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REVIEW AND ANALYSIS OF EXISTING SYSTEMS AND AGENTS Historically, verification programs have been insti- tuted as a result of catastrophes to assure the adequacy and safety of hazardous structures or equipment. They provide the basis for obtaining insurance for liability or loss, and for obtaining government approval or licens- ing for construction and operations. Examples are: 0 Ship Classification: Originally instituted for insurance purposes by Lloyd's of London and by the Ship Master's Association (predecessor of the American Bureau of Shipping [ABS]); and, 0 The Boiler and Pressure Vessel Code: Originally instituted for insurance purposes by the American Society of Mechanical Engineers (ASME). In both cases, verification systems have been adopted by various governmental agencies to assist in fulfilling their regulatory responsibilities. The panel reviewed several verification systems cur- rently used in the United States and other countries. In addition, the panel reviewed the three optional verifica- tion procedures considered in detail by the Aerospace Corporation in their report to the USGS. The following verification systems were considered by the panel: Present USGS system for offshore platforms; Present internal system for offshore platforms used by many elements of U.S. industry; Present British system for offshore platforms; Present Norwegian system for offshore platforms; Present U.S. Coast Guard (USCG) system for ships and mobile offshore rigs; 15

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16 Present Federal Aviation Administration (FAA) system for civil aircraft; and, Three verification options proposed for USGS consideration by the Aerospace Corporation. The panel also considered, in less depth, the systems used by the U.S. Army Corps of Engineers for dams and by the U.S. Nuclear Regulatory Commission for power reactors. Present USGS System for Offshore Platforms The USGS system is based on OCS Order No. 8. It allows for differing environmental conditions encountered in the Gulf of Mexico and the Pacific Coast offshore areas, but in each case, the Order requires that the structure be designed to withstand the maximum operational and environmental loads expected to be imposed on it.11 It also requires that the adequacy of the design be certified by a registered pro- fessional engineer. OCS Order No. 8 calls for personnel from USGS regional offices to review the general arrange- ment of the structure, the sizes of the primary members, and the anticipated operational and environmental loads. Internal industry reviews, which are discussed in the next section, are not necessarily submitted with the documenta- tion to USGS. However, such reviews are used by the certi- fying professional engineer to help in an evaluation of the adequacy of the design. The USGS has evolved a system for issuing regulations. It solicits industry, government, and the public by publi- cation of a proposed regulation in the Federal Register and requesting comments. USGS reacts to the comments prior to final promulgation of the regulation through the Federal Register. As presently constituted and performed, the USGS system cannot assure the structural integrity of offshore oil and gas platforms in the harsher environments of the Arctic and Alaskan waters. It will take time to codify the experience being gained from other harsh environments, such as the North Sea, and it will require more experience and knowledgeable staff to apply it. Furthermore, although

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17 the USGS system invites public participation, it does not provide for an effective appeals route. The lack of adequate criteria for the registered professional engineer who certifies the platform, further weakens the the credibility of the USGS procedure insofar as the public is concerned. The present USGS system has a fail- ure-reporting and analysis function, but due to lack of staff, the analysis function is not strongly implemented. Formalized accident investigation and review, and system audit functions are not included. Present Industry System of Design and Construction Review The internal design review is conducted by specialists who have taken part in the actual design and construction work. The reviewers determine whether the design and con- struction meet accepted industry practice, the customers' requirements, and applicable codes, standards and practices. Independent re-calculations or re-analyses of the structure may or may not be conducted. The process is monitored and disputes are resolved by high level company officials. In Wartelle's paper, prepared for the panel, a schedule for a typical industry review is described, and appears in Appendix C. In view of the public's wariness toward industry to- day, it would be naive to assume that the industry verifi- cation system would sufficiently assure the public and the Congress as to the structural integrity of offshore plat- forms and to the safeguards and precautions that are being exercised for protecting human life and the environment. However, the industry system undoubtedly uses its tech- nical personnel more efficiently and effectively. British System for Certification of Offshore Platforms In Great Britain, the Department of Energy (DOE) is responsible for establishing certification requirements. The basic statutory regulations are amplified in Guidance on Design and Construction of Offshore Installation, pub- lished by the DOE in 1974.1*Certifications and periodic recertifications of offshore structures are conducted by five ship classifications societies: Lloyd's Register of Shipping; Det norske Veritas; Bureau Veritas; American Bureau of Shipping; and Germanischer Lloyds. These organiza- tions are appointed by the DOE to provide a "Certificate of Fitness" for each installation.

