Part 40 Final Rule – Oral Fluid Testing

If you’re working in a DOT regulated industry, you’ve probably heard a lot about Part 40 recently. But what does it really mean for employees and employers and when does it take effect? We’re here to help.

For employees, the main change is that you may now be subject to either an oral fluid or urine collection for any DOT-regulated test for any reason (i.e., pre-employment, random, reasonable suspicion, post-accident, return-to-duty, or follow-up). Your employer will have the choice of which collection should be conducted and, if a second collection is necessary during the testing event (ex., out of range temperature, insufficient quantity), your employer may choose to change to the other type of collection at that time.

For employers, as stated above, you determine which method of collection should be conducted for the test reason. However, if you’re planning to use oral fluid testing, first and foremost you will need to update your drug testing policy, provide a copy of the policy change to your employees, and have employees sign off on their understanding of this policy change. Your legal team should be consulted when updating any legally binding documents.

While this has always been best practice, it’s especially important now that test type can change, but we recommend that you ensure your current phone number is always listed on the chain of custody form so the collector can reach you if there are problems during the collection. Yes, Designated Employer Representatives (DERs) have always been required to be available to collectors 24/7, but these changes make it even more imperative.

Best Practices for DERs

  • List the correct phone number on every chain of custody form (CCF).
  • Create a business relationship with your collection site and discuss standing orders on the type of test you want conducted during a problem scenario.
  • Be available to speak with collectors to discuss problems during collections, especially if no standing order is in place.

It’s also valuable to note that Medical Review Officers (MROs) are not being required to undergo recertification training for oral fluid testing but rather being strongly advised to seek supplemental information prior to this new regulated testing becoming available. So, when will that be? While the final rule in the Federal Register (88 FR 27596) was published on May 2nd, 2023, it will not be effective until around June 1, 2023, as time is needed for the Department of Health and Human Services to certify at least two laboratories. The first laboratory will serve as primary with the second serving as a split specimen.

Other Changes to Part 40

  • Oral fluid collections must be conducted for direct observation collections involving transgender or nonbinary individuals.
  • For direct observation collections, if the same gender cannot be present:
    • The employer may set up a standing order to allow oral fluid testing in such situations.
    • If there is no standing order, the collector must contact the DER to inquire about performing either an oral fluid collection or sending the sending the employee to another collection site that can better assist.

Remember, it is the employer’s responsibility to determine if a refusal has occurred at the collection site – this rule has not changed. If an employee does not appear for a pre-employment drug test or leaves the collection site before receiving a cup (urine testing) or unwrapping the device (oral fluid testing), it is not a refusal.

Do you plan on utilizing oral fluid testing? Let us know in the comments or email us at

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