I see no one has answered. You will need to be more specific as to what the service is for and under which code the pipeline is governed.
Specifications & procedures are separate documents. Your project specification will contain the requirements for meeting the governing code(s) as well as any company specific requirements. The procedure will then be developed based on meeting the project specification.
I am not aware of any place to find off the shelf specifications or procedures for leak testing, however there are many companies that specialize in precommissioning type work such as pressure testing and leak testing. They would probably be your best bet.
Greg Lamberson, BS, MBA
Consultant - Upstream Energy
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