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~ on ~~ As mmil1ee on Assessing Passenger Submersible Sang Marine Board Common on Engineering and Technical Systems National Research Crunch LION ~ PRESS ~ashinglon, D.C. 1~
NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the panel responsible for the report were chosen for their special competencies and with regard for appropriate balance. This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Frank Press is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Robert M. White is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Samuel O. Their is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Frank Press and Dr. Robert M. White are chairman and vice-chairman, respectively, of the National Research Council. The program described in this report is supported by Cooperative Agreement No. 14-35-0001- 30475 between the Minerals Management Service of the U.S. Department of Interior and the National Academy of Sciences. Limited copies are available from: Marine Board Commission on Engineering and Technical Systems National Research Council 2101 Constitution Avenue, N.W. Washington, DC 20418 Library of Congress Catalog Card Number 90~3195 International Standard Book Number 0-309-04232-1 Copyright °1990 by the National Academy of Sciences. S115 Printed in the United States of America Additional copies are for sale from: National Academy Press 2101 Constitution Avenue, N.W. Washington, DC 20418 (202) 334-3313 1-800-624-6242
COMMI17EE ON ASSESSING PASSENGER SUBMERSIBLE SAFE:1Y WILLIAM M. NICHOLSON, Chairman, U.S. Navy (retired), Annapolis, Maryland DONALD L. CALDERA, Park Ridge, New Jersey HARRY ~ JACKSON, Groton, Connecticut COLIN M. JONES, Colin M. Jones Consulting Engineers, Honolulu, Hawaii JOYCE ~ MCDEVIIT, ARC Professional Services Group, Springfield, Virginia JOHN BRADFORD MOONEY, JR. (NAE), Harbor Branch Oceanographic Institution, Fort Pierce, Florida HAROLD E. PRICE, Essex Corporation, Alexandria, Virginia JOHN ~ RENZO, Lockheed Advanced Marine Systems, San Diego, California LAWRENCE ~ SHUMAKER, General Offshore Company, St. Croix, U.S. Virgin Islands BARRIE B. WALDEN, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts DON WALSH, International Maritime, Inc., San Pedro, California Staff DONALD W. PERKINS, Staff Officer COURTLAND LEWIS, Editor DELPHINE D. GLAZE, Project Assistant · ·
MARINE BOARD BRIAN J. WATT, Chairman, lithe Ralph M. Parsons Company Ltd. ROBERT N. STEINER, Mce-Chairman, Delaware River Port Authority ROBERT G. BEA, NAE, University of California at Berkeley JAMES M. BROADUS III, Woods Hole Oceanographic Institution SYLVIA ALICE EARLE, Deep Ocean Engineering LARRY L. GENTRY, Lockheed Advanced Marine Systems ROBERT T. HUDSPETH, Oregon State University MARCUS J. JOHNSON, Sea-Land Service, Inc. JUDITH T. KILDOW, Tufts University BERNARD LE MEHAUTE, University of Miami WILLIAM R. MURDEN, NAE, Murden Marine, Ltd. JOSEPH D. PORRICELLI, ECO, Inc. PAUL ~ SANDIFER, South Carolina Wildlife Marine Resources Department JERRY R. SCHUBEL, State University of New York at Stony Brook PETER R. TATRO, Scientific Applications International Corporation GEORGE P. VANCE, Mobil Research and Development Corporation DON WALSH, International Maritime, Inc. EDWARD WENK, JR., NAE, University of Washington, Emeritus Staff CHARLES ~ BOOKMAN, Director DONALD W. PERKINS, Associate Director SUSAN GARBINI, Project Officer ALEXANDER B. STAVOVY, Project Officer WAYNE YOUNG, Project Officer DORIS C. HOLMES, Staff Associate AURORE BLECK, Senior Project Assistant DELPHINE D. GLAZE, Administrative Secretary GLORIA B. GREEN, Project Assistant CARLA D. MOORE, Project Assistant V
PREFACE The U.S. Coast Guard is required to regulate commercial marine operations in the interest of public safety. Development of an expanding commercial passenger-carry~ng submarine Tourist submersibles) industry has led recently to the development of new regulations for this special class of vessel and to a need for new inspection and certification requirements in Coast Guard field offices. At present there are seven tourist submersibles operating under the jurisdiction of the Coast Guard. The Coast Guard recognizes that its experience in this area is limited, and that the industry presents novel features, both technologically and operationally. Therefore, the Coast Guard asked the Marine Board to review and assess the hazards involved in tourist submersible development and operations, and to advise them of the approaches that might best be used to ensure public safety. A committee was formed