The open, competitive shipping policies of the six countries making up the Association of Southeast Asian Nations represent one of the global maritime industry's recent success stories, a new report says.

While those open policies could change, the U.S. government's past success in dealing with unfavorable shipping conditions suggests that it could probably prevent their implementation, according to SRI International, a San Francisco-based research group.The Asean countries - Brunei, Singapore, Indonesia, Malaysia, Philippines, and Thailand - re-evaluated their shipping policies in the mid-1980s. Because of pressure from exporters and domestic industries, most of those governments recognized that restrictive shipping policies frequently result in the use of higher-cost, lower-quality carriers, reducing their competitiveness in world markets, the report says.

Accordingly, their ocean carrier policies were liberalized to the extent that they refrained from adopting the Code of Conduct for Liner Conferences, developed by the United Nations Conference on Trade and Development as a means of promoting the merchant fleets of Third World countries.

The code, implemented in October 1983, called for a cargo-sharing scheme whereby the fleets of importing and exporting nations would each handle 40 percent of their liner trade, with the remaining 20 percent open to fleets of other countries.

The SRI report also praised the Asean members for improving their ports, making port clearances and documentation easier, and cutting subsidies to their own merchant fleets, SRI reported.

Asean is important to U.S.-flag liner companies because the region accounts for 34 percent of the trans-Pacific cargo they handle, the report finds.

The economies there, broadly speaking, are export-oriented. And while heavy in commodities, they are diversifying into manufacturing, the report adds.

Despite the upbeat picture the study paints, it notes that of continuing concern . . . is the fact that shipping policies in the Southeast Asia region have been changed in the past, and could quickly become more restrictive, especially those involving access by cross traders.

That was reference to non-U.S. or third-flag carriers operating between those nations.

Carriers in the U.S.-Asean trades would continue to experience good growth compared with other, more established trades if economic growth and minimal shipping barriers continue to exist in that area, SRI adds.