StacksVerified U.S. regulatory reference

49 CFR §40.91

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
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: