New York City Gas Code Practice Test

What is the role of a manometer or test gauge during tests?

To measure electrical resistance in piping.

To check color of combustion air.

To verify the purge length of the line.

To measure gas pressure and verify it matches the required test pressures.

During gas-system testing, a manometer or test gauge is used to measure the gas pressure in the piping and verify it matches the required test pressures. It shows you the exact pressure at the test point, so you can confirm the system can hold the specified pressure without leaking. By monitoring the reading over the test duration, you can tell if the pressure remains steady or if there’s a drop that indicates a leak that must be found and repaired. The gauge should be calibrated and read in the proper units for the test (often inches of water column for low-pressure gas piping).

The other options don’t fit this role: measuring electrical resistance is done with an ohmmeter, not a pressure gauge; checking the color of combustion air isn’t about pressure measurement; and purge length is a procedural aspect of the test, not something you verify with a pressure gauge.