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APPENDIX B SUGGESTED INSPECTION REQUIREMENTS This appendix describes in some detail a suggested inspection plan developed by the committee. It is based on existing Coast Guard inspection procedures but augmented with experience from U.S. Navy and commercial research submersibles, which would address the particular requirements of the tourist submersible arena. As a first step, the Coast Guard could require that the vessel designer, in conjunction with the intended operator, obtain Coast Guard approval of a certification scope definition as part of the initial approval process. This document would provide information on how the submersible's design meets the regulations. In addition, the initial approval effort might include the development of a periodic inspection plan that defines, in detail, program areas that will be reviewed at prescribed time intervals. Such an inspection plan should provide local inspectors with information on both the scope of the inspections and the quality assurance documentation necessary for sustaining approval. It should address the four major certification concerns: design, construction, operation, and trainin~even though the majority of the design and construction effort will have been completed before periodic inspections begin. Ideally, such a plan should be the result of a joint effort by the designers, operators, and the Coast Guard, with an understanding that each program and hardware combination is likely to have unique characteristics. The plan should result from a careful review of the initial design approval requirements and an analysis of how these requirements have been met by the equipment in question. A hazard analysis in some form (see Chapter 4) is likely to be necessary in order to ensure that the plan assigns the appropriate significance to various design details. Care must be taken to ensure that the plan is realistic; the goal is to ensure safe operations to the greatest extent practical without unnecessarily burdening the operators and encouraging them to focus attention on the primary safety concern. Operational judgment should play an important role in defining the requirements. Any inspection plan should be specific to the design in question and list those items subject to periodic review along with a justification for their inclusion as required to clarify the conditions necessary for approval. As an example, it is reasonable to expect two independent means for determining submarine depth to be a regulation requirement. The submersible might have more than two depth-indicating devices installed but, for maintenance reasons, the operators may wish that only two simple, reliable mechanical pressure gauges be considered mandatory. This is likely to be acceptable only if at least one of these gauges is the primary device used by the pilot for determining depth. Therefore, their mounting location and the wording of the operator's manual must be considered as part of their approval process. Also, for safety purposes, it may be possible to show that the accuracy of these gauges is not critical except at maximum allowable depth and, therefore, the acceptance criteria may involve only a single point calibration. The inspection plan might therefore specify a requirement for review of two external pressure gauges mounted within plain sight of the pilot, marked with a calibrated point indicating maximum operational depth and specified for use by the pilot in the operator's manual. ~ c7 , Experienced engineering and 94

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The original approval process is likely to include the requirement for operational definitions such as those that might be included in a management plan, operations manual, or maintenance manual. The existence of these manuals may be required and their contents subject to approval. Periodic inspections would therefore need to determine if the required, approved manuals are in use. The obvious method is via direct observation of operations, but this is rarely possible during scheduled inspection periods and often is not adequately quantitative. A better alternative is to ensure that the approved procedures generate qualitative documentation that can be reviewed by inspectors or auditors. Daily check sheets, work logs, personnel training records, failure reports, inspection/test reports, receipt inspection records, and records of replacement or repair are examples of this type of documentation. The review of records of this type should be specifically required by the periodic inspection plan. Their existence provides a significant indication to the inspectors that proper procedures are being followed and their content provides objective information on machinery and personnel histories. An approved operations procedure will undoubtedly specify a submersible pilot training program and pilot qualification maintenance procedures. Here also, there should be a requirement to generate defined documents that can be reviewed by the inspectors. Examples of such documents are the results of suitable medical examinations, records indicating successful completion of training milestones and a pilot's log book. This latter item should record diving experience as well as participation in required safety and emergency drills. The inspection plan must also specify the documentation necessary to provide objective quality evidence of acceptable conformity to approved specifications. Specifications are the standards to which equipment and components are purchased, installed, tested, and maintained. They are a primary line of defense against equipment failures. An inspector may be presented with a detailed piping pressure test