to include experts in all of the technical aspects of naval architecture for submersibles and deep submergence, technologies which have developed primarily over the last 30 years for research, military, or industrial purposes, but which have seen very few public commercial applications. The committee also included experts in systems safety, human factors, as well as an expert in management of cruise ship businesses. Members of this committee visited two current operations in U.S. waters, visited the assembly plant of a currently active builder-operator, and viewed presentations by experts in fire prevention, acrylic material properties, and life support systems. All members of the committee made one or more dives in a tourist submersible. Special briefings and discussions with the American Bureau of Shipping and the Coast Guard were also undertaken. Three meetings of the full committee were held. This report presents the committee's findings and its conclusions and recommendations. ACKNOWLEDGMENTS The committee appreciates the support of Commander Stephen L. Johnson, U.S. Coast Guard, who served as liaison representative. He was particularly helpful and responsible in providing the committee with data and documentation about passenger submersible certification. Mr. Brian Van Mook of the American Bureau of Shipping responded to the committee's requests for nonproprietary classification information. Mr. John Pritzlaff served as the liaison with the Society of Naval Architects and Marine Engineers (SNAME), which has provided much of the leadership in non-military submersibles standards development for over two decades. In addition, Mr. Pritzlaff's extensive library and photographs of submersibles worldwide comprised a rich resource to be tapped for this report. His suggestions and efforts are much appreciated. The committee also recognizes the cooperation of Sub-Aquatics, Incorporated, in the organization and support of the committee's visits to their operations at St. Thomas, U.S. Virgin Islands, Hawaii, and vessel construction at Tacoma, Washington. Mr. John Witney, Vice President of Engineering, Sub- v
Aquatics, Incorporated, and Mr. Jack McMahon, Manager of their St. Thomas operations, were particularly helpful, candid, and responsive to the committee's inquiries. Dr. Edward M. Briggs, of Southwest Research Institute, provided technical background concerning the use of acrylics in pressure vessels for human occupancy. Dr. Graham Hawkes, Deep Ocean Engineering, Incorporated, provided insight concerning stiffened cylinder theory and buckling. v'
CONTENTS EXECUTIVE SUMMARY CHAPTER 1: CHAPTER 2: INTRODUCTION AND OUTLOOK Nature and Status of the Tourist Submersibles Industry, 2 Precursors of Today's Tourist Submersible, 2 Recent Development of the Industry, 2 Present Tourist Submersible Programs, 7 Projected Trends in Tourist Submersible Development, 9 Business Considerations, 10 Market Development Potential, 10 Investment Aspects, 11 Governmental Responsibilities, 12 Summary, 12 EXISTING PROCEDURES FOR CLASSIFICATION AND CERTIFICATION OF TOURIST SUBMERSIBLES Rules and Regulations, 15 Design, 15 Plan Review, 15 Applicability, 16 Findings and Conclusions Regarding Classification and Certification, 17 ·e v'' . . 14
CHAPTER 3: TECHNICAL ASPECTS Ol? SYSTEM DESIGN Design and Construction, 19 Materials, 20 Structure, 22 Pressure Cycling, 23 Redundant and Backup Systems, 23 Stability, 24 Quality Control, 24 Conclusions and Recommendations Regarding Design and Construction, 24 Life Support Systems, 25 Air Supply/Regeneration, 25 Fire Suppression, 26 Emergency Breathing Apparatus, 26 Personal Flotation, 27 Conclusions and Recommendations Regarding Life Support, 27 Inspection, 28 Construction Inspection, 28 Periodic Inspections, 28 Conclusions and Recommendations Regarding Inspection, 30 CHAPTER 4: SYSTEM SAPPED ISSUES . . . System Safety Hazard Analysis, 31 Safety Review, 33 Recommendations Regarding System Safety, 34 ... 19 .. 31 CHAPTER 5: OPERATIONAL AND ADMINISTRATIVE CONSIDERATIONS 35 Manning, Training, and Licensing, 35 Manning, 35 Training, 36 Licensing, 36 Recommendations Relating to Manning, Training, and Licensing, 37 Passenger Management, 38 Normal Operations, 38 Abnormal or Emergency Operations, 40 Special Considerations, 40 Operations Manual and Safety Plan, 41 Training in Passenger Management, 41 Recommendations Relating to Passenger Management, 42 · · ~ v'~z
