ISO 16603:2004 describes a laboratory test method for measuring the penetration resistance of clothing materials to blood and body fluids. This test method uses synthetic blood, which is put into contact with material specimens over a length of time (6 seconds), at specified set of conditions using the ISO 13994 apparatus. Note that this version has undergone official review by The International Organization for Standardization.

This test doesn’t always produce accurate results when testing protective clothing materials which have inner liners of a thick material, such as fleece.

It is emphasized that the test does not necessarily simulate conditions to which clothing materials are likely to be exposed in practice. The use of test data should therefore be restricted to broad comparative assessment of such material according to their synthetic blood penetration resistance characteristics. Testing prior to degradation by physical, chemical, and thermal stresses which could negatively impact the performance of the protective barrier, could lead to a false sense of security, and accordingly diminish the value and reliability of this test.