What is the purpose of a patch test before a hair color service?

The purpose of a patch test before a hair color service is to check for allergic reactions. This test involves applying a small amount of the hair dye to a discreet area of the skin, usually behind the ear or on the inner elbow, to observe if there are any adverse reactions such as redness, itching, or swelling. Conducting this test is crucial as it helps to ensure the safety of the client; some individuals may have sensitivities or allergies to certain ingredients in hair dyes that could lead to severe reactions if not identified beforehand.

The other options focus on aspects that are not the primary objective of a patch test. The enhancement of color outcome relates to techniques used in the application process rather than how the skin reacts to the product. Determining hair type and assessing moisture levels are important steps in the overall hair care and coloring process, but they do not involve evaluating potential allergic responses to the color agent. Thus, the key objective of the patch test is to ensure that the client can safely use the hair color without risking an allergic reaction.