[Code of Federal Regulations]
[Title 49, Volume 1]
[Revised as of October 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR40.93]

[Page 605]
 
                        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 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.