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DOT Rule 49 CFR Part 40 Section 40.123

Subpart G - Medical Review Officers and the Verification Process

§ 40.123 What are the MRO's responsibilities in the DOT drug testing program?

As an MRO, you have the following basic responsibilities:
(a) Acting as an independent and impartial “gatekeeper” and advocate for the accuracy and integrity of the drug testing process.
(b) Providing a quality assurance review of the drug testing process for the specimens under your purview. This includes, but is not limited to:
(1) Ensuring the review of the CCF on all specimen collections for the purposes of determining whether there is a problem that may cause a test to be cancelled (see §§40.19940.203 ). As an MRO, you are not required to review laboratory internal chain of custody documentation. No one is permitted to cancel a test because you have not reviewed this documentation;
(2) Providing feedback to employers, collection sites and laboratories regarding performance issues where necessary; and
(3) Reporting to and consulting with the ODAPC or a relevant DOT agency when you wish DOT assistance in resolving any program issue. As an employer or service agent, you are prohibited from limiting or attempting to limit the MRO's access to DOT for this purpose and from retaliating in any way against an MRO for discussing drug testing issues with DOT.
(c) You must determine whether there is a legitimate medical explanation for confirmed positive, adulterated, substituted, and invalid results from the laboratory.
(d) While you provide medical review of employees' test results, this part does not deem that you have established a doctor-patient relationship with the employees whose tests you review.
(e) You must act to investigate and correct problems where possible and notify appropriate parties (e.g., HHS, DOT, employers, service agents) where assistance is needed, (e.g., cancelled or problematic tests, incorrect results).
(f) You must ensure the timely flow of test results and other information to employers.
(g) You must protect the confidentiality of the drug testing information.
(h) You must perform all your functions in compliance with this part and other DOT agency regulations.
[as amended 82 FR 52245, November 13, 2017; 88 FR 27645, May 2, 2023]]