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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 #14-0058 ([Transportation Systems Solutions] [Mr. Peter Olsen])

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

Interpretation Response Details

Response Publish Date:

Company Name: Transportation Systems Solutions

Individual Name: Mr. Peter Olsen

Location State: IL Country: US

View the Interpretation Document

Response text:

Mr. Peter Olsen
Transportation Systems Solutions
318 Hampshire Lane
Crystal Lake, IL   60014

Ref. No. 14-0058

Dear Mr. Olsen:

This responds to your March 21, 2014 request for clarification on combustible liquid material under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask about classification of material to a more stringent classification and classification of a non-hazardous material as hazardous.

In your letter, you state you intend to reclassify and rename a combustible liquid (NA1993, Combustible liquid, PG III) as a flammable liquid (UN1993, Flammable liquid, PG III) material. It is your understanding that although § 173.150 authorizes an exception in order to reclassify a flammable liquid with a flashpoint at or above 100°F to a combustible, describing the material as flammable does not diminish the intent of the HMR and could provide a higher level of packaging protection and a higher level of emergency response in the event of an incident. In addition, you want to classify your product as combustible regardless of whether it meets the defining criteria of a hazardous material. You note your line of product sometimes meets the combustible liquid defining criteria and at other times does not. Your questions are paraphrased and answered below.

Q1. May I classify a combustible liquid as a flammable liquid?

A1. Section 173.150 provides an exception to reclass a flammable liquid to a combustible liquid under certain conditions. However, it is not required under the HMR that you use the exception. If the flash point of your material is greater than 140°F but less than 200°F and does not meet the definition of any other hazard class, it must be classed as a combustible for domestic transportation. If the flash point is greater than or equal to 100°F but less than 140°F and does not meet the definition of any other hazard class, it may be reclassed as a combustible. The materials you refer to should be classed and described according to defining criteria in § 173.120 and the shipper's knowledge of the material. Therefore, if the material meets the definition of a combustible liquid in § 173.120, then it should be classed and described as such, e.g., NA 1993, Combustible liquid, PG III.

Q2. For ease of shipment, may I classify a product that fluctuates above or below a flashpoint of 200°F as combustible regardless of the flashpoint?

A2. A material with a flash point greater than or equal to 200°F that does not meet the definition of any other hazard class, may not be shipped as a hazardous material. In accordance with § 171.2(k), no person may, by marking or otherwise, represent that a hazardous material is present in a package, container, motor vehicle, rail car, aircraft, or vessel if the hazardous material is not present. Therefore, you may not ship all batches of you product as combustible if the properties of the batches vary such that the product fluctuates between hazardous and non-hazardous material. It is the shipper's responsibility to properly class and describe a material as hazardous for transportation in commerce in accordance with § 173.22.

I hope this answers your inquiry. If you need additional assistance, please contact this office at 202-366-8553.


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

173.150, 173.120, 171.2(k), 173.22

Regulation Sections

Section Subject
171.2 General requirements
173.120 Class 3-Definitions
173.150 Exceptions for Class 3 (flammable and combustible liquids)
173.22 Shipper's responsibility