§ 40.86 What is urine validity testing, and are laboratories required to conduct it?

PART 40—PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS, last amended 2023-06-01

(a) Specimen validity testing is the evaluation of the specimen to determine if it is consistent with normal human urine. The purpose of validity testing is to determine whether certain adulterants or foreign substances were added to the urine, if the urine was diluted, or if the specimen was substituted.

(b) As a laboratory, you must conduct validity testing.

Official text from the eCFR. The eCFR is an authoritative but unofficial editorial compilation; the Federal Register is the legal source.