§FMCSR.com
Historical textIn force on Oct. 1, 2003Source: annual CFR editions 2001–2004

§ 40.93 What criteria do laboratories use to establish that a specimen is dilute or substituted?

Wording in the annual edition revised as of Oct. 1, 2001, superseded by the 2005 annual edition.

govinfo, 2003 edition ↗
Before Jan. 1, 2017 the record is one snapshot per annual CFR edition, revised as of October 1. This is the 2003 edition's wording. An amendment that took effect between Oct. 1, 2003 and Oct. 1, 2003 would not appear until the next edition, so check the citations below and the Federal Register for exact effective dates.
49 CFR § 40.93 — What criteria do laboratories use to establish that a specimen is dilute or substituted?. Text in force on October 1, 2003. This wording effective October 1, 2001 to October 1, 2005. Source: govinfo, 2003 edition, https://www.govinfo.gov/app/details/CFR-2003-title49-vol1/CFR-2003-title49-vol1-sec40-93. Retrieved from FMCSR.com, https://fmcsr.com/reg/40.93?asof=2003-10-01, on October 26, 2026. Unofficial compilation; verify against the official source.

(a) As a laboratory you must consider the primary specimen to be dilute if the creatinine concentration is less than 20 mg/dL and the specific gravity is less than 1.003, unless the criteria for a substituted specimen are met.

(b) As a laboratory you must consider the primary specimen to be substituted if the creatinine concentration is less than or equal to 5 mg/dL and the specific gravity is less than or equal to 1.001 or greater than or equal to 1.020.

Amendment history

5 distinct wordings on file since Oct. 1, 1996
  1. June 1, 2023 → presenteCFR, day-precisediff vs. previous
    [88 FR 27643, May 2, 2023]
  2. May 2, 2023 → June 1, 2023eCFR, day-precisediff vs. previous
    [69 FR 64867, Nov. 9, 2004]
  3. Oct. 1, 2005 → May 2, 2023annual editions 2005–2016diff vs. previous
    [69 FR 64867, Nov. 9, 2004]
  4. Oct. 1, 2001 → Oct. 1, 2005annual editions 2001–2004diff vs. previousviewing
  5. Oct. 1, 1996 → Oct. 1, 2001annual editions 1996–2000

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.