Abstract: A cleaning inspection kit inclusive of various compositions of water-soluble invisible fluorescent ink and various applicators therefor which are suited for a number of different surfaces, and a hand-held ultra-violet light. The appropriate applicator is used to mark an area with invisible compound prior to cleaning. After the area has been cleaned an inspection is made with the ultra violet light to expose the original area and to determine whether remnants of the original mark are still there. If so, the area could not have been properly cleaned. However, if the original mark is gone then the area was cleaned. The system allows management to inspect the quality of cleaning and maintenance services. The kit is simple to use as the inks are applied by convenient pen, powder or spray applicators, and a portable ultra-violet light is provided for fluorescing the inks. The method is non-destructive as all of the ink compositions wash away upon normal cleaning.