CONTRACTOR HAD TAKEN OUT A 6'X6"" SECTION OF A CONCRETE FLOOR IN 2ND SUBSTATION. HE WENT TO THE FLOOR BELOW TO VIEW. WHEN HE LOOKED UP, A CLEANING SOLVENT ENTERED HIS EYE. NOTE: HE HAD HIS SAFE TY GLASSES ON, HOWEVER HE HAD TAKEN THEN OFF MOMENTARILY TO CLEAN WHEN HE LOOKED UP.