[Code of Federal Regulations]

[Title 49, Volume 1]

[Revised as of October 1, 2005]

From the U.S. Government Printing Office via GPO Access

[CITE: 49CFR40.91]



[Page 652]

 

                        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. 40.91  What validity tests must laboratories conduct on primary 

specimens?



    As a laboratory, when you conduct validity testing under Sec. 

40.89, you must conduct it in accordance with the requirements of this 

section.

    (a) You must determine the creatinine concentration on each primary 

specimen. You must also determine its specific gravity if you find the 

creatinine concentration to be less than 20 mg/dL.

    (b) You must determine the pH of each primary specimen.

    (c) You must perform one or more validity tests for oxidizing 

adulterants on each primary specimen.

    (d) You must perform additional validity tests on the primary 

specimen when the following conditions are observed:

    (1) Abnormal physical characteristics;

    (2) Reactions or responses characteristic of an adulterant obtained 

during initial or confirmatory drug tests (e.g., non-recovery of 

internal standards, unusual response); or

    (3) Possible unidentified interfering substance or adulterant.

    (e) If you determine that the specimen is invalid and HHS guidelines 

direct you to contact the MRO, you must contact the MRO and together 

decide if testing the primary specimen by another HHS certified 

laboratory would be useful in being able to report a positive or 

adulterated test result.



[65 FR 79526, Dec. 19, 2000, as amended at 69 FR 64867, Nov. 9, 2004]