72020 — FMCSA Clearinghouse launched
• 82023 — Oral fluid authorized as a DOT testing method (§40.35)

Subpart Structure (A—R)

Part 40 runs A through R. Oral fluid testing did not add new subparts — it was integrated into the existing ones (Subpart D is now “…Used in DOT Urine and Oral Fluid Testing”), with §40.72–§40.74 carrying the oral fluid operational rules (§40.35 covers collector qualification).

The Six Modal Agencies

• FMCSA — Federal Motor Carrier Safety Administration · 49 CFR Part 382 · CDL drivers (interstate & certain intrastate) operating CMVs with a gross vehicle or gross combination weight rating of 26,001 pounds or more, vehicles designed to transport 16 or more passengers, including the driver, or a vehicle of any size carrying hazardous materials that require placarding under 49 CFR part 172, subpart F (§382.107)
• FAA — Federal Aviation Administration · 14 CFR Part 120 · pilots, flight attendants, mechanics, dispatchers, ATC, ground security coordinators
• FRA — Federal Railroad Administration · 49 CFR Part 219 · engineers, conductors, dispatchers, signal maintainers
• FTA — Federal Transit Administration · 49 CFR Part 655 · public transit vehicle operators, controllers/dispatchers, maintenance personnel, and personnel carrying a firearm for security purposes (§655.4) — security staff who do not carry a firearm for security purposes are not covered on that basis alone
• PHMSA — Pipeline and Hazardous Materials Safety Administration · 49 CFR Part 199 · employees performing operations, maintenance or emergency‑response functions regulated by 49 CFR parts 192, 193 or 195 and performed on a pipeline or an LNG facility (§199.3)
• USCG — U.S. Coast Guard · 46 CFR Part 16 · commercial mariners on inspected vessels and certain uninspected commercial vessels

Mode-Specific vs. Part 40

The modal rule sets:

• WHO must be tested (which job categories are "safety-sensitive")
• Random testing rates (e.g., FMCSA: 50% drug, 10% alcohol for 2026 — FMCSA sets the minimum annually, so confirm the current year’s rate)
• Post-accident criteria specific to that mode
• Mode-specific consequences and notification rules

Part 40 sets HOW the test is conducted. Both apply together for the DOT tests Part 40 governs — note that Coast Guard marine-employer alcohol testing runs under its own maritime rules, not Part 40’s alcohol provisions.

The Six Reasons

Reasonable Suspicion Documentation

Every RS test should be backed by a written record listing the supervisor's observations. Without it, the determination can be challenged. Templates and the supervisor training requirement are covered separately on the Reasonable Suspicion resource page.

The Cast

• Employer — ultimately responsible for the testing program. Cannot delegate liability, even when using a C/TPA.
• DER (Designated Employer Representative) — the employer's named contact for testing. Receives results, handles refusals, makes employment decisions. Identified to the collector / BAT on the CCF or ATF.
• Collector — qualified under §40.33 (urine) or §40.35 (oral fluid). Performs the collection and chain of custody.
• BAT (Breath Alcohol Technician) — qualified under §40.213. Operates the EBT and conducts the full alcohol test.
• STT (Screening Test Technician) — limited credential. Under §40.3 an STT operates an ASD — a breath or saliva screening device other than an EBT. Screening only; an STT does not conduct confirmation tests and is not an EBT operator.
• HHS-Certified Lab — analyzes specimens. Initial testing uses an authorized method — immunoassay or a permitted alternate technology (§40.85) — followed by GC/MS or LC/MS confirmation. Sends results to the MRO, not directly to the employer.
• MRO (Medical Review Officer) — licensed physician with specific training. Reviews non-negative lab results, interviews the donor about possible legitimate medical explanations, verifies the result, and reports to the DER.
• SAP (Substance Abuse Professional) — qualified counselor / clinician. Evaluates employees after violations, prescribes treatment, signs off on return-to-duty eligibility.
• C/TPA (Consortium / Third-Party Administrator) — administers programs for groups of employers. Manages random selections, scheduling, recordkeeping. The employer is still legally responsible.
• Donor / Employee — the person being tested. Has rights (privacy, split specimen test, refusal to consent has consequences but is not "criminal").
• Service Agent (Subpart Q) — umbrella term for everyone the employer outsources to. Subject to DOT enforcement directly.

