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2 EXISTING PROCEDURES FOR CLASSIEICATION AND CERlIEICATION OF TOURIST SUBMERSIBLES The U.S. Code of Federal Regulations (CFR) requires that vessels built in the United States or operating in U.S. waters be certificated by the Coast Guard as being seaworthy and meeting the requirements for safety at sea as well as other regulations stipulated by law. Before they will issue insurance, the insurers require that a vessel meet standards for construction and operation established by the American Bureau of Shipping (A~S) or one of the other recognized classification agencies, e.g., Lloyd's Register of Shipping (U.K) or Det norske Veritas (DnV) (Norway). When a vessel meets these standards established by a classification society, it is deemed to be "classed." THAWS, there are two important termscertification and classipcanon~hich are sometimes used interchangeably, resulting in some confusion. While there is some overlapping of the plan review and inspections, essentially the U.S. Coast Guard is responsible for certificating that the vessel and every aspect of its operation meet all federal regulations. Separately, the ABS or other classification agency must state that the vessel complies with its rules (which underwriters interpret as being that the vessel is structurally wed' {lP.RiD11Pfl Anti heist anA will he an ~ ~ ~ _ ~ ~ . . _ __ __ _ ~ V ~^ ~ ~~ ,' BAA Van "A! acceptable insurance risk). In order to classify a vessel, the ABS has established rules to be followed during design and construction.) In the case of submersibles, these rules are based in part on the standards established by the American Society of Mechanical Engineers (ASME) governing Pressure Vessels for Human Occupancy (PVHO-11.2 While the Coast Guard does not require cln.~.Rif;~tiOn it {MOPE ,lcH REP HARE A ~ ~ ~ ~ ^~ ~ ~ __ ~^ ~ _~V~ ~A&~ I TVO ~~ a ~ _ ~ ~ rules and AbiM~ standards as guides when evaluating vessels for certification. In both organizations, the number of technical personnel involved in certification and classification of submersibles is small. Since relatively few tourist submersibles have been certificated or classified, the procedures and documentation have been developed with the cooperation of the builders, the ABS, and the Coast Guard. All of the participants report that they have learned from each other and recognize the importance of each player. The interaction has caused them all to have a healthy mutual respect, which is an ideal situation. A recent paper by Coast Guard officers describes the history and current procedures for regulation of tourist submersibles.3 The details of the Coast Guard plan review for the ATLANTIS III submersible are described in a paper published by the Society of Naval Architects and Marine Engineers (SNAME).4 In addition to reviewing the design and engineering of the vessel, both the Coast Guard and the classification societies routinely conduct inspections during the construction and at regular intervals during the operation of each vessel. Although technical expertise is concentrated in the headquarters of both ABS and the Coast Guard, inspection of the vessels is conducted through regional offices headed by senior personnel. In general, contact with the organization is through the local inspection offices for all matters; this establishes a single point of contact for a given operation or vessel. ABS will be used throughout as the U.S. example of a classification society, of which there are some 17 worldwide. 14

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15 RULES AND REGULATIONS The Coast Guard has taken a systems approach to certificating submersibles, evaluating the combined design, operation, dive site, and operator qualifications from the conceptual stages through the initial operations. As noted previously, the basic requirements for certification are promulgated in the Code of Federal Regulations under Titles 33 and 46, which contain regulations for many different subjects. The sections that apply to passenger-carrying submersibles (46 CFR, Subchapter 1) are referenced in a set of draft guidelines that will be issued by the Coast Guard as a Navigation and Inspection Circular (NAVIC ).s This draft circular (attached as Appendix A) is thorough and contains amplifying remarks that should prove useful to anyone working in the field. ABS has similar documents available to anyone who requests them. These documents are based on extensive Navy experience with submarine design, with contributions from industry technical societies, especially SNAME and ASME. DESIGN Design of submersibles is presently guided entirely by the ABS rules (see reference 1~. This comprehensive new document contains detailed information on the design and construction of submersibles. The requirements are in accordance with good engineering practice and have been proven by many tests and experiments. Finite element analysis for structures is a recognized stress analysis method when existing rules are not directly applicable. For most calculations, the formulas to be used are specified in the document. The requirements for hull penetrations are specified in great detail, particularly those for viewports and acrylic domes. The new book of rules results from and reflects the experience gained while designing and building a wide range of submersibles, including some newer ones. PLAN REVIEW Engineering computations and plans are prepared by the vessel designer or the shipbuilder. Normally, they would then be presented to the local offices of the Coast Guard (specifically, to the Officer in Charge of Marine Inspection [OCMI]) and the ABS, whichif the plans were for conventional