Porosity determines processing time and proper perm solution. This statement is:

• A. True
• B. False
• C. Only Affects Color
• D. Only Affects Curl

Answer: (A)

Porosity tells you how easily hair absorbs moisture and chemicals, which directly affects how quickly the waving solution can penetrate and how long processing should last. Hair with high porosity has open cuticles and holds moisture, so chemicals penetrate faster, meaning you typically need a shorter processing time and a gentler or appropriately weakened perm solution to avoid over-processing. Hair with low porosity has stricter cuticle closure and resists penetration, so it requires a longer processing time and, if needed, adjustments to the solution strength to achieve the same curl without under-processing. Because processing time and the correct strength of the perm solution are both driven by how readily the hair takes in the chemical, porosity determines both. That’s why the statement is true. It’s not about color or curl alone; those outcomes depend on how well the chemical can penetrate, which porosity governs.