THE PROBLEM of gas-freeing tank vessels after discharging combustible or flammable cargoes is one which has concerned the maritime industry and the Coast Guard for some time. In order to assure safe practices and procedures for such vessels, every possible source of information regarding gas freeing and inerting should be developed.

In 1962 the Commandant of the Coast Guard recommended to the Secretary of the Treasury that a special committee, composed of representatives from federal agencies, industry, and others concerned with maritime safety, be created to look into all aspects of the problem.

The Secretary of the Treasury concurred with this recommendation and the Committee was established, consisting of:

October 1963

CHAIRMAN:

Herbert L. Seward, Emeritus Professor of Mechanical and Marine Engineering, Yale University, and former Professor of Maritime Economics at the U.S. Coast Guard Academy.

MEMBERS:

Dr. Homer Carhart, Head, Fuels Branch, Naval Research Laboratory, Department of Navy.

E. Carroll Creitz, Fire Research Section, National Bureau of Standards, Department of Commerce.

Dr. Glenn H. Damon, Staff Research Coordinator, Bureau of Mines, Department of the Interior.

Arthur R. Gatewood, President, American Bureau of Shipping.

Ludwig C. Hoffmann, Chief, Office of Ship Construction, Maritime Administration, Department of Commerce.

Charles S. Morgan, Assistant General Manager, National Fire Protection Association.

Richard Parkhurst, Former Chairman, Boston Port Authority and former Commissioner, U.S. Maritime Commission (Ret.).

Captain Wm. S. Vaughn, USCG, Chief, Testing and Development Division, Office of Engineering, Coast Guard Headquarters. SECRETARY:

Lieutenant Clyde T. Lusk, Jr., USCG, Merchant Marine Council Staff, Coast Guard Headquarters.

The Committee completed its work and submitted its final report in August 1963. The work was divided into three phases: (1) Gathering of data and information, (2) Preparation of findings, and (3) Preparation of recommendations.

167

FOREWORD

As a foreword to its findings and recommendations, the Committee stated that "The transportation of flammable liquids in large oceangoing tankers has been increasing for many years. While the bulk transport of such liquids is relatively cheap and provides a ready means of distributing the world's supplies of such materials, there are certain inherent hazards in the operations which have caused considerable concern. The handling of such hazardous materials by land transportation results in numerous accidents and it is not surprising that sea transportation of such materials has also resulted in accidents. The principles involved in the initiation and propagation of fires and explosions are identical regardless of the locale of the operation.

"Safety" is a term which is more talked about and less understood than many other industrial problems. There is no operation which can be described as absolutely safe. Safety can be described only in relative terms, and is based on experience in situations similar to those under consideration.

The hazards connected with any industrial operation are often difficult to ascertain with any degree of certainty. In fact, there are many areas of operation where the degree of hazard cannot be assessed. Reasons for this difficulty are severalfold, but a most important factor is that most operations depend upon human judgment. Even highly mechanized operations require a certain dependence on human effort and judgment. Since this judgment varies so markedly from individual to individual and with the physical condition of any given individual the variation in hazard may be very wide. Additionally, there is a degree to which all human beings exhibit a certain amount of carelessness even though they will normally deny such behavior. The actual technical hazards involved in a given operation are generally statistical in nature and it is possible to estimate the probability of an accident happening. However, when technical problems are superimposed upon the human problems it is often next to impossible to arrive at a final conclusion which has any reasonable degree of accuracy.

In view of the uncertainty regarding the actual hazards involved in any operation or series of operations, one may readily ask whether it is possible to set up any given safety standards. Safety standards can and should be set up but they should be based on the most hazardous operation known to exist in any given situation. If economically feasible, the safety en

gineer will then add a factor of safety to cover the unforeseen circumstances which cannot be measured quantitatively. On this basis we believe it reasonable to formulate safety standards. This does not mean that an accident cannot happen.

It must be recognized that there is always danger associated with the handling and transport of flammable materials. There is, of course, not the slightest question that a tanker is in safer condition when gas free on a ballast voyage than when not gas free. A practical difficulty is that gas freeing a tanker is always a hazardous operation.

Of prime consideration in the Committee's deliberations are the hazards presented aboard a tanker, under varying circumstances, by empty, nongas-freed cargo tanks. These are likely to be found under each of the following three conditions: while the vessel is under way, is transferring cargo, or is undergoing repairs.

In its approach to the solution of the problem assigned, the Committee has been mindful of the far-reaching implications of its findings and recommendations both on the national and international scene. It must be understood that the circumstances from which these problems arise are neither unique in character nor peculiar to the United States.

We are concerned here with the transportation by water of a variety of liquid products which are inherently hazardous. But these same products are not transported solely by water. They move also in interstate commerce over our highways, our railroads and to a lesser degree by air. Thus any limitations or controls established in the name of safety for the waterborne movement of these products must be consistent with corresponding controls established for the same reason in reference to other common forms of transportation where hazards to public safety are by no means less severe.

We are conscious also that, unlike our land transportation operations, seaborne commerce is international in character. The fact that there is a domestic coastwise segment of these operations does not alter the basically international character of the whole, because our domestic waterways, harbors, and terminal facilities are used by vessels of all maritime nations. By the same token, vessels of the United States merchant fleet must use the port facilities of foreign lands.

Elaborate means have been developed over a period of many years for the negotiation and agreement among maritime nations on matters of safety. It would be unwise for this Committee to propose controls on

tankship operations which might easily upset the balance of our relations with other maritime nations and handicap our own tankship operators unless such proposed controls provided safeguards deemed to be essential to public safety.

In our consideration of these points, we have consulted with knowledgeable representatives of foreign tanker fleets to inform ourselves of accepted safety practices in these quarters. We are convinced that the established practices of the United States tankship operators, as well as the regulations of the Coast Guard with which they must comply, are in the van among their counterparts overseas.

The Committee feels that one of the major steps taken with regard to the advancement of maritime safety was the enactment of the Tank Vessel Act of 1936. Under this law the United States Coast Guard is given the responsibility for inspecting tank vessels and for promulgating rules and regulations for the bulk movement of flammable and combustible liquids by water.

In the United States-flag ocean-going tanker fleet, there are about 400 vessels of 1,000 gross tons and over. These include some 80 in present inactive status, mostly in the National Defense Reserve fleet and do not include small tankers operating exclusively on the Great Lakes and Inland Waterways. Numerically, these 400 vessels comprise about 10 percent of the world tanker fleet and while there are many new ships in the lot, their average age of 13.80 years is the highest among tanker fleets of all flags. United States owned or controlled companies also hold interests in foreign flag tankers. These include about 265 so-called "Flags of Necessity" or "Flags of Convenience" vessels, considered by the Department of Defense to be under effective United States control for use in the event of war or national emergency. These latter tankers are, for the most part, modern, large, high-speed vessels, with an average age well below that of United States-flag tankers.

Size, speed and cargo tank volume of tankers have all increased as compared to the standard T-2 WWII type ** *. These changes in the modern tanker, and the increasingly varied composition of cargoes in tankers and barges (already, by Coast Guard estimate, more than 140 different liquids are carried or proposed to be carried) compound the need for greatest alertness safetywise. This statement applies to construction, ship and cargo handling, aids to navigation especially in congested waters, crew training and enforcement of regulations."