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Interpretation Response #99-0319 ([Department of the Army] [Mr. David B. Terry])

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

Interpretation Response Details

Response Publish Date:

Company Name: Department of the Army

Individual Name: Mr. David B. Terry

Location State: VA Country: US

View the Interpretation Document

Response text:

February 4, 2000


Mr. David B. Terry                                Ref. No. 99-0319
Assistant Deputy Chief of Staff                             99-0303
   for Operations
Department of the Army
Headquarters, Military Traffic Management Command
5611 Columbia Pike
Falls Church, VA 22041-5050

Dear Mr. Terry,

This is in response to your letter requesting clarification of the requirements in The Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) regarding certain explosive definitions and the required placarding for Class 1 materials when compatibility groups G, C, D and E are transported together by aircraft or vessel.  Your questions are paraphrased-and answered below.

Ql.       What is the meaning of the term “fireworks” as used in §§ 174.8(g) (3) (vi) and 177.848(g) (3) (vi)?

Al.        The term "fireworks" refers to Class 1 (explosive) materials
that have been assigned the proper shipping name "Fireworks" from the Hazardous Materials Table.  Also, the definition of the term "fireworks" is defined in § 173.59 as 'pyrotechnic articles designed for entertainment."

Q2.    What is the meaning of the terminology "special stowage' in § 177.848(g)(3)(vi)?

A2.    The term “special stowage”  is a term used for the stowage of hazardous materials aboard vessels.  The term was inadvertently taken from the vessel language of the 49 CFR and does not refer to any stowage requirements in rail or highway transportation.  This will be corrected in an upcoming rulemaking.

Q3.    What is the meaning of the terminology "explosive article" and ,explosive substance" and where in the HMR are they defined?

A3.    The terms "explosive article" and “explosive substance” are not defined in the HMR.  It is the opinion of this Office that the term "explosive article" refers to an article that contains one or more explosive substances.  The term "explosive substance' refers to a solid or liquid substance (or a mixture of substances) which is in itself capable by chemical reaction of producing gas at such temperatures and pressure and at such speed as to cause damage to the surroundings.  Although there are no specific definitions in the HMR for 'explosive  article' or 'explosive substance,' numerous examples of each are described in 49 CFR 173.59. For example, bombs, detonators and flares are explosive articles and smokeless powder and solid propellant are explosive substances.

Q4.    When shipping by aircraft or vessel, what are the placarding requirements when transporting explosive articles of compatibility group G with articles of compatibility groups C, D and E?

A4.    As prescribed in § 172.504(g), Class 1 materials transported by aircraft or vessel must be placarded with the appropriate Class 1 placards (see § 172.522) Each placard must display the applicable compatibility group.

Q5.    Section 172.522(b) states that the symbol “*” shall be replaced with the appropriate compatibility group letter.  Does this mean that multiple letters, such as compatibility groups G, C, D and E may be placed on one placard when shipped together?

A5.    No. Presently, the HMR requires compatibility groups G, C, D and E to be placed on separate placards. (Also, see A7.)

Q6.    Section 172. 504 (f) (1) states, 'When more than one division placard is required for Class 1 materials on a transport vehicle, rail car, freight container or unit load device, only the placard representing the lowest division number must be displayed.' Does this apply when more than one compatibility group placard is  required for Class I materials?

A6.    No. Section 172.504 does not address compatibility groups. (Also, see A7.)

Q7.      If the answer is no, will you allow this letter to serve as a 'petition' to use one placard versus several placards when compatibility group G is shipped together with compatibility groups C, D, and E?

A7.      It is not clear what you mean by "petition." A petition for rulemaking (a request to change a requirement in the 49 CFR) must be filed in accordance with § 106.31. An exemption (a request for an exemption from a requirement in the 49 CFR) must be filed in accordance with § 107.105. Your letter does not provide the required information and, therefore, may not be used to serve as either a petition for rulemaking or an exemption.  However, we recognize the inconsistency in the compatibility group placarding requirements and are planning to propose this change in an upcoming rulemaking.

I hope this information is helpful.  Please contact us if you need additional assistance.


Hattie L. Mitchell, Chief
Regulatory Review and Reinvention
Office of Hazardous Materials Standards

174.81, 177.848

Regulation Sections

Section Subject
174.81 Segregation of hazardous materials
177.848 Segregation of hazardous materials