June 11, 2025
For employees in safety-sensitive DOT roles, returning to duty after a drug testing violation is a careful and structured process. Employers using urine testing should have a standard operating procedure in place that prioritizes accuracy and compliance. One key recommendation is ensuring the employee achieves three consecutive negative tests before they take a Return to Duty Test. This blog explores why these tests matter, how employers should approach them, and why relying on proper data is essential.
When an employee tests positive for THC (or another prohibited substance), the nanograms detected decrease over time. For instance, if an employee starts with 500 nanograms of THC, their levels may still exceed the 15-nanogram confirmation cutoff weeks later. Regular testing spaced out by five days ensures the employee’s system is clear before undergoing the official DOT Return to Duty Test.
Without proper preparation, employees are at a much higher risk of testing positive during their DOT Return to Duty Test, which could lead to further delays, compliance issues, and workplace complications.
Employers should request tests that align with DOT cutoff levels, even if the tests are not official DOT tests. This approach provides valuable data about the employee’s progress and readiness for the next step.
Employers should never declare an employee eligible for a Return to Duty Test if they lack supporting data, such as results from a treatment program or independent testing.
If you have no recent test data, recommend that the employee undergo testing at an independent clinic (paid out of pocket). For example, many Achmed clinics provide non-DOT testing services at reasonable costs, which can offer clarity about the employee’s progress.
Some education programs may not include drug testing as part of their services. Employers should request independent testing results from employees in such programs to ensure transparency.
Key Point: Employers cannot require employees to pay for tests. However, encouraging out-of-pocket testing serves as a safeguard to prevent false readiness for official DOT tests.
Ensure three consecutive negative tests are spaced out by at least five days to confirm that THC levels have consistently dropped below DOT cutoff levels.
Employees should be aware that CBD is not a valid defense for a positive THC result. DOT does not test for CBD directly—any positive result reflects THC.
When training employees on DOT policies, highlight that CBD stands for “Can Be Discharged,” emphasizing the risk of THC contamination in CBD products.
Incorporate the requirement for consecutive negative tests into your company’s policy to maintain consistency and compliance.
The Return to Duty Test is a critical step in ensuring safety-sensitive employees are fit to resume their roles. By requiring three consecutive negative tests before proceeding, employers can prevent compliance issues and ensure a smoother process for everyone involved.
For Employers: Use proper testing protocols to safeguard your workplace and avoid unnecessary risks.
For Employees: Prepare responsibly for your Return to Duty Test and stay informed about how DOT policies affect your role.
Need help refining your company’s drug testing procedures or educating employees on best practices? Let me know how I can assist.
Karishma is a Qualified Substance Abuse Professional (SAP) with a background in mental health and substance abuse counseling, holding credentials as an MS, LCDC, ICADC, CADC II, CSAC, CASAC II, LPC, and EMDR-trained therapist. Inspired by personal experiences with addiction and mental health challenges in her community, she has dedicated her career to supporting individuals on their journey to recovery and success.