Emergency Response Planning, 42 Importance of Contingency Planning and Preparation, 42 Nature of Contingency Plans, 43 Recommendations Relating to Emergency Response, 43 NOTES ....... APPENDIXES APPENDIX A: DRAFT OF U.S. COAST GUARD CIRCULAR ON PASSENGER SUBMERSIBLES ................ APPENDIX B.: SUGGESTED INSPECTION REQUIREMENTS APPENDIX C: OPERATIONAL SAFETY ................................ 45 ....... 47 94 · 97 APPENDIX D: COMMENTARY ON TRAINING 101 APPENDIX E: CONTINGENCY PLANNING AND PREPARATION APPENDIX F: OTHER RELEVANT CONTINGENCY PLANS GLOSSARY . BIOGRAPHIES OF COMMITTEE MEMBERS DC 104 108 140 143
EXECUTIVE SUMMARY "Tourist submersibles" are commercially operated passenger-carrying submarines; they are used to conduct underwater sightseeing excursions at oceanside resorts and other tourist centers. Some tourist submersibles are converted research or industrial work vessels of a type known as deep submergence vehicles (DSVs). These are typically small vessels carrying a pilot and 2-3 passengers (although 6-8- passenger conversions of these submersibles will be launched beginning in 1990), which were designed to dive to great depths. Other larger vessels are built-for-the-purpose submersibles usually carrying 25-49 passengers and are designed to operate in shallow water at depths no greater than 150 feet. As a large-scale recreational enterprise, this industry is less than a decade old. Seven tourist submersibles are currently in operation in U.S. waters or in locations where the Coast Guard is responsible for safety (the U.S. Virgin Islands, Hawaii, Guam, Rota Island [Mariana Islands], and Saipan); this is the largest number of submersibles under one jurisdiction. Internationally, 18 other submersibles are operating in waters as diverse as the Cayman Islands and Switzerland. More are expected in the near future. Of the handful of builders of built-for-the-purpose tourist submersibles, two have already left the business, along with at least two operators. Given the newness of the industry, investment capital can be difficult to obtain, and initial and operating costs are high. Ticket sales must remain close to seating capacity on a sustained basis if a venture is to succeed. Little time is available for maintenance. Nevertheless, the industry leaders have shown that a well-planned, well-run operation can succeed financially. The realized and potential financial return from successful operations makes this an attractive new business development area with moderate expansion expected. Such expansion will be limited by availability of diving areas that offer good views, easy access, and market conditions. The American Bureau of Shipping (ABS) is the predominant technical organization in the United States for classification of ships. Worldwide, there are at least 17 ship classification societies, although only 7 command the majority of classification activity, viz., ABS, Lloyd's Registry of Shipping (U.K.), Det norske Veritas (Norway), Germanisher Lloyd (Germany), Bureau Veritas (France), Soviet Registry (USSR), and Nippon Kaiji Kyoka (Japan). The ABS has been the classification agency for all U.S. tourist submersibles to date and in fact has classed all but one of the tourist submarines currently in operation. Det norske Veritas is a non-U.S. classification agent for two submersibles now under construction. The U.S. Coast Guard is responsible for certification that vessels operate in U.S. waters meet technical and safety standards. The Coast Guard relies extensively (but not exclusively) ore the ABS As of December 1989. X1
technical rules, particularly in regard to the design of structures, and on assurance that new vessels comply with these rules. Construction inspections and periodic inspections thereafter are conducted jointly where possible. The Coast Guard maintains direct surveillance and approval of all operating vessels at the local level through the Captain of the Port (COTP) and the Officer in Charge, Marine Inspection (OCMI) (often they are the same person). Their cognizance includes approval of both technical and diving aspects of the operation of tourist submersibles. However, these officers have a wide scope of responsibilities and are not necessarily technically expert with regard to these new and sophisticated vessels. Current Coast Guard criteria for approval of the submersibles and their operations are based on those for surface craft of comparable size. This imposes on the COTP and OCMI, as well as on the individual Coast Guard inspector, the need to exercise judgment in areas that may be safety-critical. There have been no serious accidents to date aboard these vessels, although there have been several "near-misses," which have been