surface vessels~ould approve or disapprove them. Tourist submersibles are considered to be distinctly different and therefore require special attention. Before plans are submitted, the Coast Guard requires that a proposal describing the concept of each individual submersible to be built (including the draft operations and safety plan for the entire system) be submitted to the Marine Technical and Hazardous Materials Division (G-MTH) at Coast Guard Headquarters. Once this system concept has been reviewed and accepted (the process is referred to as a System concept reviews), the detailed plan is prepared and submitted, with the application for inspection, to the OCMI. The OCMI then forwards his set of plans (in most cases *A Navigation and Inspection Circular (NAVIC) is not part of the CFB. It provides guidance for implementing vessel inspection laws and regulation, but is not part of the regulation. * * The Coast Guard will accept design standards imposed by other classification societies only if they can demonstrate equivalence with ABS rules. **$Plans include pressure hull strength calculations; construction tolerances; life support and vital system details: buovancv. stability, and damage calculations; material identification; and power and control systems. ~. ~~ ~~ v~~~

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16 without reviews to the Marine Safety Center (G-MSC) in Washington, D.C. (not located at Coast Guard Headquarters), which is the appropriate technical office for review and comment or approval. The boat designer also forwards the computations and plans directly to ABS headquarters for action by the technical staff, and they are then sent to the ABS surveyor. In both cases, review consists of an engineering investigation, which includes analyses of the method and accuracy of any calculations and the plan's clarity and completeness. When approved for construction, the plans and computations are returned via the local inspection offices to the designer, who will in turn issue them to the shipbuilder. Since the technical offices in the headquarters are small, a few people review the documents for all submersibles. However, these persons are normally Coast Guard commissioned officers who change jobs and locations frequently (every two to four years). This arrangement cannot ensure that there will be continuity of knowledge and policies and their application. APPLICABILITY Federal regulations differ by size and class of vessel. (Table 2-1 lists the subchapters of the CFRs relevant to the Coast Guard.) Most passenger-carrying submersibles are in the category of "small passenger vessels." These are defined as being less than 100 gross tons, carrying more than sex passengers. They must comply with applicable sections of 46 CF~ Subchapter T. "Small Passenger Vesselsn; Subchapter S. "Subdivision and Stabilityn; and Subchapter B. "Merchant Marine Officers and Seamen." Compliance with 33 CFR Part 155, foil Pollution Prevention Regulations for Vessels," and 33 CF~ Part 159, "Marine Sanitation Devices," is also required. In addition, the COTP may impose special operating requirements under authority of 33 USC Chapter 25, "Ports and Waterways Safety Program," and 33 CF1( Part 160, "Ports and Waterways Safet~General." Concerns of the COTP include special operational restrictions, navigational safety, and port security considerations. Submersibles carrying six or fewer passengers are categorized as ~Uninspected Vessels." Although not subject to inspection, they must still meet certain regulations regarding oil pollution, sanitation, boating safety, and manning requirements. Thus, the Coast Guard does have a measure of control over the operation of even this type of vessel, although the requirements do not address this size submersible and do not provide for periodic inspection after the vessel is manufactured. Again, the COTP may place operating restrictions, if the operation is deemed unsafe. A senior officer who has questions of a technical nature that exceed his or her expertise with respect to submersibles can contact the OCMI for consultation. (In many ports today, it should be noted, a single Coast Guard officer is both COTP and OCMI.) As a minimum, permission to operate will be granted only if the vessel has been designed and built in accordance with recognized industry standards. At this time the recognized standards are the classification societies' rules and technical society standards. The situation with regard to research and work submersibles is not within the charter of this committee. However, there are concerns about deep-diving work submersibles that have recently been acquired for tourist use and are currently being classed for that purpose through ABS. At this writing, it is unclear what position will be taken regarding the possible aerating of these boats due to their age, maintenance practices, and proposed modifications (such as adding viewports by penetrating the hull). Vessels of 100 or more gross tons are in another category. At the present time, there are no U.S. passenger-carrying submersibles in this size category. When and if they are built, they will be subject to the requirements of 46 CFR Subchapter H. "Passenger Vessels," rather than 46 CFEt Subchapter T. "Small Passenger Vessels." Recreational submersibles are vessels built primarily for recreational use by individuals. At the present time, the only requirements are the rules for boating safety, 33 CFR Parts 173-183 of Subchapter S. The COTP may impose restrictions if there are concerns about the safety of the operators involved. *The operator may also appeal the COTP's decisions up through the chain of command to Headquartem.