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18 In addition, the DOE is presently appointing two additional certifying authorities which are a consortia of English and Scottish-based consulting firms. The certifying authorities have established their own rules and requirements within the general bounds of the govern- ment's statutory and guidelines regulations. Such rules provide the principal technical documentation in all areas except those dealing with environmental concerns. The rules are based upon experience as well as documents such as API-RP2A, the accepted British National Codes and Standards, and other widely-accepted codes and standards. Environmental conditions are described by the British weather service. The system, based on observations of panel members, has negative characteristics. The Lloyd's or DNV review procedures (principal ones used) require costly indepen- dent re-computation of structural conditions. The DOE is reported to lack sufficient experienced competent personnel. As a result, the DOE cannot provide a strong monitoring activity nor perform an effective updating of regulations that stay abreast of technological advances. In addition, the British system does not provide an effec- tive appeal route for disputes between the operator and the certifying authority. The highly structured and detailed content of the rules of the British system, and its lack of flexibility discourages the introduction of new technology, and makes it difficult to design prudently and cost-effectively. The British system provides for an effective use of tech- nical manpower by the verification agents (except for the structural re^-analysis in the implementation steps of the system), but does not provide an appeal route or invite public participation. Norwegian System for Certification of Offshore Platforms The Norwegian system is similar to the British for certification and periodic recertification, except that less authority is delegated to the certifying authorities. The Norwegian Petroleum Department (NPD) is responsible for verification. The primary certifying authorities are Det norske Veritas and Dr. Aas Jacobsen and Associates (A-J). The NPD also enforces rather detailed occupational safety regulations, comparable to those of the U.S. Occupational Safety and Health Administration. While the NPD also provides environmental design information, the

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19 primary structural rules are set by the certifying authori- ties. These rules, like those in Britian, are based on DNV experience, FIP recommendations, API-RP2A, applicable government standards, and other widely-accepted codes and standards. The DNV and A-J reviews also include an inde- pendent re-computation of the structural analysis. The NPD is better staffed than the DOE and thus is able to maintain a greater degree of monitoring and updating of regulations than the DOE. The Norwegian system has demonstrated in practice con- siderable flexibility primarily because of the effective use of its personnel. Nevertheless, because it is highly structured and the rules are extremely detailed, the adop- tion of new technology may be difficult. The Norwegian system does not provide for public input. The U.S. Coast Guard System for Certifying Ships and Mobile Offshore Rigs The United States Coast Guard (USCG) has statutory responsibility for the certifying and periodic recertifi- cation of ships and mobile offshore rigs before these are fixed in place. The USCG has a strong in-house technical capability and provides detailed regulations and rules under which ships and mobile rigs are certified. These rules are developed through the Federal Register process. The American Bureau of Shipping (ABS)is authorized by statute to provide certain structural certifications based upon USCG and ABS rules. The USCG participates in the development of ABS rules. The ABS structural rules for ships are the result of over a century of operating experience as well as technical analyses. As is the case for DNV, Lloyd's and A-J, the ABS also depends on an independent re-analysis of the structure in its review. The environmental conditions are specified for ships and will vary depending on the "class" to which they are certified. The USCG operates a continuous mointoring, investigation, and review system to provide data about failure and accidents. Major accidents are formally investigated by USCG teams and their findings are reviewed by the National Transportation Safety Board (NTSB) to deter- mine probable cause.

