[Code of Federal Regulations] [Title 49, Volume 1] [Revised as of October 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 49CFR40.99] [Page 654] 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. 40.99 How long does the laboratory retain specimens after testing? (a) As a laboratory testing the primary specimen, you must retain a specimen that was reported with positive, adulterated, substituted, or invalid results for a minimum of one year. (b) You must keep such a specimen in secure, long-term, frozen storage in accordance with HHS requirements. (c) Within the one-year period, the MRO, the employee, the employer, or a DOT agency may request in writing that you retain a specimen for an additional period of time (e.g., for the purpose of preserving evidence for litigation or a safety investigation). If you receive such a request, you must comply with it. If you do not receive such a request, you may discard the specimen at the end of the year. (d) If you have not sent the split specimen to another laboratory for testing, you must retain the split specimen for an employee's test for the same period of time that you retain the primary specimen and under the same storage conditions. (e) As the laboratory testing the split specimen, you must meet the requirements of paragraphs (a) through (d) of this section with respect to the split specimen.