Texas Cosmetology Operator Written ExamHair Care ServicesMedium

A client with fine, delicate hair desires a permanent wave that will create soft, natural-looking curls with minimal damage. Which type of perm would be most suitable?

  1. AAlkaline perm (cold wave)
  2. BExothermic perm
  3. CThioglycolate-free perm
  4. DTrue acid perm
Show answer & explanation

Correct answer: D. True acid perm

True acid perms are ideal for fine, delicate, or fragile hair because they have a lower pH (4.5-7.0) and process more gently, resulting in softer, more natural-looking curls with less potential for damage compared to alkaline perms.

Why the other options are wrong

  • A. Alkaline perms are strong and best for resistant hair, too harsh for delicate hair.
  • B. Exothermic perms generate their own heat and can be strong, not ideal for delicate hair.
  • C. Thioglycolate-free perms (often called 'thio-free' or 'cysteinamine' perms) vary in strength and are not inherently the gentlest option.

True Acid Perms

Permanent waves with a low pH (4.5-7.0) that process more slowly and gently than alkaline perms, making them suitable for delicate, fine, and color-treated hair to create soft, natural curls.

  • Require heat to process (hood dryer).
  • Produce softer, looser curls.
  • Minimal damage due to lower pH.

Memory trick: Acid perms are for gentle curls, not aggressive ones.

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