1.1 This test method covers the evaluation of gaskets under corrosive conditions at varying temperature and pressure levels. The test unit may be glass lined if the flanges are sufficiently plane (industry accepted), thus providing resistance to all chemicals, except hydrofluoric acid, from cryogenic temperatures to 260°C (500°F) at pressures from full vacuum to the allowable pressure rating of the unit, or made of other suitable material. The test unit described (Fig. 1) has an internal design pressure rating of 1034 kPa (150 psi) at 260°C (500°F).