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Interpretation Response #25-0095

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Soquel Creek Water District

Individual Name: Mr. David J. Terrazas

Location State: CA Country: US

View the Interpretation Document

Response text:

June 8, 2026

Mr. David J. Terrazas
Soquel Creek Water District
5180 Soquel Dr.
Soquel, CA  95073

Reference No. 25-0095

Dear Mr. Terrazas:

This is in response to your June 12, 2025 letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to placarding requirements. You ask whether government employees using government vehicles solely for non‑commercial activities are subject to placarding requirements under the HMR, which may trigger obligations under the California Vehicle Code?

No. As provided in § 171.1(d)(5), the HMR do not apply to the transportation of hazardous materials in a motor vehicle, aircraft, or vessel operated by a Federal, state, or local government employee solely for noncommercial Federal, state, or local government purposes. Therefore, a state agency—such as the Soquel Creek Water District—that transports hazardous materials for non-commercial purposes, using its own personnel and vehicles, is not engaged in transportation in commerce and thus is not subject to the requirements of the HMR, including placarding under Part 172, Subpart H.

Although state and local governments may establish requirements at fixed facilities, non-Federal placarding requirements that differ from those in the HMR may be preempted under 49 U.S.C. § 5125. Preemption determinations are made on a case-by-case basis and this Letter of Interpretation does not constitute a formal preemption determination. However, the absence of a determination under 49 CFR 107.209(d) concerning a specific state requirement does not imply that the requirement is—or is not—preempted under the Federal hazardous materials transportation law.

I hope this information is helpful. Please contact us if we can be of further assistance.

Sincerely,

Arthur Pollack
Acting Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

107.209(d) 171.1(d)(5)

Regulation Sections