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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 #13-0125 ([URS Corporation] [Mr. Andrew N. Romach])

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

Interpretation Response Details

Response Publish Date:

Company Name: URS Corporation

Individual Name: Mr. Andrew N. Romach

Location State: NC Country: US

View the Interpretation Document

Response text:

July 31, 2013


Mr. Andrew N. Romach
Regulatory Compliance Manager
URS Corporation
1600 Perimeter Park Drive
Morrisville, NC 27560

Ref. No. 13-0125

Dear Mr. Romach:

This responds to your June 14, 2013 letter regarding a previous letter of interpretation 02-0120 dated October 18, 2002 (see enclosed) that summarized exceptions provided in §§ 173.150 and 173.220 of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).  Your questions are paraphrased and answered as follows:

Q1.  With regard to the paragraph citations to § 173.220 in Q1 and A1 of the letter, does letter of interpretation 02-0120 remain valid even though subsequent rulemakings have made changes to the paragraph citations?

A1.  Yes, although paragraph citations in § 173.220 have been changed by rulemaking, the content of the letter remains valid.  An internal combustion engine containing only residual flammable liquid fuel up to 500 mL (17 ounces) and that is transported by motor vehicle is not subject to any additional requirements of the HMR (see § 173.220(b)(1) and (h)(1)).

Q2.  Is a flammable liquid with a flash point greater than or equal to 38°C (100°F) that is contained in an aviation turbine engine with a capacity less than 119 gal (450 L) still eligible for exception from the HMR under § 173.150(f).

A2.  Yes.  In accordance with § 173.150(f), a flammable liquid (as defined in
§ 173.120) with a flash point greater than or equal to 38°C (100°F) that does not meet the definition of any other hazard class and that is transported by motor vehicle or rail (i.e., ground transportation) may be reclassed as a combustible liquid.  A combustible liquid in a non-bulk packaging transported by motor vehicle or rail is not subject to the HMR unless the material is a hazardous substance, a hazardous waste, or a marine pollutant.  

Note that the regulatory revision to the upper limit of the flash point range from 60.5°C (141°F) to 60°C (140°F) (see rulemaking HM-215I (December 26, 2006; 78596, 78631)) for defining a material as a flammable liquid has no bearing on the response.  The reclassification of a material as combustible is based on whether the flash point exceeds 38°C (100°F) and is transported by motor vehicle or rail (except when these means of transport are impractical). See §§ 173.120(b)(2) and 173.150(f)(1).

I hope this information is helpful.  If you have further questions, please contact this office.


Robert Benedict
Chief, Standards Development Branch
Standards and Rulemaking Division

Enclosure:  Letter of Interpretation 02-0120

173.220, 173.150

Regulation Sections

Section Subject
173.150 Exceptions for Class 3 (flammable and combustible liquids)
173.220 Internal combustion engines, vehicles, machinery containing internal combustion engines, battery-powered equipment or machinery, fuel cell-powered equipment or machinery