ISO 4920

Textile fabrics - Determination of resistance to surface wetting (spray test)

ISO 4920:2012 specifies a spray test method for determining the resistance of any fabric, which might or might not have been given a water‑resistant or water‑repellent finish, to surface wetting by water.

It is not intended for use in predicting the rain-penetration resistance of fabrics, since it does not measure penetration of water through the fabric.