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Federal regulations · Through 2026-08-25 · Newer source version available

49 CFR 40.91: What are the cutoff concentrations for oral fluid drug tests?

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Where this section sits in the code
  1. Title 49—Transportation
  2. Subtitle A—Office of the Secretary of Transportation
  3. PART 40—PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS
  4. Subpart F—Drug Testing Laboratories

As a laboratory, you must use the cutoff concentrations displayed in the following table for initial and confirmatory drug tests for oral fluid specimens. All cutoff concentrations are expressed in nanograms per milliliter (ng/mL). The table follows:

Table 1 to § 40.91—Oral Fluid Testing Cutoff Concentrations

Initial test analyte Initial test cutoff 1 Confirmatory test analyte Confirmatory test cutoff concentration

Marijuana (THC) 2 4 ng/mL 3 THC 2 ng/mL.

Cocaine/Benzoylecgonine 15 ng/mL Cocaine Benzoylecgonine 8 ng/mL. 8 ng/mL.

Codeine/Morphine 30 ng/mL Codeine Morphine 15 ng/mL. 15 ng/mL.

Hydrocodone/Hydromorphone 30 ng/mL Hydrocodone Hydromorphone 15 ng/mL. 15 ng/mL.

Oxycodone/Oxymorphone 30 ng/mL Oxycodone Oxymorphone 15 ng/mL. 15 ng/mL.

6-Acetylmorphine 4 ng/mL 3 6-Acetylmorphine 2 ng/mL.

Phencyclidine 10 ng/mL Phencyclidine 10 ng/mL.

Amphetamine/Methamphetamine 50 ng/mL Amphetamine Methamphetamine 25 ng/mL. 25 ng/mL.

MDMA 4/MDA 5 50 ng/mL MDMA MDA 25 ng/mL. 25 ng/mL.

1 For grouped analytes (i.e., two or more analytes that are in the same drug class and have the same initial test cutoff):

Immunoassay: The test must be calibrated with one analyte from the group identified as the target analyte. The cross reactivity of the immunoassay to the other analyte(s) within the group must be 80 percent or greater; if not, separate immunoassays must be used for the analytes within the group.

Alternate technology: Either one analyte or all analytes from the group must be used for calibration, depending on the technology. At least one analyte within the group must have a concentration equal to or greater than the initial test cutoff or, alternatively, the sum of the analytes present (i.e., with concentrations equal to or greater than the laboratory's validated limit of quantification) must be equal to or greater than the initial test cutoff.

2 An immunoassay must be calibrated with the target analyte.

3 Alternate technology (THC and 6-AM): The confirmatory test cutoff must be used for an alternate technology initial test that is specific for the target analyte (i.e., 2 ng/mL for THC, 2 ng/mL for 6-AM).

4 Methylenedioxymethamphetamine (MDMA).

5 Methylenedioxyamphetamine (MDA).

Collected 2026-08-27T02:26:34Z. Source file · JSON

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