Conflict-of-Interest Rules

No one can play roles that create a conflict. Examples:

• ! §40.31 bars three things: the employee’s immediate supervisor collecting (unless no other collector is available and the DOT agency rule permits), HHS-lab staff who could link employee to result, and self-collection. Avoiding same-pool co-worker collections is good practice, not a stated prohibition
• ! MRO cannot have a financial interest in the lab
• ! SAP and MRO roles are kept separate as a conflict-avoidance practice — but note that Part 40 does not contain a provision barring the MRO who verified the violation from also acting as the SAP. Do not teach that as a regulatory prohibition. What Part 40 does say is that neither the SAP nor the MRO may make a “fitness for duty” determination as part of the re-evaluation unless an applicable DOT agency regulation requires it (§40.305(c))
• ! Collector / BAT cannot be the donor's direct supervisor (with limited exceptions)

The Federal 5-Panel (Post-2018)

• Marijuana metabolites (THCA)
• Cocaine metabolites (benzoylecgonine)
• Opioids — codeine, morphine, 6-AM (heroin marker), plus hydrocodone, hydromorphone, oxycodone, oxymorphone (the 2018 additions)
• Amphetamines — amphetamine, methamphetamine, MDMA, MDA
• Phencyclidine (PCP)

The 2018 Opioid Expansion

Before 2018, the opiate panel only tested for codeine, morphine, and heroin metabolite. The 2018 rule recognized the prescription-opioid crisis and added the four semi-synthetic opioids — bringing the panel in line with how opioid abuse actually looks in 2018+. The panel section was renamed from "Opiates" to "Opioids."

Alcohol

Alcohol is tested separately from the drug panel — not part of the lab process, not reviewed by the MRO, and documented on the ATF rather than the CCF. Be precise about who does what: the screening test may be conducted by an STT or a BAT, using an ASD — which §40.3 defines as a breath or saliva device other than an EBT — or using an EBT. The confirmation test is different: it is performed only by a BAT, and only on an EBT (§40.3, §40.251). So "a BAT using an EBT" describes the confirmation test, not every DOT alcohol test.

What About Marijuana?

State-legal marijuana use is not a valid MRO explanation. The conclusion is settled; teach the current mechanism rather than a general statement about federal illegality. A legitimate medical explanation under Part 40 rests on a legally valid prescription consistent with the Controlled Substances Act — that is the express test in §40.137(a) and §40.141(b). A state medical-marijuana card, physician certification or dispensary receipt is not a legally valid prescription for an FDA-approved controlled substance, so it cannot satisfy that standard. DOT confirmed this framing in its updated guidance of 15 May 2026 addressing the rescheduling change — the outcome did not move, but the reasoning is now the prescription test rather than the Schedule I label. (§40.151(e) still independently bars verifying negative on a physician’s recommendation to use a Schedule I drug.) §40.151(f) separately bars the MRO from accepting an assertion of hemp or other non-prescription marijuana-product use as a basis for verifying a marijuana test negative. CBD products that contain THC can also produce positive tests — products labeled "THC-free" sometimes aren't.

Drug Cutoffs (ng/mL)

Cutoffs are the trigger thresholds — below cutoff is reported as negative even if the drug is detectable.

Alcohol Thresholds

• < 0.02 — Negative; no further action
• 0.02 — 0.039 — Not a violation and not a positive test, but the employee is removed from safety-sensitive duty. The length is set by the MODE, not by Part 40: FMCSA is the next duty period but not less than 24 hours (§382.505(a)); FTA is the next duty period but not less than 8 hours (§655.35). Check your mode — quoting 8 hours to a motor carrier puts a driver back 16 hours early
• 0.04 or higher — Violation; mandatory removal, SAP referral, return-to-duty process

Initial vs. Confirmation

Initial tests use an authorised initial-test technology — an immunoassay or a permitted alternate technology (§40.85) — fast and sensitive, but susceptible to cross-reactivity. Confirmation is GC/MS or LC/MS — molecularly specific. A specimen must pass both cutoffs to be reported positive. That two-tier requirement protects against false positives from cross-reactive substances (poppy seeds, certain cold medicines, etc.).