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17 Foreign submersibles (of any size) are ordinarily certificated by the country of registry. This certification is generally recognized by the Coast Guard for vessels other than submersibles. However, because of the uncertain nature of the hazards involved, the OCMI will not permit submersible operation until there is a valid U.S. Certificate of Inspection (COI) issued or Safety of Life at Sea (SOLAS) Passenger Ship Safety Certificate issued. Both Lloyd's Register and Det norske Veritas (DnV) have classed TABLE 2-1 CF~ Coast Guard Regulations Applicable to Tourist Submersibles Title 33Navigation and Navigable Waters Subchapter A - General Subchapter O - Pollution Subchapter P - Ports and Waterways SafeW Subchapter S - Boating Safety Title 46Shipping Subchapter A - Procedures Applicable to the Public Subchapter B - Merchant Marine Officers and Seamen Subchapter C- Uninspected Vessels Subchapter F - Marine Engineering Subchapter H - Passenger Vessels Subchapter J - Electrical Engineering Subchapter S - Subdivision and Stability Subchapter T- Small Passenger Vessels (Under 100 Gross Tons) manned submersibles.6 With the construction of at least eight tourist submersibles in Europ~two of which are presently being classed by DnV it is desirable for the Coast Guard to maintain a dialogue with classification societies to encourage consistency in the interpretation of various rules. FINDINGS AND CONCLUSIONS REGARDING CLASSIFICATION AND CERTIFICATION The ABS rules for passenger-carrying submersibles that were published in 1990 and the proposed Coast Guard guidelines (Appendix A) for certification of passenger submersibles that led to them were reviewed by the committee. These documents appeared to be adequate, and provided sufficient feedback to recognize past deficiencies and account for lessons learned through operational experience. In summary, the committee has not identified anything of significance regarding the rules for certificating these vessels that the Coast Guard has not already identified and focused on. The latter case is subject to an onboard control verification inspection by the Coast Guard to verily that SOLAS requirements have been met. * ~ Unpublished data provided to the committee by DnV, Houston, July 28, 1989.

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18 There is concern about the safety and the lack of safety-related regulation of submersibles designed to carry sex or fewer passengers, which are being designed and/or converted for tourist use. Present Coast Guard rules regarding tourist submersibles (46 CFR Subchapter T) should be amended to include the Subchapter C, nUninspected Vessel, category of boats. Statutory authority may be required to extend this authority. With approximately 6 already under ABS classification and at least 40 others that could be purchased and modified, there is significant potential for future hazard. Discussions among ABS and other major classification societies would be beneficial since several classification societies have been engaged in development of rules applicable to submersibles for industrial use, or more recently, tourist submersibles under construction. In the absence of direct application of Coast Guard rules, the basic safety of these smaller submersibles (6 passengers or less) can be assured only through the classification societies, and this will place a special burden on direct operational control by the COTPs. r