This method is used as a technique to indicate the skin compatibility of any test product that come into contact with the human skin. The test products are applied to the volar forearms of the volunteer via an occlusive patch. The skin is assessed at T24Hrs, T48Hrs and T72Hrs after application and observations made at each time interval. Patch testing is generally regarded as the first step and minimum test requirement for any newly developed cosmetic test product. A dermatologist endorsement, upon favourable completed test results, can be requested. Irritancy patch testing is performed according to the international Cosmetics Europe guideline (Product Test Guidelines for the Assessment of Human Skin Compatibility – COLIPA GUIDELINES 1997).