Which perm type uses heat to speed processing?

• A. Exothermic perm
• B. Alkaline perm
• C. Neutral perm
• D. Acid perm

Answer: (A)

Exothermic perms are designed to release heat during processing, and that heat speeds up the chemical reactions inside the hair. As the reducing agent breaks disulfide bonds and then reforms them in the new curl pattern, the heat produced accelerates both the chemical action and the diffusion of these agents into the hair. That faster processing time is a hallmark of this type, and you’ll often feel warmth on the hair as it works.

Other perm types rely on the chemical environment rather than generated heat. Alkaline (cold-wave) perms use a high pH to soften bonds without depending on heat to drive the reaction, so processing is slower and not heat-activated. Neutral perms are milder and work mainly through time and pH balance, not heat production. Acid perms use an acidic medium and a controlled processing time, with heat not being the defining feature. So, the one that inherently uses heat to speed processing is the exothermic perm.