quickly and successfully responded to. Current operational and technical activities appear to be, for the most part, professional and conscientious with regard to safely. However, the entry into the market of operators who have little or no experience in the operation of these vessels, combined with the probability of availability of lower-priced, second-hand vessels, gives rise to a concern that current standards might not be upheld in the future. Also, new submersible designs are being developed, while at the same time the innovative use of materials such as acrylics in hulls is being explored. Given these impending changes, the primary concern of the committee is that the Coast Guard develop a set of regulations or standards, procedures, and tests that will ensure that future submersible builders and operators meet and maintain the same or better standards found in operations observed to date. Given this concern, the committee chose to include in its scope of assessment an examination of all aspects of the systems, including design of the submersible, support systems, operating and maintenance considerations, crew qualifications and passenger management. It is evident that both the Coast Guard and ABS are headed in the right direction with revisions of rules and the Coast Guard's proposed circular for interpretation of existing regulations (see Appendix A). Continued close cooperation between the Coast Guard and ABS is essential. Additionally, rules developed for the U.S. industry and submersibles under U.S. cognizance may be relevant and useful to foreign tourist submersible operations. Specific areas of concern, discussed in detail in the report, and the committee's recommendations regarding those concerns, are presented below. COAST GUARD'S CENTRAL AUTHORITY AND SUBMERSIBLE TECHNOLOGY There is need for a center of technical expertise regarding submersible applications. This expertise has largely been in place in (de facto) U.S. Coast Guard Headquarters to assist in the certification of the present generators of submersibles. The continuity and enhancement of this Headquarters capability are needed for this unique type of vessel and associated system. rid -I, of A all · To facilitate the maintenance of high standards in submersible vessel design, construction, and operation, the Coast Guard should establish the institutional responsibility in Headquarters~e., responsibility attached to specific personnel for the technical support of tourist submersible certification. This will assist in achieving consistency in the implementation of requirements, the application of engineering judgment, and the determination of tradeoff decisions, while helping to focus attention on the enhancement of safety in these vessels. At present, the Coast Guard has few personnel with technical expertise in tourist submersibles. (Some Coast Guard personnel have such expertise, but duty rotation spreads them too thin.) The Coast ABS Rules were published after completion of this report; earlier proposed classification rules were reviewed by the committee. · X11
Guard needs to develop a better depth of technically capable personnel for use in certification, and inspection of tourist submersibles. The committee recognizes that the number of submersibles under Coast Guard jurisdiction is unlikely to be large enough to justify training a large staff (compared, for example, to the staff needed to support merchant shipping inspection). This is one of the reasons for having a few specialists, located at Headquarters, who may be possibly supplemented by experts from the Navy, ABS, or by consultants. INSPECTION AND TESTS ASTER CONSTRUCTION · Inspection (both initially and periodically through the life of the submersible) is crucial for ensuring safety. The inspection function for vessels is performed by Coast Guard local personnel and ABS surveyors who are well versed in surface vessel technology and inspection standards. These inspectors are working with surface ships on which structural and safety-related problems are commonly encountered and resolved. The technical and operating environments for submersibles present different inspection constraints with less scope for judgment by the local inspector. The inspection program should be defined by the Coast Guard ear) in the design phase of each class of submersible. To provide their expert input, Coast Guard Headquarters personnel, from the ounce designated to provide continuity of expertise in submersible technologies, should participate in the inspections along with the local Coast Guard inspector