During curling test, the wave dimension should match the diameter of the perm rod.

During curling test, the wave dimension should match the diameter of the perm rod.

• A. The diameter of the perm rod
• B. The width of end papers
• C. The length of hair
• D. The rod color

Answer: (A)

Wave dimension is determined by the diameter of the perm rod. The size of the curl you create—its wave dimension—depends on how thick the rod is, so the test should reflect that relationship by using a rod whose diameter defines the curl size you’re evaluating. End papers’ width affects wrap and protection, not the curl size. Hair length can influence processing and evenness, but it doesn’t set the wave dimension. Rod color adds no functional effect on curl size.

Wave dimension is determined by the diameter of the perm rod. The size of the curl you create—its wave dimension—depends on how thick the rod is, so the test should reflect that relationship by using a rod whose diameter defines the curl size you’re evaluating. End papers’ width affects wrap and protection, not the curl size. Hair length can influence processing and evenness, but it doesn’t set the wave dimension. Rod color adds no functional effect on curl size.