A kit comprising a composition comprising one or more oil or water soluble ultraviolet sunscreen agents and a fluorescent chromophore, wherein the fluorescent chromophore is oil soluble and has a wavelength of excitation greater than about 400 nm and a device for determining the presence of the composition on a surface, which device comprises a light emitter, a light detector, an electronic evaluation system to determine the level of fluorescence of the fluorescent chromophore, and a display system.
