Abstract: ON APRIL 4 1987, EMPLOYEES #1-7 WERE CHANGING AN AIR/OIL SEPERATOR TANK WHICH HAD A LEAKY SEAM. THE OWNER, SAMUEL CROSS, HAD REMOVED ALL AMMONIA FROM THE LEAKY TANK AND CLOSED THE BUTTERFLY VALVES FEEDING THE TANK. AS THE EMPLOYEES WERE INSTALLING THE NEW TANK, A JAMESBURY VALVE OPENED, SPRAYING THE EMPLOYEES WITH AMMONIA. THIS VALVE WAS ON A 6 INCH LINE. THE VALVE HANDLE HAD TEETH TO HOLD IT CLOSED BUT THERE WAS NO WAY TO LOCK IT OUT. THE VALVE DESIGN ALLOWED ACCIDENTAL OPENING. THE TANK WAS 30 INCHES BY 6 FEET AND WAS MOVED BY A CRANE. EMPLOYEES #1-7 SUFFERED AMMONIA BURNS AND RESPIRATORY PROBLEMS. EMPLOYEE TRAINING PRIOR TO THE ACCIDENT HELPED SAVE THEIR LIVES.