Abstract: AN EMPLOYEE CLOSED A SWITCH TO RUN A POSITIONER FOR WELDING OPERATIONS. THE SWITCH CONTROLLED ELECTRIC POWER TO A NEARBY RECEPTACLE OUTLET USED TO CONNECT A WELDER OR THE POSITIONER. AS THE EMPLOYEE WAS OPERATING ITS HANDLE, IT BROKE OFF AS SOON AS THE SWITCH WAS PARTIALLY CLOSED. AFTER HE DID THIS, THE POSITIONER WAS WORKING; HOWEVER, THE EMPLOYEE RETURNED TO THE FRONT OF THE SWITCH TO SEE WHY THE HANDLE BROKE. APPARENTLY, THE COVER ON THE SWITCH, WHICH WAS A TYPE THAT HAS SLIDING CONTACTS, WAS NOT PROPERLY SNAPPED INTO PLACE; AND, SINCE THE TURNING MECHANISM WOULD BE OUT OF ALIGNMENT, THE SWITCH WOULD NOT CLOSE FULLY. IN THE MEANTIME, THE COVER OF THE SWITCH SLID DOWN AND CONTACTED THE HALF-CLOSED BLADES ON THE THREE POLES OF THE SWITCH (THE THREE POINTS OF CONTACT WERE QUITE EVIDENT ON THE SWITCH COVER). THE METAL COVER'S CONTACTING THE ENERGIZED PARTS OF THE SWITCH CAUSED AN ELECTRICAL FAULT. THE ENSUING ELECTRIC ARC BURNED THE EMPLOYEE, WHO WAS STANDING IN FRONT OF THE SWITCH. THE EMPLOYEE WAS HOSPITALIZED FOR HIS INJURY. THE CAUSE OF THE LOOSENESS OF THE COVER COULD NOT BE DETERMINED.