ASTM E331

ASTM E331 is the standard test method for water penetration of exterior windows, skylights, doors and curtain walls by uniform static air pressures differential.  The ASTM E331 covers the determination of the resistance of exterior windows, curtain walls, skylights and doors to water  penetration when water is applied to the outdoor face and exposed edges simultaneously with a uniform static air pressure at the outdoor face – higher than the pressure at the indoor face.