Kansas Barber Practice Exam

When should a patch test be conducted before a chemical service?

1. Immediately before the service

2. 24 to 48 hours prior to the service

3. One week before the service

4. Only if the client has had allergic reactions in the past

The correct answer is: 24 to 48 hours prior to the service

A patch test should be conducted 24 to 48 hours prior to a chemical service to ensure that the client does not have an adverse reaction to the product being used. This timing allows for the assessment of any allergic responses, as reactions could take some time to manifest. Conducting the test too close to the service appointment, such as immediately before or one week prior, may not provide accurate insight into the client's sensitivity to the product. Additionally, performing a patch test only for clients with a history of allergic reactions overlooks the importance of testing all clients, as reactions can occur even in those without prior sensitivities. Thus, the recommended time frame of 24 to 48 hours is crucial for safety and effective service delivery.