What is the Acid Mantle and why should I care about the pH of my skin? There is a thin, protective layer, or barrier, on the surface of our skin, referred to as the acid mantle. The acid mantle is responsible for keeping in lipids, moisture and other desirables while blocking out germs, pollution, toxins and bacteria. As you can imagine, it’s important to keep your acid mantle healthy and intact. The pH level of the skin refers to how acidic or alkaline it is. On a scale of