What should be done immediately after conducting the operating pressure test?

After conducting the operating pressure test, the immediate step is to ensure the safety and integrity of the system. Closing up the gas cock is essential because it prevents any unintended gas flow, which could lead to leaks or hazards. This action maintains the safety of the environment and protects the system's integrity right after the pressure test, especially if the test indicates satisfactory results.

While documenting the test results, inspecting all connections, and calibrating the pressure gauge are also important procedures that should follow the test, closing the gas cock directly addresses safety by controlling the gas supply. Therefore, it prioritizes immediate action necessary after pressure testing.