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Interpretation Response #05-0203 ([U.S. Coast Guard] [Mr. P.A. Cooley, MSTC])

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

Interpretation Response Details

Response Publish Date:

Company Name: U.S. Coast Guard

Individual Name: Mr. P.A. Cooley, MSTC

Location State: VA Country: US

View the Interpretation Document

Response text:

Oct 28, 2005


Mr. P.A. Cooley, MSTC                      Reference No. 05-0203
U.S. Coast Guard
End of State RT 238
Yorktown, VA 23690-5000

Dear Mr. Cooley:

This responds to your August 26, 2005 memorandum requesting clarification on the definition of “fore and aft” and “athwarthips” regarding section § 176.83(0(4) of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you request the definition of these terms in the context of general container segregation under
§ 176.83(0(4).

“Fore and aft” and “athwartships” are common nautical terms. In the context of 49 CFR 176.83(0(4), “fore and aft” means a container space of not less than 6 m (20 feet) long or “athwartships” means a container space of not less than 2.5 m (8 feet) wide when the, container is in parallel (bow to stern) with the keel.

In the context of the diagram (“separated from”.2 from chapter 7.2 of the International Maritime Dangerous Goods (IMDG) Code) that accompanied your memo, “fore and aft” means one container space in the direction parallel with the keel (bow to stern) and “athwartships” means one container space perpendicular to the keel (port to starboard) when the container is aligned in parallel to the keel. Two closed incompatible containers are permitted to be segregated by one bay and two rows, as described in your memo, because the containers are one container space, 2.5 m (8 feet) apart in the athwartships (port to starboard) direction.

I hope this answers your inquiry.



John A. Gale
Chief, Standards Development
Office of Hazardous Materials

171.8, 176.83(f) (4)

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
176.83 Segregation