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Type B Testing.

Section III.B of Option A, provides detailed requirements for (1) examination methods, (2) measurement of the rate of pressure loss, when pressurized, and (3) leakage surveillance by means of permanently installed penetration pressurization system. The allowable leak rate for the total leak rates from the combined Type B and Type C tests is limited to 0.6 La. All periodic Type B tests are required to be performed at a pressure not less than Pa. The acceptance criteria for the combined leakage rate from Type B and Type C tests must be less than 0. 6 La, except as explained in the Type C acceptance criteria.

Type C Tests.

Type C tests are required to be performed by local pressurization of isolation valves as follows:

The pressure shall be applied in the same direction as that when the valve would be required to perform its function, unless it can be determined that the results from the tests for the pressure applied in a different direction will provide equivalent or more conservative results. Each valve to be tested is required to be closed by normal operation without prior exercising (e.g., no tightening of valves after closure by valve motor). Valves pressurized with air or nitrogen are required to be tested at Pa. The valves pressurized with fluid are required to be tested at a pressure not less than 1.10 Pa.

Acceptance Criteria for Type C tests: The combined leakage rate from all Type B and Type C tests is required to be less than 0.6La. However, the leakage from the valves that are sealed with fluid from a seal system may be excluded from the combined leakage rate, provided (a) these valves have been demonstrated to have leakage rates that do not exceed those specified in the TS or associated bases, and (b) the installed isolation seal water system fluid inventory is sufficient to assure the sealing function for at least 30 days at a pressure of 1.10 Pa.

Other Requirements.

Section IV of Option A discusses the additional requirements for pressure tests, such as, when the containment needs to be cut for replacing a steam generator or a reactor vessel head. This requirement is applicable when the licensee has to replace a small size penetration or drill a small hole to add a penetration. After the completion of a specific repair or replacement, the licensee has to determine, which leak rate or structural test would be the most appropriate for confirming the operability of the containment as a whole. The Option also discusses the methods of performing leakage rate testing of containment components, when the containment consists of multiple leakage barriers, or it is subatmospheric. Section V describes the requirements for inspection and summary reports.

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