The strength test is part of the TRGI measurements. The strength test is carried out during the shell construction phase. Before plastering or covering, gas pipes are checked for the strength of the material used and the durability of the joints. The newly installed pipes—without fittings and gas appliances—are tested at a test pressure of 1,000 hPa. Air or an inert gas is used as the test medium. The pressure must not drop within 10 minutes. The measuring device must have a resolution of at least 0.1 bar. An overview of all ecom pressure measuring devices shows which device is suitable for which application.