[Code of Federal Regulations]
[Title 49, Volume 1]
[Revised as of October 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR40.93]

[Page 615-616]
 
                        TITLE 49--TRANSPORTATION
 
          Subtitle A--Office of the Secretary of Transportation
 
PART 40_PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING 
PROGRAMS--Table of Contents
 
                   Subpart F_Drug Testing Laboratories
 
Sec.  40.93  What criteria do laboratories use to establish that a specimen 
is dilute or substituted?

    (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

[[Page 616]]

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.