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20 FAA System The Federal Aviation Administration (FAA) has the statutory authority for certifying the airworthiness (structural)and operational safety of civil aircraft operating in the United States.13 FAA rules and regula- tions are established after publication in the Federal Register. The technical base for the certification pro- cess of FAA is derived from in-house technical personnel and benefits from the expertise of the National Aeronau- tics and Space Administration (NASA) and the Department of Defense (DOD). In the FAA system, certification of a particular type of aircraft begins with a certification plan developed by industry based on FAA rules. Following approval of the plan by the FAA (often after modification), implementation is accomplished by Designated Engineering Representatives (DERs) and Designated Manufacturing Inspec- tion Representatives (DMIRs) with the FAA monitoring and auditing. DERs and DMIRs are nominated by industrial employers and approved by the FAA. They do not review or inspect work for which they have been responsible.* The DERs and DMIRs review the design, quality control, and manufacturing inspection activities on those aircraft-types for which they have been qualified by the FAA. Their work is monitored and audited by FAA technical personnel. The FAA operates an effective failure reporting and analysis system that provides information for improved regulations and for the determination of recommended or mandatory aircraft modification requirements. All major accidents are investigated by the FAA in conjunction with the NTSB. The findings of probable accident causes are then published by the NTSB. The results of these investi- gations and reviews are utilized in a continuing process of updating the regulations and improving airworthiness. Proposed Aerospace Options The three options considered by the Aerospace Corpora- tion for USGS implementation are basically identical, ex- cept for the affiliation of the personnel performing the verification functions. Possible types of personnel and their affiliations are: employees of classification *USGS places similar limits in their definition of third- party certification as published in the Federal Register, Jan. 29, 1976, and quoted herein on page 7.

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21 societies, such as ABS, DNV, or Lloyd's; teams of personnel from offshore engineering, design, or construction firms who divest themselves of other offshore business to avoid conflict of interest; and designated representatives from industry. The Aerospace Corporation recommends a verification procedure in which USGS personnel are charged with the development of the verification plan. The extent of the technical review undertaken through verification would depend on the degree of experience/knowledge of the design and construction procedures proposed and the expected environmental loading. In the Aerospace study, offshore structures are subdivided into six classes, based on com- binations of existing, extended, or new technology and known or unknown environments.11* These classes are: Class A Units or structures of proven design in a known environment* Class B Units or structures of proven design in an unknown environment** Class C Units or structures of extended design in a known environment Class D Units or structures of extended design in an unknown environment Class E Units or structures of new design in a known environment \ Class F Units or structures of new design in an unknown environment The environmental conditions would be determined from a data base prepared and evaluated for the USGS by a con- tractor. The design and construction rules and regulations would be derived from existing applicable rules and codes. *Known environment is that for which nominal and extreme wave and wind loads can be predicted with acceptable accuracy and seabed geotechnical characteristics are known. **Unknown environment is that for which the above predictions are not substantiated with sufficient data and/or seabed geotechnical characteristics are not well known (latter applicable to seabed fixed units).

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22 These, according to the Aerospace study, would be reviewed and augmented to cover harsh environments and all current design practices. The rules would be promulgated through the Federal Register. The NRC panel notes that provisions were not included in the proposed Aerospace procedure for reporting and analyzing failures, investigating and reviewing accidents, auditing the entire process, or including such data and evaluations in the regulations and rules. As described by Aerospace, the process appears to this panel to be quite detailed and rigid. The only flexibility provided is the choice among the six classes of verification. An appeals route is provided by which the USGS regional and area offices could resolve disputes. No reference is made to appeals by industry. The panel identified a set of criteria as a result of its examination of each of the foregoing verification sys- tems. Ideally, the verification should: 0 Provide the public and the Congress with added assurance that industry development of the DCS is being pursued in an environmentally accept- able manner; 0 Accommodate and encourage new technology, avoiding over-dependence on codes instead of good engineering; 0 Be flexible and adaptable to frontier-area operations; 0 Provide for an appeal route in contested determinations; 0 Avoid introduction of undue delays; 0 Provide for the most effective use of personnel with experience in design, fab- rication, and installation of OCS structures; 0 Minimize disruption to the USGS and industry operations; 0 Provide time for the USGS to acquire and train staff; and, 0 Facilitate "phased" implementation.

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23 The panel determined that none of the existing systems entirely meet the basic criteria and institutional require- ments for a verification system that would effectively assure the public and the Congress of the structural inte- grity of the new platforms. Continuation of the USGS system would be least disruptive for both the USGS and the off- shore industry. The introduction of the other systems would be disruptive, at least temporarily, since all would cause marked changes from the present practice. The British and Norwegian systems would provide less disruption to industry (except for the associated acquisition of strong technical personnel by the government) since much of the U.S. off- shore industry has already worked with one or both of these systems in the North Sea. As now constituted, all of the systems are sufficiently structured to recognize the time required to acquire and train personnel in a phased manner.