Groups representing 49 U.S. export industries today told the head of the U.S. Coast Guard they support an agency proposal they said would comply with an international maritime treaty requiring the total weight of a loaded ocean container to be certified in writing before the box is loaded aboard a vessel.

In a letter to Adm. Paul F. Zukunft, the Coast Guard's commandant, the groups, which represent the heart of U.S. export commerce, said the agency's approach, which would require shippers to certify the gross weight of the cargo and the ocean carriers the weight of the equipment, is a sensible approach to ensuring safe operations aboard ships and at marine terminals while allowing cargo to move in and through marine terminals without delay or disruption.

An amendment to the 102-year-old Safety of Lives at Sea (SOLAS) treaty requires shippers to certify the "verified gross mass" of a container before it is laden. The amendment, scheduled to take effect July 1, holds the force of law over the 171 member countries within the International Maritime Organization (IMO), the London-based organization that oversees the treaty. The amendment was adopted amid concerns that illegally overweight containers could contribute to a seagoing incident where a vessel could be sunk or damaged.

U.S. exporters maintain that it is unrealistic to ask them to verify tare weights of empty container because they don't own or control the boxes. The shippers said their role should be to accurately certify the gross weight of the cargoes, a responsibility they have today. Steamship lines and U.S. ports have said publicly that shippers bear the sole responsibility for certifying the weight of a loaded container. According to the exporters' letter, however, several carrier executives have said the Coast Guard's proposal is practical. The letter did not identify the executives.

Late last month, Rear Adm. Paul Thomas, assistant commandant of prevention policy for the Coast Guard, which enforces the safety of U.S. seafaring, advised that the intent of the amendment could be satisfied if shippers submit the gross weight of the cargo and carriers attach a separate document certifying the weight of the empty box. He urged shippers and carriers to resolve the issue as a "business practice," adding the Coast Guard has no power to apply SOLAS to U.S. shippers.

The exporter coalition had called on the U.S. government to delay the amendment's implementation until the country's top 15 trading partners adopted it. However, Thomas, in a blog post last month, said a U.S. delay of the rule's implementation would prevent other nations from loading U.S. cargoes aboard their vessels at U.S. ports, thus putting U.S. exporters at a disadvantage.

In today's letter, the groups said they would be willing to provide to carriers annual written confirmation in service contracts or other formal documents that the cargo weights are accurate.