Abstract: AN ELECTRICIAN WAS USING A STEEL TAPE TO FISH AN EQUIPMENT GROUNDING CONDUCTOR THROUGH AN UNDERGROUND CONDUIT. THE 200-FOOT STEEL TAPE WAS BEING USED IN A 400-AMPERE, 480-VOLT, THREE-PHASE FOP PANELBOARD (MODEL NUMBER M3A, SERIES C). THE PANELBOARD WAS WITHIN A 1200-AMPERE, 3-PHASE, 4-WIRE, 480/277-VOLT COMPARTMENT. THE ACCESS PANEL OPENING FOR THE PANELBOARD WAS 23 INCHES WIDE AND 9.5 INCHES HIGH AND WAS ABOUT 3.5 INCHES ABOVE THE FLOOR. AN ENERGIZED BUSBAR WAS LOCATED INSIDE THE PANELBOARD, ABOUT 4 INCHES ABOVE THE OPENING. THE ELECTRICIAN WAS FEEDING THE TAPE THROUGH A 4-INCH-DIAMETER PVC CONDUIT THAT WAS ENCASED IN CONCRETE AND THAT HAD THREE, 0.75-INCH-DIAMETER CABLES IN IT. THE EMPLOYEE WAS LYING ON HIS RIGHT SIDE FEEDING THE TAPE THROUGH THE CONDUIT, AND THE TAPE HUNG UP. THE STEEL TAPE CONTACTED THE 480-VOLT BUSBAR, AND THE RESULTANT ELECTRIC ARC, EXPLOSION, AND FIRE CAUSED FIRST AND SECOND DEGREE BURNS ON THE EMPLOYEE'S LEFT ARM (FROM HIS FINGERS TO THE MIDDLE OF HIS UPPER ARM), ON THE RIGHT SIDE OF HIS NECK, AND ON THE UPPER PORTION OF HIS RIGHT ARM.