Page 64: of Maritime Reporter Magazine (November 2003)

the marine industry. It is particularly critical for those building or repairing

U.S. Coast Guard certificated commer- cial vessels in the un-classed domestic market where the Coast Guard does not explicitly regulate either the grade or temper of aluminum, and independent oversight by classification societies rarely is requested. In creating the new specification, it was noted that: • the production of high magnesium aluminum is sensitive to process changes that can have an impact on the corrosion resistance of the particular temper of the aluminum alloy being pro- duced: • not all major classification societies allow the use of 5083 H321. Others that do, had further requirements, such as ensuring the material was coated, when used in salt water applications; • the current and widely used indus- try practice of specifying aluminum in accordance with ASTM B209 may be insufficient. Further, the commonly accepted H116 temper with ASTM G66 testing only, may not be absolute in guarding against intergranular corro- sion, despite its apparent problem free service record over the last 30 or so years.

The Coast Guard intends to review its regulatory scheme and current policy directives to determine the applicability of this new specification. Specifically, comments and information on the domestic industry's experience with alu- minum in the marine environment out- side the Pacific Northwest, in areas of high activity such as the Gulf Coast, will be solicited to assist the Coast Guard in the evaluation and appropriate applica- tion of this specification.

Please contact Marc Cruder mcrud- [email protected] of the Coast Guard's

Quality Assurance and Traveling

Inspection Staff at Coast Guard

Headquarters if you have questions or comments about the regulatory impact of this specification or you would be interested in participating in a working

Marine Materials group to reviewise the Coast Guard's current policy guidance regarding alu- minum and its use in the construction of inspected small passenger vessels.

Note - The new specification will be available from ASTM International by mid-October at: http://www.astm.org/.

Ships have become terrorist targets and potential terrorist weapons, ag

November 2003

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