force. Circularity of cylindrical hulls is a critical factor in safety. It is checked on the construction process, but only on a specific-case basis, in periodic inspections. Inspectors should be alert to signs of damage or distortion and should call for a circularity check if any variation is indicated. A circularity check should be a required part of each 18-month mandated survey or special survey. · The pressure vessel components of a submersible undergo an unusually large number of cycles of pressurization/depressurization. Testing is recommended to establish fatigue failure limits and aging parameters for all new pressure-resistant materials used in tourist submersibles-including especial), at present, acrylic materials to be used in hulls and viewports, and rules should incorporate the required replacement criteria reflecting the results of fatigue tests. · The Coast Guard should establish a firm requirement that rules be applied and enforced consistently, with a formal procedure for approval of variances to the rules. Field inspectors and the local Coast Guard OCMI should be given guidance on which items in the Coast Guard regulations or rules are subject to judgment and require Headquarters' concurrence and which are Ruby "go/no-go." OPERATIONAL CHAIN-OF-COMMAND Particularly during emergency and rescue operations, rapid response and concise communications internal to the organization and external with assisting personnel and organizations are essential to the protection of life. A clearly established, documented, and tested chain-of-command is essential to assuring safety under emergency conditions. Present regulations and guidelines do not provide for documentation and testing within contingency plans. · There is a need to provide clear) defined chain-of-command/decision-making procedures for all operations, especial) for emergency conditions. Periodic exercising of the chain-of-command under simulated emergency conditions should be required. · · x~
SYSTEM REDUNDANCY AND CERTIFICATION TESTING · The tourist submersible operator must ensure a significantly higher level of reliability, compared to most surface vessels, for those systems that are critical to the safety of life. Redundancy of critical components and systems provides one means of increasing reliability. For example, rapid deballasting capability, such as droppable solid ballast weights, would provide backup for the normally used ballast tank system. ADS rules require two independent means of deballasting; the Coast Guard requires that sufficient jettison ballast (i.e., drop weight) must be provided for emergency ascent and that this capability be tested in the water, if possible. The Coast Guard drop weight requirements and the ADS rules may not be consistent and should be clarified. In addition, the committee observed that some deballasting redundant system tests required by the Coast Guard are not being provided by the builders or operators. The Coast Guard, in its certification process, should require that all operating systems--especially those that are safe~y-critical--be functionally tested to design specifications as required in the certification requirements. For example, critical ballast control systems, such as the drop-weight system employed on many submersibles should be tested by dropping the weights in actual operating conditions. The Coast Guard should consider requiring full testing of this system at sea in at least one vessel of each class. There should be a safe, manual alternative means of dropping the weights from the interior of the submersible. In submersibles operating to depths of less than 150 feet, there should also be provision for divers to drop weights from the exterior of the vessel. HAZARDS ANALYSIS AND CERTIFICATION REQUIREMENTS The identification and establishment of hazards to the submersible crew and passengers are basic to the design, certification, test, and inspection plans and processes. This hazard analysis, to be useful, should address all components of systems that the submersible is intended to operate. · The Coast Guard should require that every new design or significant alterations be subjected to a hazard analysis and failure modes and effects analysis. Analyses should encompass the entire marine systemthe support systems, ferry boat, escort boat, emergency rescue capability and facilities, as well as crew training and qualification and passenger management. QUALITY CONTROL RECORD KEEPING · Quality control (QC) standards and documentation are important to safeW. QC includes record keeping. Such