A monitoring device (201, 102, 104) which is attached to or integrated within a product container body, lid, cap or spray unit (200) with a built in sensing indictor alarm circuit that indicates and gives a audio indication that the effectiveness of a product has been reduced below a predetermined level. The product could be a sun protection material in the form of a liquid, cream or lotion or other materials in the forms of medicines, food, toiletries etc. The device may alert the user when exposed to ultraviolet radiation for a specified period, that they need to re-apply the sunscreen material, thus reducing the risks associated with over exposure to UV radiation. The monitoring device may also indicate to the user that the product is at or has gone beyond its expiration date and helps prevent use of the product before it becomes hazardous.
