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 — First Part 40 published
• 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–Q)

Two new subparts (covering oral fluid testing) extend the structure — §40.35 and surrounding sections are the operational rules.

The Six Modal Agencies

• FMCSA — Federal Motor Carrier Safety Administration · 49 CFR Part 382 · CDL drivers (interstate & certain intrastate) operating CMVs > 26,001 lbs, > 16 passengers, or hauling placarded hazmat
• 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 operators, dispatchers, mechanics, security personnel
• PHMSA — Pipeline and Hazardous Materials Safety Administration · 49 CFR Part 199 · pipeline operators, hazmat transport ops personnel
• 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 in 2024)
• Post-accident criteria specific to that mode
• Mode-specific consequences and notification rules

Part 40 sets HOW the test is conducted. Both apply to every DOT test.

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. Screens with ASD or EBT only — no confirmations.
• HHS-Certified Lab — analyzes urine specimens. Initial immunoassay, then 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:

• ! Collector cannot be a same-pool safety-sensitive co-worker
• ! MRO cannot have a financial interest in the lab
• ! SAP cannot also be the MRO who verified the violation
• ! 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, by a BAT, using an Evidential Breath Testing device. Not included in the drug panel; not part of the lab process; not reviewed by the MRO. Different chain of documentation (the ATF rather than the CCF).

What About Marijuana?

State-legal marijuana use is not a valid MRO explanation. DOT explicitly takes the position that marijuana is federally illegal regardless of state law and that medical marijuana cards do not authorize positive test results to be downgraded. 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 — Removed from safety-sensitive duty for at least 8 hours; not a violation, not a positive test
• 0.04 or higher — Violation; mandatory removal, SAP referral, return-to-duty process

Initial vs. Confirmation

Initial tests are immunoassay screens — fast, 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. If B is negative or shows a different result, the test is cancelled.

What Counts as a Refusal — §40.191

• 1Failure to appear for a test within the time set by the employer
• 2Failure to remain at the testing site until the process is complete
• 3Failure to provide a urine specimen (without a valid medical reason — see shy bladder)
• 4Failure to permit a directly observed collection when required
• 5Failure to provide a sufficient breath sample without a valid medical reason
• 6Failure to take a second test when the collector or BAT instructs
• 7Failure to undergo a medical examination when required
• 8Failure to cooperate with any part of the testing process
• 9Verified adulterated or substituted result (by the MRO)
• 10Possessing or wearing a prosthetic / cheating device when required to undergo observed collection

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, psychologist, social worker, EAP professional, addiction counselor (NAADAC / IC&RC certified)
• Completed DOT-specific qualification training
• Passing an exam from a DOT-approved testing organization
• Continuing education every 3 years

What the Clearinghouse Is

The FMCSA Drug & Alcohol Clearinghouse is a federal database — launched January 6, 2020 — that records every DOT drug or alcohol violation by a CDL driver, plus their return-to-duty progress. 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 live Clearinghouse stats dashboard.

Part 40 Recordkeeping — §40.333

Modal Rule Adds On

The modal rule (FMCSA, FAA, etc.) requires additional records:

• 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