report generated as the result of a maintenance manual requirement. The validity and, therefore, usefulness of this report depend upon the test specifications, and the test documentation must include evidence that the specifications were met. The fact that required maintenance was performed and a pressure test conducted is useful information but it is equally important to know that the test pressure was correct for the application and that the gauges were calibrated in the way that the specifications are likely to require. A typical periodic inspection will follow the procedures agreed upon during the generation of the inspection plan and involve both observational inspection and auditing functions. The inspections allow verification of equipment condition and witnessing of prescribed tests in a manner similar to that done during the construction and trials phase. Auditing involves review of the documentation generated in accordance with the prescribed operational procedures. As an example, an inspector may visually survey the pressure hull and witness a prescribed test designed to demonstrate acceptable hatch operation. He may then ask to see the hatch maintenance records required as part of the necessary hatch maintenance procedures in the approved maintenance manual. These records are likely to document timely replacement of the primary hatch O-ring using a record-of-repair form. It must include evidence of adherence to the proper procurement and handling specifications as well as a receipt inspection report for the O-ring itself A hatch fit test may have been required, and if so, the test procedures and results must be documented on a suitable test form, including the pass/fail criteria and an analysis of the results by qualified persons. This is similar to present Coast Guard inspection procedures, except that the inspection plan provides the local inspector with considerably more information on how the design is intended to meet the regulations and how its condition and method of operation can be evaluated. At no place in the above example is the inspector likely to be required to make a critical technical judgment. The hatch requirements have been documented and approved in advance, including pass/fail criteria for the general inspection, which are determined at the time of design. The inspector is simply reviewing the objective evidence available as a result of the requirements. For the most part, this evidence will be generated in advance of the Inspection, so mere snouts ne no question about the outcome. If a problem is discovered, it is likely to indicate two deficiencies: a defective piece of hardware and a poorly designed or implemented procedure . . - .. . .. . that allowed the defect to go undetected prior to the inspection. Both need to be corrected. As is the case with the Coast Guard's present method of operation, inspection timing should be fixed at agreed-upon intervals with unannounced inspections allowable. The length of the fixed intervals must be such that an inspection will occur before serious system degradation is likely to occur under 95

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probable maintenance conditions. This time interval should be determined by experience with systems of this type; it may vary with the particular hardware involved and the operational location. An initial period of between 3 and 6 months is recommended, with the proviso that, at the Coast Guard's discretion, it may be increased following some specified length of uninterrupted operational experience. This initial short time period accomplishes three things: (1) it allows a more controlled initial evaluation of the hardware and operating personnel on the part of the Coast Guard; (2) it forces the operators to maintain adequate awareness of the approval requirements during the operational startup period; (3) and it provides the operators with a reasonable time interval for their education in the area of maintaining the Coast Guard's approval. Once the operators have demonstrated an understanding of the requirements and established a history of acceptable performance, it should be possible to decrease the frequency of scheduled inspections. The Coast Guard presently documents inspection/audit results in a prescribed manner along with the corrective action required and the allowed time period. Generally, deficiencies must be corrected by meeting the approved requirements. There will be instances where this is not possible in a timely manner or where good judgment indicates that another course of action may be more appropriate. These cases should require approval of a waiver requested through a process independent of the inspection. Again the inspector should not be required to make technical judgments. Organized, periodic inspections are an important aspect of ongoing operations. The designs of tourist submersibles and their method of operation can be sufficiently unique to require a high degree of detailed knowledge on the part of an inspector to ensure an adequate safety review. This requirement can be met by providing a detailed inspection plan generated as part of the initial approval process and encompassing the program's equipment, operational procedures, and training programs. The inspectors should rarely be required to make technical judgments; instead, the inspection plan should contain the necessary pass/fail criteria for each approved item or system. As with the initial system approval, periodic inspections represent a major effort on the part of both the Coast Guard and the operators. Great care must be taken to limit the inspection criteria to those items and procedures of real importance to the safety of the passengers and operational personnel. 96