§FMCSR.com
Historical textIn force on Oct. 1, 2000Source: annual CFR editions 1996–2000

§ 40.21 The drugs.

Wording first on file in the 1996 annual edition, superseded by the 2001 annual edition.

govinfo, 2000 edition ↗
Before Jan. 1, 2017 the record is one snapshot per annual CFR edition, revised as of October 1. This is the 2000 edition's wording. An amendment that took effect between Oct. 1, 2000 and Oct. 1, 2000 would not appear until the next edition, so check the citations below and the Federal Register for exact effective dates.
49 CFR § 40.21 — The drugs.. Text in force on October 1, 2000. This wording effective October 1, 1996 to October 1, 2001. Source: govinfo, 2000 edition, https://www.govinfo.gov/app/details/CFR-2000-title49-vol1/CFR-2000-title49-vol1-sec40-21. Retrieved from FMCSR.com, https://fmcsr.com/reg/40.21?asof=2000-10-01, on October 26, 2026. Unofficial compilation; verify against the official source.

(a) DOT agency drug testing programs require that employers test for marijuana, cocaine, opiates, amphetamines and phencyclidine.

(b) An employer may include in its testing protocols other controlled substances or alcohol only pursuant to a DOT agency approval, if testing for those substances is authorized under agency regulations and if the DHHS has established an approved testing protocol and positive threshold for each such substance.

(c) Urine specimens collected under DOT agency regulations requiring compliance with this part may only be used to test for controlled substances designated or approved for testing as described in this section and shall not be used to conduct any other analysis or test unless otherwise specifically authorized by DOT agency regulations.

(d) This section does not prohibit procedures reasonably incident to analysis of the specimen for controlled substances (e.g., determination of pH or tests for specific gravity, creatinine concentration or presence of adulterants).

Amendment history

4 distinct wordings on file since Oct. 1, 1996
  1. June 1, 2023 → presenteCFR, day-precisediff vs. previous
    [65 FR 79526, Dec. 19, 2000, as amended at 88 FR 27637, May 2, 2023]
  2. May 2, 2023 → June 1, 2023eCFR, day-precisediff vs. previous
  3. Oct. 1, 2001 → May 2, 2023annual editions 2001–2016diff vs. previous
  4. Oct. 1, 1996 → Oct. 1, 2001annual editions 1996–2000viewing

A new entry appears whenever the regulatory words change between government snapshots. Day-precise from the eCFR (2017 onward); before that, one snapshot per annual CFR edition (revised as of October 1). Bracketed citations are the Federal Register history printed with the section.