What method is used to test the porosity of hair?

The porosity of hair refers to its ability to absorb moisture, which is mainly influenced by the condition of the cuticle layer. One established method to test hair porosity is the wet test. This involves taking a strand of hair and observing how quickly it absorbs water. High porosity hair tends to absorb water quickly due to gaps or tears in the cuticle, while low porosity hair may repel water initially.

The pull test is primarily used to assess the strength and elasticity of hair rather than its porosity. The shine test evaluates the reflectiveness and overall health of the hair, but it doesn't measure porosity. Backcombing is a styling technique and doesn’t provide pertinent information about the hair's ability to retain moisture.