Abstract: A device for monitoring UV radiation received by the skin comprises a housing. Adhesive on a face of the housing secures the device to the skin. A patch of irreversible UV sensitive material which changes color on being subjected to UV radiation is applied to an inner surface of the housing and receives UV radiation reflected from the skin. The color of the UV sensitive patch is compared with reference colors on the housing for determining the quantity of UV radiation to which the skin has been subjected.