EE WAS SERVICING A WAGNER SHUTTLE CAR AND WAS ATTEMPTING TO FILL THE SCRUBBER MAKE-UP TANK WITH WATER. THE FILL HOLE ON THE MAKE UP TANK IS LOCATED SO EE HAD TO REACH ABOVE HIS HEAD TO KEEP TH E HOSE IN THE TANK. EE OPENED THE BALL VALVE ON 3/4"" WATER HOSE ABOUT HALF-WAY AND THE BOOSTER PUMP CAME ON, INCREASING THE PRESSURE IN THE TANK . THE END OF THE WATER HOSE CAME OUT OF THE TA