record keeping is clearly needed in areas deemed critical to submersible safety. The Coast Guard needs to formalize the QC record keeping system for submersibles, establishing what records are kept, who maintains them, and where. FLAMMABILITY AND FIRE SUPPRESSION · The Coast Guard should include a requirement in their regulations that the selection of materials associated with electrical equipment and wiring and the interior of the submersible should include consideration of flammability properties, including their ease of ignition and flame spread, as well as the composition of combustion products. In its development of these material requirements, the Coast Guard should consider Navy and NASA experience. The design should preclude the use of materials that exhibit low flash or fire points. Flammability considerations should include specif c caution given to passengers entering the submersible to not have any combustible fluids on their person. XIV
The gas Halon is used in current fire suppression systems aboard some (possibly all) tourist submersibles and is accepted as the least risk option in most emergency scenarios considered as possibly occurring on submersibles that can rapidly ascend to the surface. However, Halon could present possible safety and health problems and should be reconsidered by the Coast Guard and ABS. In addition, since Halon contributes to the ozone hole phenomenon, it is likely to be eliminated as an easily available product within a few years. Because nitrogen gas is nontoxic, consideration should be given to the development and testing of a nitrogen-based fre-suppression system as a possible replacement for Halon-based systems. EMERGENCY RESCUE · The Coast Guard should establish a uniform set of vessel design requirements related to the use of emergency rescue equipment. This should include fixed attachment points for lifting tools by another submersible or remotely operated vehicles (ROVs), as well as fittings for connection of hoses from the surface. Consideration should be given to requiring standard hatches (or adaptors) that can be outfitted with mating rings for rescue on at least one hatch. PASSENGER MANAGEMENT · Given the large numbers of passengers and their general unfamiliarity with the submersible environment, passenger management is an important area of operational safety. The Coast Guard (as part of their requirements) should establish planning and training guidelines for passenger management during both normal and emergency operations, covering operations ashore and en route to and from the submersible, as well as underwater. SMALL PASSENGER TOURIST SUBMERSIBLES · There is a category of small, deep-diving submersibles that will be covered only be ABS classification and insurance-related restrictions, not by Coast Guard certification and inspection requirements. These submersibles, carrying six or fewer passengers, come only under current small-boat safety rules, which the committee believes are inadequate to ensure the safety of tourist submersibles. The Coast Guard should establish a special category for these submersibles, to include licensing of the pilots, and closely monitor this emerging segment of the industry. The Coast Guard may require special statutory authority to extend regulatory coverage. Even though the number of submersibles in U.S.-controlled waters is small and not likely to grow dramatically in the near future, the number of passengers involved on an annual basis is quite large. The Coast Guard should issue their revised regulations or standards as soon as possible, since this will improve the dialogue with builders and operators and provide the best possible climate for safe development of this promising new marine industry. Although the operators have had varying degrees of difficulty in complying with classification and certification requirements, the submersible operators observed by the committee have evidently given major consideration to safe operations. This positive safety attitude demonstrated by observed operators is clearly in their own interest, since any accident would be a business catastrophe. As operations expand and become more competitive, however, there will be a tendency to cut corners. As noted earlier, it is possible that older vessels sold into the secondary market might enter service under less technically capable operators who are not as committed to safe operations. These concerns are the driving force behind the committee's recommendations for tightening up controls. Now is the time to take the recommended actions. xv