Coast Guard Improves Inspection Program To Detect Unsafe Tankers

More Oil Is Shipped In U.S. Waters Than Any Other Commodity; Petroleum And Petroleum Products Account For 40 Percent Of The Cargo Shipped Through U.S. Waters C o a s t Guard inspections have not always been reliable in detecting unsafe tankers. For tankers registered in the United States, such problems as too few inspectors, inexperienced inspectors, and limited inspection procedures have hampered the Coast Guard's inspection efforts.

Tankers are an important means of transporting petroleum and petroleum products and they are also a significant source of oil pollution.

The prevention of accidents or mishaps that can cause oil spills is a principal reason that the Coast Guard periodically inspects the condition of tankers. According to Coast Guard officials, a number of factors can contribute to unsafe vessel conditions including the following: • I n c r e a s e d age: The world tanker fleet has aged dramatically.

Generally, according to Coast Guard officials, the older a tanker is, the more likely it is to develop signifi- cant problems, such as deterioration of structural supports or breakdowns of key machinery or equipment.

While age alone was not typically viewed by participants at the 1991 International Marine Safety Workshop as an important factor in vessels' not meeting international standards, it can play a crucial role when coupled with poor maintenance.

• Lower maintenance levels: Problems that can develop from vessel aging can often be prevented by good maintenance, according to Coast Guard officials. However, these officials stated that maintenance has decreased in recent years, in part because of depressed financial conditions in the shipping industry.

Maintaining tankers can be expensive. For example, an oil industry representative told us that shipyard maintenance on large oil tankers over 10 years old typically costs between $3 million and $6 million during the 2-year drydocking cycle.

• Use of high-tensile steel: Coast Guard officials state, as a cost-saving measure, vessels over the last 20 years often were built with hightensile steel. This steel, also called high-strength steel, saves money because less of it is needed in construction, and the vessel's resulting lighter weight allows more cargo to be carried. However, a 1990 Coast Guard study on structural failures found that vessels built with hightensile steel are more likely to develop cracks in their hulls or supporting beams.

• Bad weather: According to Coast Guard officials, severe weather conditions, such as those encountered by TAPS vessels in the Gulf of Alaska, can put stress on the hull and supporting structures and cause cracks to develop.

More oil is shipped in U.S. waters than any other commodity. According to the U.S. Army Corps of Engineers' Waterborne Commerce of the United States, petroleum and petroleum products accounted for more than 40 percent of the cargo shipped to, from, or through the United States by water in 1988, more than twice as much as the next most common cargo. As figure 1.1 shows, the amount of oil shipped by water in 1988 is roughly the same as was shipped in 1976—nearly 860 million tons.

Tanker Casualty and Pollution Rates Figure 1.2 shows the number of U.S. tanker casualties reported between 1980 and 1988. In addition, a 1990 study by the National Research Council on crew size and maritime safety found that rates of maritime accidents and personnel injuries, worldwide and in the U.S. fleet, have declined steadily over the last 20 years. For example, data show that accident rates for large tankers (those over 6,000 gross tons) have declined to about 2 per 100 vessels, a level roughly 20 percent below those of the mid- to late 1970s.

In addition to reports of ship casualties, the Coast Guard receives reports of pollution in U.S. waters.

Although the number of reported spills from tankers has declined since the mid-1970s, the amount of oil spilled each year varies greatly.

In the first 9 months of 1990, the Coast Guard was notified of 303 pollution incidents in which tankers released about 1.8 million gallons of oil and hazardous substances, nearly 24 percent of the oil and hazardous substances discharged into U.S. waters and reported to the Coast Guard that year.

Age of Tanker Fleet The proportion of older tankers in the world fleet is growing. From 1981 to 1990, the percentage of the world fleet (measured in tonnage) that was at least 15 years old has increased from about 15 percent to nearly 45 percent. The same trend is evident when the number of aging tankers is expressed as a percentage of the number of tankers. The percentage of the world tanker fleet that is 15 or more years old has increased significantly since 1970, when about 30 percent of the world's tankers were 15 years old or older.

By 1990, the percentage of tankers at least 15 years old had increased to nearly 50 percent.

Compared with the world tanker fleet, the U.S. tanker fleet includes a greater percentage of tankers that are more than 15 years old. According to the Coast Guard, in 1990, more than 62 percent of U.S. tankers were at least 16 years old, while nearly one-third (32 percent) were 30 or more years old. Figure 1.3 shows the ages of U.S. tankers in 1990. Meanwhile, about 48 percent of the world tanker fleet was at least 15 years old in 1990, and only about 8 percent was at least 30 years old.

Figure 1.4 shows the age of the world tanker fleet in 1990.

Since the 1950s, the percentage of the world's tanker fleet operating under the U.S. flag has declined significantly. In 1955, more than 14 percent of the world's tankers were registered in the U.S. By 1990, about 4 percent of the world's tankers were registered in the U.S. In addition, many of the tankers serving the United States are registered in other countries. In 1990, for example, foreign tankers visited U.S. ports nearly twice as often as U.S. tankers.

The Coast Guard has taken and plans to take many actions to strengthen its tanker inspection procedures. For example, it began requiring operators of U.S. TAPS tankers in 1990 and of foreign TAPS tankers in 1991 to prepare inspection plans for areas on their tankers susceptible to cracking. The plans are to lay out a strategy for monitoring these areas and tracking the effectiveness of repairs.

Changes to increase the flexibility of inspections are also under consideration in an initiative called the Merchant Vessel Incentive Inspection Program.

Maritime Reporter Magazine, page 53,  Mar 1992

Read Coast Guard Improves Inspection Program To Detect Unsafe Tankers in Pdf, Flash or Html5 edition of March 1992 Maritime Reporter

Other stories from March 1992 issue


Maritime Reporter

First published in 1881 Maritime Reporter is the world's largest audited circulation publication serving the global maritime industry.