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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #23-0012

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

Interpretation Response Details

Response Publish Date:

Company Name: Kansas Highway Patrol

Individual Name: Technical Trooper Nick Wright

Location State: KS Country: US

View the Interpretation Document

Response text:

September 29, 2023

Technical Trooper Nick Wright, K-100
Kansas Highway Patrol
Troop I, Commercial Vehicle Enforcement
1220 S. Enterprise
Olathe, KS  66061

Reference No. 23-0012

Dear Mr. Wright:

This letter is in response to your February 15, 2023, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to shipping papers that describe hazardous materials and materials not subject to the requirements of the HMR. You ask about a scenario in which a shipping paper describes both fully regulated hazardous materials and a hazardous material that is not subject to regulation—including not subject to shipping paper requirements—when transported by motor vehicle. Specifically, you provide a scenario of a shipping paper for motor vehicle transportation that lists and describes the following materials in this order: "UN1090, Acetone, 3, PG II"; "UN1845, Carbon dioxide, solid, 9"; and "UN1263, Paint, 3, PG II" and includes an "HM" to distinguish hazardous material from non-hazardous material.

We have paraphrased and answered your questions as follows:

Q1. You ask, as provided in § 172.201(a)(1) for preparation of shipping papers, whether the "UN1845, Carbon dioxide, solid, 9" should be distinguished from the regulated hazardous materials (e.g., by placing an "X" in the "HM" column for the other two materials) given that it is only regulated as a hazardous material by air or vessel transportation, and not for shipment by motor vehicle.

A1. PHMSA is unable to provide a definitive response in the absence of additional necessary information about the way the material is transported. That said, in the § 172.101 Hazardous Materials Table, "UN1845, Carbon dioxide, solid or Dry ice" is assigned an "A" and a "W" in Column 1 indicating the material is only regulated when transported by aircraft or vessel. Moreover, in accordance with § 172.101(b)(2) and (6), a shipping description entry preceded by a "A" or "W", respectively, may be used to describe a material for other modes of transportation provided all applicable requirements for the entry are met (emphasis added). Thus, for motor vehicle only transportation one may not use the description "UN1845, Carbon dioxide, solid" unless meeting all requirements of the HMR. Note that for multi-modal transportation, § 172.201(a)(1) would not apply to shipping papers for the motor vehicle portion of transportation in association with aircraft or vessel transportation.

Q2. You ask whether the answer would change if the shipping paper simply listed "dry ice" instead.

A2. The answer is yes. For motor vehicle-only transportation, simply listing "dry ice" between the descriptions of the hazardous materials would result in § 172.201(a)(1) applying and necessitating either: the use of a contrasting color for any description on the shipping paper pertaining to a material that is not subject to the requirements of the HMR or adding an "X" in the "HM" column for the two hazardous materials in the example you provide.

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


Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

172.101, 172.201(a)(1), 172.101(b)(2) and (6)

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
172.201 Preparation and retention of shipping papers