NIC Barber Written (Theory) ExamHair Care ServicesHard
A barber is evaluating a client's hair prior to a permanent waving service. The client's hair has been previously bleached and feels rough with a high porosity. Which type of permanent waving solution would be most appropriate for this hair type?
- ALow pH alkaline wave
- BExothermic wave
- CAlkaline (cold) wave
- DTrue acid wave
Show answer & explanationAnswer & explanation
Correct answer: D. True acid wave
Bleached, porous hair is highly susceptible to damage. A true acid wave, with its lower pH (4.5-7.0) and slower processing time, causes minimal swelling and damage, making it the safest choice for such fragile hair.
Why the other options are wrong
- A. Low pH alkaline waves, while less alkaline than traditional alkaline waves, are still too strong for severely bleached and porous hair compared to a true acid wave.
- B. Exothermic waves are self-heating and generally alkaline, making them unsuitable for damaged hair due to their aggressive action.
- C. Alkaline waves have a high pH (9.0-9.6) and are too strong for bleached, porous hair, causing excessive swelling and damage.
True Acid Permanent Wave
A type of permanent waving solution that has a pH between 4.5 and 7.0, typically requiring an outside heat source to process. It causes minimal swelling of the hair cuticle, making it suitable for delicate, porous, or previously damaged hair.
- Main active ingredient is glyceryl monothioglycolate (GMTG).
- Processes slower than alkaline waves.
- Results in softer, looser curls and less damage.
- Not recommended for use on extremely healthy, resistant hair.
Memory trick: Acid waves are kinder to hair.