Drug Test Cutoff Levels
Concentration thresholds set by SAMHSA that determine whether a drug test specimen is reported as positive or negative.
Key Facts
- Two stages: initial immunoassay screen and GC-MS/LC-MS confirmation
- SAMHSA/DOT set federal cutoff levels for 5-panel testing
- Confirmation cutoffs are typically lower than screening cutoffs
- Employers may set lower cutoffs for non-DOT testing
Cutoff levels establish the minimum concentration of a drug or metabolite that must be present for a test to be reported as positive. SAMHSA sets mandatory cutoff levels for federal workplace testing. There are two levels: initial (immunoassay screening) and confirmatory (GC-MS or LC-MS/MS). For example, marijuana initial cutoff is 50 ng/mL, confirmatory is 15 ng/mL. Cocaine initial is 150 ng/mL, confirmatory is 100 ng/mL. These thresholds eliminate normal environmental exposure from triggering positive results.
Drug Testing Procedures Compared
Key procedural elements that ensure drug test integrity and accuracy.
| Type | What It Covers | Regulation | Key Requirement | If Violated |
|---|---|---|---|---|
| Chain of Custody | Specimen tracking | 49 CFR Part 40 | Unbroken documentation | Test may be invalidated |
| CCF Form | Collection documentation | 49 CFR Part 40 | Multi-part form for all DOT tests | Test cancelled |
| Split Specimen | Retest option | 49 CFR Part 40 | Bottle A (30 mL) + Bottle B (15 mL) | Test cancelled if B negative |
| Cutoff Levels | Positive/negative threshold | SAMHSA guidelines | Two-stage: screen then confirm | False positives/negatives |
Frequently Asked Questions
- What is the cutoff level for a drug test?
- A cutoff level is the minimum concentration of a drug or its metabolite that must be present for a specimen to be reported positive. For federally regulated (DOT) urine testing, SAMHSA sets the thresholds — for example, marijuana (THC) has a 50 ng/mL initial screening cutoff and a 15 ng/mL confirmatory cutoff, while cocaine is 150 ng/mL screening and 100 ng/mL confirmatory. A result below the cutoff is reported as negative, even if a trace amount is detected.
- Why are confirmation cutoffs lower than screening cutoffs?
- The initial immunoassay screen is designed to be sensitive and flag any presumptive positive. Confirmation by GC-MS or LC-MS/MS is far more specific, so a lower confirmatory cutoff can reliably distinguish a true positive from background or cross-reacting substances. A specimen must exceed both the screening and the confirmatory cutoff to be reported positive.
- Can an employer set its own cutoff levels?
- For DOT-regulated testing, no — the SAMHSA cutoff levels are mandatory and cannot be changed. For non-DOT (employer) programs, employers have more flexibility and may select lower cutoffs or expanded panels, subject to applicable state drug-testing laws.
Related Services
Related Industries
50
States Covered
Need This Service?
Find certified occupational health providers offering this service in your area. Over 20,000 locations nationwide.
Simplify Occupational Health
BlueHive manages occupational health services so you can focus on your workforce.