What must barbers do before applying any chemical treatments?

Performing a patch test for allergies is a crucial step before applying any chemical treatments. This procedure involves applying a small amount of the chemical product to a discreet area of the client's skin, usually behind the ear or on the inside of the arm, to check for any adverse reactions. It is essential as some clients may have sensitivities or allergies that could result in irritation, discomfort, or more severe reactions if the product is applied directly to the hair or scalp without prior testing. By conducting this test, barbers ensure the safety of the client and minimize the risk of allergic reactions, which could lead to significant discomfort or even medical emergencies. This practice emphasizes the importance of client safety and demonstrates a barber's professionalism and commitment to their clients' well-being.