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Interpretation Response #99-0225 ([HAZMATEAM, INC.] [Mr. Leo Traverse])

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

Interpretation Response Details

Response Publish Date:

Company Name: HAZMATEAM, INC.

Individual Name: Mr. Leo Traverse

Location State: NH Country: US

View the Interpretation Document

Response text:

September 29, 1999


Mr. Leo Traverse                               Ref No. 99-0225
12 Kimball Hill Road
Hudson, NH 03051-39155

Dear Mr. Traverse:

This is in response to your letter dated August 20, 1999, concerning the meaning of the plus (+) sign in Column I of the Hazardous Materials Table (HMT) under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).  Specifically, you ask if the appearance of a plus (+) sign is an indication that the proper shipping name may not be changed, even if the material is in a mixture.

The plus (+) sign in Column 1 of the HMT fixes the proper shipping name and hazard class for certain materials without regard to whether the material meets the hazard class shown in column 3 of the HMT.  However, this applies only to materials which are essentially pure, or of a technical grade.  The plus (+) sign eliminates shipper discretion in determining whether a material meets the defining criteria for a hazard class.  The proper shipping name is no longer fixed if the hazardous material is mixed with another hazardous material or a substantial amount of a non-hazardous material.  The plus (+) sign is no longer considered when the mixture or solution no longer exhibits the same hazard to humans as the technical or essentially pure grade of the material.  In that case, the most appropriate description for the material shall be determined in accordance with § 172.101(c) (12).

I hope this information is helpful.  If you have further questions, please do not hesitate to contact this Office.



Delmer F. Billings
Chief, Standards Development
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
171.1 Applicability of Hazardous Materials Regulations (HMR) to persons and functions