How Do the DER and C/TPA Roles Differ in DOT Testing?

The DER is an employee of the employer, and a C/TPA is a service agent. The definition of Designated Employer Representative (DER) in 49 CFR 40.3 states that "Service agents cannot act as DERs." Under 49 CFR 40.15(d), an employer must not permit a service agent to act as its DER, and 49 CFR 40.355(k) tells service agents that they "must not act as a DER."

Section 40.3 defines the DER as an employee authorized by the employer to take immediate action to remove employees from safety-sensitive duties, or cause them to be removed, and to make required decisions in the testing and evaluation processes. The DER also receives test results and other communications for the employer.

Section 40.355(k) states that a C/TPA may be responsible for transmitting information about test results to the employer, but it must not act on behalf of the employer in actions to remove employees from safety-sensitive duties. Under 40.345, a C/TPA may act as an intermediary for testing information only when the employer chooses that arrangement.

The rules for owner-operators and other self-employed individuals are covered in What Can a C/TPA Do for an Owner-Operator under DOT Rules?. For motor carriers, Learn Laws® offers FMCSA Designated Employer Representative Training, which covers the DER role under 49 CFR 40.3.

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