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DOT Rule 49 CFR Part 40 Section 40.201

Subpart I—Problems in Drug Tests

§ 40.201 What problems always cause a drug test to be cancelled and may result in a requirement for another collection?

 
As the MRO, you must cancel a drug test when a laboratory reports that any of the following problems have occurred. You must inform the DER that the test was cancelled. You must also direct the DER to ensure that an additional collection occurs immediately, if required by the applicable procedures specified in paragraphs (a) through (e) of this section.
 
(a) The laboratory reports an “Invalid Result.” You must follow applicable procedures in §40.159 (recollection under direct observation may be required).
 
(b) The laboratory reports the result as “Rejected for Testing.” You must follow applicable procedures in §40.161 (a recollection may be required).
 
(c) The laboratory reports that the split specimen failed to reconfirm all of the primary specimen results because the drug(s)/drug metabolite(s) were not detected; adulteration criteria were not met; and/ or substitution criteria were not met. You must follow the applicable procedures in § 40.187(b) – no recollection is required in this case, unless the split specimen creatinine concentration for a substituted primary specimen was greater than or equal to 2mg/dL but less than or equal to 5mg/ dL, or the primary specimen had an invalid result which was not reported to the DER. Both these cases require recollection under direct observation.
 
(d) The laboratory reports that the split specimen failed to reconfirm all of the primary specimen results, and that the split specimen was invalid. You must follow the procedures in § 40.187(c)(1) – recollection under direct observation is required in this case.
 
(e) The laboratory reports that the split specimen failed to reconfirm all of the primary specimen results because the split specimen was not available for testing or there was no split laboratory available to test the specimen. You must follow the applicable procedures in § 40.187(e) – recollection under direct observation is required in this case.
 
(f) The examining physician has determined that there is an acceptable medical explanation of the employee's failure to provide a sufficient amount of specimen. You must follow applicable procedures in §40.193(d)(1)(no recollection is required in this case).
 
[65 FR 79526, Dec. 19, 2000, as amended at 73 FR 35974, June 25, 2008; 88 FR 27648, May 2, 2023]