Pacific Maritime Association

I N D U S T RY A S S E S S M E N T S Logs are converted to board feet using the Brereton Log Scale. The Brereton Log Scale is used to calculate the volume of a log directly into board feet by approximating its shape as a truncated cone. Although today the Scribner Log Scale is the most commonly used method for scaling logs, the Brereton scaling method remains the basis for log conversion to board feet. There is no uniform standard formula for accurately making a conversion. However, it has been the practice to "convert" from the Scribner Log Scale by multiplying the Scribner board feet by 1.7 to obtain Brereton board feet before converting to revenue tonnage. Automobiles (including light trucks), regardless of how manifested, are reported based on the cubic measurement of the vehicle. Nearly all automobile shipments are correctly manifested with cubic measurements. In instances where cubic measurement is not available, marine and cargo surveyors compile listings of cubes and weights for each automobile model and type by year. Bulk Cargo is reported on the basis of weight. Bulk Cargo is any commodity that by the nature of its unsegregated mass is loaded or unloaded and carried without wrapper or container and received and delivered by carriers without transportation mark or count. Bulk cargoes are usually handled by pouring, by pumping or by mechanical conveyers. Bulk cargo also includes any liquid cargo for which members of the bargaining unit were paid for activity in its loading or discharging. West Coast Tonnage Statistics The revenue tonnage data submitted to PMA by tonnage reporting companies are subject to audit by an independent auditing firm. Such periodic reviews as well as updated information from reporting companies sometimes require changes to previously published tonnage data. Current West Coast revenue tonnage data is always available online at www.pmanet.org. It is important to note that PMA data include all "dry" cargo handled in ports in California, Oregon and Washington. The official U.S. Waterborne Transportation Statistics published by the U.S. Maritime Administration show foreign trade by type of carrier (liner, tanker and tramp), and do not include domestic tonnage moved to and from Alaska and Hawaii, nor do they contain PMA tonnage described as coastwise and U.S. intercoastal tonnage. PMA data do not include tanker liquid bulk or LPG carrier cargo. The U.S. Army Corps of Engineers publishes domestic cargo tonnage data. Government agencies report tonnage based upon reported actual weight and not in terms of revenue tonnage used by PMA. The official U.S. Waterborne Transportation Statistics show import and export cargo data summarized by port by customs district, whereas PMA data are summarized by port, port area and PMA administrative area. The Maritime Administration data provide detail regarding the cargo type, cargo origin, carrier type, value and the country of import or export, in addition to other information. Changes in Reporting Categories Revenue tonnage reporting categories have changed over the years. For example, automobiles were reported as General Cargo until 1962 after which they were reported separately. Automobiles in containers were reported in the Container category through 1983; beginning in 1983, autos and trucks containerized for the convenience of the carrier could be reported in the Automobile category at the option of the carrier. Cargo in containers was reported as General Cargo until 1969, after which containerized cargo tonnage is reported separately. Beginning in 1984, cargo in containers is reported as TEUs (twenty-foot equivalent units) and converted into tonnage at the rate of 17 revenue tons for each TEU. A TEU is defined as 20 linear feet of outside container length and is equivalent to a Revenue Unit (RU) described in the PMA Tonnage Reporting Manual distributed to reporting companies. Coastwise Tonnage Coastwise revenue tonnage represents a subset of the total revenue tonnage reported to PMA. Reporting separate coastwise tonnage for each of the commodity categories was instituted in November 1989. Previously, there were provisions for only General Cargo and Lumber & Logs to be reported as coastwise tonnage. Other coastwise commodities had to be reported in the Offshore and Intercoastal category. Coastwise cargo is assessed only on discharge, however, coastwise loaded cargo is reported for statistical and auditing purposes. Cargoes inbound from British Columbia represent another subset of total revenue tonnage, when such cargoes are present. Cargo operations at SSA Terminals at the Port of Seattle. 53 p a c i f i c M a r i t i M e a s s o c i a t i o n

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