Certain employees in the transportation industry are subject to federal drug and alcohol use and testing regulations, under the federal Department of Transportation (DOT). An employee who violates these regulations must be immediately removed from safety-sensitive functions, and may not be returned to any safety-sensitive functions in the transportation industry until and unless he/she successfully completes a DOT return-to-duty process.

A positive test is a violation. So also is a refusal to be tested. So are a number of other things that are prohibited by DOT.

When an employee has a positive test or refuses to be tested or has one of DOT's other violations, DOT requires the employer to immediately remove that employee from safety-sensitive functions. An employer who allows an employee with a violation to continue performing safety-sensitive functions is subject to fines, up to $10,000 per day.

An employee who has a violation has two options.

1) He/she can find another job, outside of the transportation industry.

2) He/she can be considered for returning to safety-sensitive functions in the transportation industry, but only after successfully completing DOT’s return-to-duty process, and then providing a negative result on a return-to-duty drug and/or alcohol testing.

The return-to-duty process requires involvement of a qualified and trained Substance Abuse Professional, or a SAP.
The SAP must conduct a face-to-face clinical evaluation of the employee. DOT’s rule then requires the SAP to recommend treatment and/or education for the employee.
The SAP must send a report to the employer, specifying the SAP's recommendation for treatment and/or education.
The SAP must then monitor the employee’s progress in the recommended program of treatment and/or education.
When the SAP determines that the employee has made sufficient progress, the SAP will schedule a Follow-Up evaluation for the employee.
Based on that evaluation, the SAP will report to the employer that the employee has successfully complied with the SAP's recommendation (or that the employee has not complied.)
If the SAP reports that the employee has successfully complied with the recommendation, the employer will decide whether to arrange for a return-to-duty test for the employee. (The employer is not obligated to take the employee back.)
If the SAP reports that the employee has not successfully complied with the recommendation, the employer cannot return to the employee to safety-sensitive functions.
An employee who has not successfully complied with the SAP's recommendation may not return to safety-sensitive functions for any DOT employer until the SAP's recommendations have been fully met, and the employee is able to provide a negative return-to-duty test.