NIC Barber Written (Theory) ExamHair Care ServicesHard
A barber is preparing to perform a permanent waving service on a client who has previously colored hair. Which type of permanent wave solution would be most suitable to minimize damage and ensure a successful result for this client?
- AAmmonia-free thiol waves
- BExothermic waves
- CTrue acid waves
- DAlkaline (cold) waves
Show answer & explanationAnswer & explanation
Correct answer: C. True acid waves
True acid waves (pH 4.5-7.0) are the gentlest type of permanent wave solution, making them ideal for delicate, color-treated, or damaged hair. They process slowly and require external heat, minimizing the risk of over-processing and damage.
Why the other options are wrong
- A. Ammonia-free thiol waves are less alkaline than traditional alkaline waves but still generally stronger than true acid waves, and may not be the *most* suitable for highly compromised hair.
- B. Exothermic waves (pH 9.0-9.6) are also highly alkaline and produce their own heat, making them unsuitable for fragile hair.
- D. Alkaline waves (pH 9.0-9.6) are strong and can be too harsh for previously colored hair.
True Acid Permanent Waves
A type of permanent wave solution with a low pH (4.5-7.0) that is ideal for delicate, color-treated, or damaged hair. It processes slowly and requires the application of external heat.
- Main active ingredient is glyceryl monothioglycolate.
- Requires external heat (hood dryer) to process.
- Produces soft, natural-looking curls.
- Minimizes swelling of the hair, reducing damage.
Memory trick: Perm types: 'Acid is Gentle and needs Heat, Alkaline is Strong and Cold, Exothermic is Strong and Hot.'