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Title: Tankers in US waters

Journal Article · · Oceanus; (United States)
OSTI ID:5629195

About 200 US flag tankers operate between US ports; the import trade consists of 30-40 more US tankers and 600-700 foreign tankers. US ships have 50% as many spills per port call as Liberian tankers and 20-33% as many as foreign tankers as a whole. There is mounting evidence that ships are prone to have a rather constant number of spills per year irrespective of variations in port call exposure. When spill incidence is measured per ship time, the US tanker margin over foreign fleets is only 2-3 instead of 3-6. For 1973-1975, 76% of all US tanker spills were <100 gal, compared with 65% of all flag of convenience spills. The probability of no tanker losses in a one-year period in US waters is only 0.22. One-half the losses can be expected to occur in conditions favorable to a spill in coastal waters. In any given year, the US tanker fleet of 235 vessels >1000 gross registered tonnage can be expected to have about 100 spills in US waters, while foreign flag ships contribute another 250 spills. The largest US tanker spill in a one-year period is <5000 gal; the median value for the largest spill from foreign tankers is closer to 50,000-100,000 gal.

OSTI ID:
5629195
Journal Information:
Oceanus; (United States), Vol. 20:4
Country of Publication:
United States
Language:
English