Washington Gas Piping Test Affidavit is a document used by Washington Gas to verify that a gas piping system has been tested and is safe to use. The affidavit is submitted by the gas contractor or installer after testing and installing a gas piping system. There are two types of Washington Gas Piping Test Affidavits: Type A and Type B. Type A Washington Gas Piping Test Affidavit is used to attest that a gas piping system has been tested with a pressure gauge and proof tested. This type of affidavit is required after installing new gas piping or replacing existing gas piping. Type B Washington Gas Piping Test Affidavit is used to attest that a gas piping system has been tested with a combustion analyzer and proof tested. This type of affidavit is required when installing a new gas appliance, such as a furnace, water heater, or fireplace. Both types of Washington Gas Piping Test Affidavits must include the contractor or installer's name, address, and license number, as well as the date of the testing and the results of the test. The affidavits must also include the name and address of the customer, a description of the system being tested, and a signature from the contractor or installer.