The Chain

Split Specimen

Every DOT urine collection is a split. Bottle A is tested. Bottle B is held at the lab. A donor who disputes a verified positive can request — within 72 hours of being notified by the MRO — that bottle B be tested at a different HHS-certified lab. What happens next depends on the specific original/split combination — §40.187 sets a different MRO action for each. Some outcomes cancel the test, some change the verified result, and some require a recollection under direct observation. “Different result = cancelled” is too broad.

What Counts as a Refusal — §40.191

• 1Fail to appear for any test except a pre-employment test, within a reasonable time set by the employer (§40.191(a)(1))
• 2Fail to remain at the testing site until the process is complete — but an employee who leaves before the testing process commences for a pre-employment test has not refused (§40.191(a)(2))
• 3Fail to provide a specimen, with the same pre-employment carve-out (§40.191(a)(3))
• 4In a directly observed or monitored urine collection, fail to permit the observation or monitoring (§40.191(a)(4))
• 5Fail to provide a sufficient amount of specimen where the required medical evaluation found no adequate medical explanation (§40.191(a)(5))
• 6Fail or decline to take an additional drug test the employer or collector directed (§40.191(a)(6))
• 7Fail to undergo a medical examination or evaluation as directed (§40.191(a)(7))
• 8Fail to cooperate with any part of the testing process — e.g. refusing to empty pockets, disruptive behaviour, refusing to wash hands, refusing to remove objects from the mouth or permit oral inspection (§40.191(a)(8))
• 9For an observed urine collection, fail to follow the observer’s instructions to raise clothing above the waist, lower clothing and underpants, and turn around (§40.191(a)(9))
• 10Possess or wear a prosthetic or other device that could be used to interfere with the collection (§40.191(a)(10))
• 11Admit to the collector or MRO that you adulterated or substituted the specimen (§40.191(a)(11))

Consequences of Refusal

A refusal carries the same consequences as a verified positive: immediate removal from safety-sensitive functions, SAP evaluation, and a return-to-duty process. The Clearinghouse records refusal events the same as positive results.

What's NOT a Refusal

• Genuinely insufficient specimen at the start of a shy-bladder protocol (start the 3-hour clock)
• Refusal to sign Step 5 of the CCF (note in Remarks; collection still complete)
• Delay due to a legitimate emergency that the employer authorizes

The Post-Violation Process

Who Qualifies as a SAP

• Licensed physician (MD or DO); licensed or certified psychologist; licensed or certified social worker; licensed or certified employee assistance professional; state-licensed or certified marriage and family therapist; or a drug and alcohol counselor certified by an organization on the ODAPC list (§40.281(a))
• Completed DOT-specific qualification training
• Passing an examination administered by a nationally-recognized professional or training organization (§40.281(c)(2)) — DOT does not approve SAP testing organizations
• Continuing education every 3 years

What the Clearinghouse Is

The FMCSA Drug & Alcohol Clearinghouse is a federal database — launched January 6, 2020 — that records drug and alcohol program violations for drivers subject to FMCSA Part 382 — that is, drivers performing safety-sensitive functions on vehicles requiring a CDL — plus their return-to-duty progress. Holding a CDL does not by itself put a person’s every activity into the Clearinghouse; the driver must be covered by Part 382 and the event must be a defined reportable event. It exists because before 2020, a driver who violated for one employer could simply leave and apply elsewhere — and the new employer had no way to find out.

Three Things Employers Do

By the Numbers

The Clearinghouse has been live since 2020 — the live counts of violations, queries, and return-to-duty progress are publicly visible. See our .

Part 40 Recordkeeping — §40.333

Modal Rule Adds On

§40.333 does not cover everything. Random-selection records, collector and BAT qualification files, supervisor-training records and policy acknowledgments are retained under the applicable modal rule (e.g. FMCSA §382.401), not under §40.333. Check the mode before quoting a period:

• Supervisor training records (reasonable suspicion)
• Driver / employee policy acknowledgments
• Annual MIS (Management Information System) summary reports (when requested)
• Clearinghouse query records (FMCSA only)

What an Auditor Will Ask For

• ? Written drug & alcohol policy + signed acknowledgments
• ? Random selection records — last 2 years
• ? A sample of test records covering each reason for testing
• ? Supervisor training records for everyone supervising safety-sensitive employees
• ? Pre-employment query & annual query records (FMCSA)
• ? Refusal handling and Clearinghouse reports for any violations