ISO 6530:2005 specifies a test method for the measurement of indices of penetration, absorption and repellency for protective clothing materials against liquid chemicals, mainly chemicals of low volatility.

Two levels of the potential performance of materials are assessed by this method of testing to meet with possible requirements for protection against the following:

1. deposition on the surface of a material, at minimal pressure, of spray droplets up to coalescence or occasional small drips;
2. contamination by a single low-volume splash or low-pressure jet, allowing sufficient time to divest the clothing or take other action as necessary to eliminate any hazard to the wearer from chemical retained by the protective garment, or, in circumstances where pressure is applied to liquid contaminants on the surface of the clothing material as a result of natural movements of the wearer (flexing of contaminated areas of clothing at arms, knees, shoulders) and contact with contaminated surfaces (e.g. walking through sprayed foliage).