What is the purpose of a patch test?

The purpose of a patch test is to see if a client has an allergy, which is critical in the context of eyelash extensions. This process involves applying a small amount of the adhesive or other products to the client's skin, typically behind the ear or on the inner arm, to observe if any allergic reaction occurs.

Identifying allergies before applying extensions is essential for client safety, as allergic reactions can lead to discomfort, swelling, and other adverse effects that might not only affect the client's experience but could also lead to further health complications. It’s vital for beauticians to ensure that the products used are compatible with the client's skin before proceeding with a full application.

The other options, while they may involve aspects of eyelash extension application, do not serve the specific purpose of ensuring safety in terms of allergic reactions.