Designated Employer Representative (DER): Role and Responsibilities in Drug Testing

What is a designated employer representative? A designated employer representative (DER) is the person an employer authorizes to manage its drug and alcohol testing program and to act on test results. Under U.S. Department of Transportation (DOT) rules, the DER is the employee who can immediately remove workers from safety-sensitive duties and who makes the required decisions in the testing and evaluation process. Non-DOT employers often assign a similar role, even if they use a different title.

This guide explains the DER’s responsibilities, who can serve in the role, how the DER works with service agents such as Medical Review Officers and third-party administrators, and best practices for doing the job well.

The DER in DOT Drug and Alcohol Testing

DOT’s testing procedures are set out in 49 CFR Part 40, which applies to employers regulated by agencies such as the Federal Motor Carrier Safety Administration, Federal Aviation Administration, Federal Railroad Administration, Federal Transit Administration and Pipeline and Hazardous Materials Safety Administration. Part 40 defines the DER as an employee authorized by the employer to take immediate action to remove employees from safety-sensitive duties and to make required decisions in the testing and evaluation processes. The DER also receives test results and other communications for the employer.

In practical terms, the DER is the employer’s point of contact for everything related to the testing program. The Department of Transportation’s Office of Drug and Alcohol Policy and Compliance (ODAPC) publishes guidance that DERs should know well.

Key DER Responsibilities

Acting on test results

When a Medical Review Officer reports a verified positive result, or when an employee refuses to test, the DER must remove the employee from safety-sensitive duties immediately. The DER does not interpret laboratory results; that is the MRO’s role. The DER acts on the verified result reported by the MRO.

Return to duty and follow-up

After a DOT violation, the employee must be referred to a Substance Abuse Professional (SAP), complete the recommended education or treatment, pass a return-to-duty test and complete follow-up testing. The DER coordinates the employer’s part of this process.

Reasonable suspicion and post-accident testing

The DER ensures that reasonable suspicion and post-accident tests are ordered when required and completed within the required time limits. Supervisors who make reasonable suspicion determinations must receive training required by their DOT agency. For example, FMCSA requires supervisors to receive at least 60 minutes of training on alcohol misuse and 60 minutes on controlled substances use.

Who Can Serve as a DER?

Under DOT rules, the DER must be an employee of the employer, because the role involves acting for the employer and removing employees from duty. Service agents such as collection sites, laboratories and MROs cannot serve as an employer’s DER. A limited exception exists for owner-operators and self-employed individuals, who may use a consortium or third-party administrator to perform certain DER functions.

Employers can appoint more than one DER, which is helpful for covering different shifts, locations or absences. Many employers designate a primary DER and one or more backups.

Qualities of an effective DER

• Has the authority to remove employees from duty without delay
• Is available during operating hours, or has trained backups
• Understands Part 40 and the employer’s own agency rules
• Can keep sensitive information confidential
• Is organized and comfortable managing records and deadlines

The DER and Service Agents

Employers rely on several service agents, and the DER is the link between them and the company.

The DER Role in Non-DOT Programs

Employers that are not regulated by DOT are not required to appoint a DER, but most effective programs assign the same responsibilities to a specific person. That person typically receives results, coordinates confirmation testing, applies the employer’s policy consistently and protects confidentiality. Non-DOT programs often use rapid on-site tests, so the program contact also oversees supplies, collector training and how preliminary results are handled. For the differences between program types, see our DOT vs non-DOT drug testing guide.

When non-DOT programs use instant test cups, the DER or program contact should ensure that non-negative screens are confirmed by a laboratory before any employment decision is made. Our CLIA-waived drug test cups are commonly used for this type of on-site screening.

A Typical DER Workflow After a Verified Positive

1. Receive the verified result from the MRO and confirm the employee’s identity and test details.
2. Remove the employee from all safety-sensitive functions immediately.
3. Provide SAP information, including names and contact details of qualified Substance Abuse Professionals, as required by the regulations.
4. Document every action, including dates, times and who was notified.
5. Coordinate return to duty once the SAP confirms compliance, including a directly observed return-to-duty test.
6. Schedule follow-up testing according to the SAP’s plan, keeping test dates unannounced.

Employers may also have reporting obligations to their agency’s clearinghouse or database. For example, FMCSA-regulated employers must report certain violations to the FMCSA Drug and Alcohol Clearinghouse. The DER typically owns or coordinates these reports.

Confidentiality and Records

DOT rules strictly limit who can receive employee testing information. The DER should share results only with people who need them to perform their duties, such as a supervisor who must take the employee off a route. Records should be kept separate from general personnel files, in a secure system with limited access. Retention periods vary by record type, from one year for negative results to five years for positive results and refusals, so DERs should keep a retention schedule and follow it.

Common DER Mistakes to Avoid

• Delaying removal from duty: Removal after a verified positive or refusal must be immediate.
• Acting on unverified results: In DOT testing, the DER acts on MRO-verified results, not laboratory reports or rumors.
• Sharing results too widely: Results should go only to people with a legitimate need to know.
• Losing track of follow-up testing: Follow-up tests must be unannounced and completed on the SAP’s schedule.
• No backup DER: Results and incidents can occur at any time, so coverage is essential.
• Poor recordkeeping: Missing records can lead to findings in audits and compliance reviews.

Best Practices for DERs

1. Keep an up-to-date written policy and make sure employees have received it.
2. Maintain a contact list for your MRO, collectors, SAPs and C/TPA.
3. Use a checklist for each test type so required steps are not missed.
4. Store records in a secure, access-controlled system.
5. Review ODAPC updates and agency guidance regularly.
6. Train backup DERs and supervisors on their roles.

Employers building or updating a program can also review our 2026 guide to workplace drug testing and our article on best practices for drug and alcohol testing.

Key Takeaway

The designated employer representative is the employer’s authorized point person for drug and alcohol testing. In DOT programs, the DER receives verified results, removes employees from safety-sensitive duty immediately when required, manages the return-to-duty process and keeps the program compliant. Non-DOT employers benefit from assigning the same responsibilities to a trained, accountable person.

This article is for general educational purposes and is not legal advice. Employers should consult the applicable DOT agency rules and legal counsel.

Frequently Asked Questions

What is a designated employer representative?

A designated employer representative (DER) is the employee authorized by an employer to receive drug and alcohol test results, remove employees from safety-sensitive duty when required and make required decisions in the testing process.

Who can be a DER?

Under DOT rules, the DER must be an employee of the employer. Service agents such as MROs and collectors cannot serve as an employer’s DER, with a limited exception for owner-operators who use a consortium or third-party administrator.

Can a company have more than one DER?

Yes. Employers can designate more than one DER to cover different shifts, locations or absences.

Does a DER need special training?

Part 40 does not set a specific DER certification, but DERs must understand DOT rules, and supervisors who make reasonable suspicion determinations must complete training required by their DOT agency.

Do non-DOT employers need a DER?

They are not required to, but most effective non-DOT programs assign the same responsibilities to a designated person.