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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 #10-0265 ([Minnesota Department of Transportation] [Mr. Michael Ritchie])

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

Interpretation Response Details

Response Publish Date:

Company Name: Minnesota Department of Transportation

Individual Name: Mr. Michael Ritchie

Location State: MN Country: US

View the Interpretation Document

Response text:

January 18, 2011





Mr. Michael Ritchie

Hazardous Materials Specialist

Minnesota Department of Transportation

Office of Freight & Commercial Vehicle Operations

395 John Ireland Boulevard, Mail Stop 460

St. Paul, MN 55155-1899

Ref. No. 10-0265

Dear Mr. Ritchie:

This responds to your December 21, 2010 email requesting clarification on the materials of trade (MOT) exception defined in § 171.8 and specified in § 173.6 of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Your questions are restated and answered as follows:

Q1.) May a carrier transport 200 kg of MOT on each vehicle of a truck and trailer combination, or is the transport as a MOT restricted to 200 kg for the combination?

A1.) The aggregate gross weight of 440 pounds (200 kg) as described in § 173.6(d) is that of the MOT located on the entire motor vehicle, which as defined in § 171.8 is a vehicle, machine, tractor, trailer, or semitrailer, or any combination thereof, propelled or drawn by mechanical power and used upon the highways in the transportation of passengers or property. As such, the gross weight of all MOT in the tractor and trailer(s) attached to a tractor may not exceed 440 pounds (200 kg).

Q2.) May a vehicle transport both MOT and other fully regulated hazardous materials?

A2.) The answer to your question is yes. As indicated in §173.6(e) a MOT may be transported on a motor vehicle with other hazardous materials without affecting its eligibility for exceptions provided by §173.6. The fully regulated hazardous materials must comply with all applicable HMR requirements.

Q3.) If a vehicle transports 200 kg of MOT, and other non-bulk Table 2 hazardous materials exceeding the 200 kg limit or otherwise ineligible for the MOT exception, when is placarding of the vehicle required?

A3.) A vehicle containing a maximum aggregate gross weight of 440 pounds (200 kg) of MOT and non-bulk shipments of other hazardous materials listed in § 172.504 Table 1 or 2 may be placarded as if the MOT were not on the vehicle. For example, if 1,441 pounds of hazardous materials which, other than exceeding the 440-pound weight restriction, meet the requirements of the MOT exception are transported by motor vehicle, the first 440 pounds may be transported under the exception; the remaining 1001 pounds is subject to the HMR, as applicable, e.g., placarding, labeling, marking, etc.

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



Ben Supko

Acting Chief, Standards Development Branch

Standards and Rulemaking Division

171.8, 173.6, 172.504

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
173.6 Materials of trade exceptions