September 1, 2025
If you’re a Substance Abuse Professional (SAP), employer, or safety-sensitive employee, understanding the return-to-duty (RTD) test is essential. It’s not just another drug test—it’s a second chance. But there’s a lot of confusion about what it is, who’s responsible, and when it should happen.
Let’s clear it up.
A return-to-duty test is a DOT-required drug and/or alcohol test that must be conducted after an employee has violated DOT drug and alcohol regulations and has completed the SAP process. It is:
This test is not for employees returning from long-term leave, vacation, or medical absence. That’s a pre-employment or pre-duty test—not a return-to-duty test.
As a SAP, your job is to:
You do not:
That is the employer’s responsibility.
Here’s where it gets tricky. If an employee was terminated after a violation:
Until that negative RTD test is completed, the employee’s Clearinghouse record will show “Not Eligible for Safety-Sensitive Functions.”
If the RTD test is cancelled for any reason—lab error, collection issue, etc.—it must be repeated. A valid, negative result is required before the employee can return to duty.
The return-to-duty test is a critical checkpoint in the DOT process. As a SAP, your role is to guide the employee to the threshold—but it’s the employer who opens the door.
So remember: