Our department responded to a vehicle fire with our 2000 E-One 75 ft. Quint. Upon our arrival we found a conversion van with fire showing in the crowded parking lot of a department store. The Captain and firefighter assigned to the apparatus were in the process of stretching the 1 3/4" attack line to the vehicle fire when the apparatus pressure governor ran the engine rpms up abnormally high in an effort to create pressure. The apparatus Engineer could not determine why the apparatus was running the pressure up so high and immediately began measures to reduce the pressure. The pressure was restored to the normal operating pressure for the line that had been pulled. It was then noticed that water was flowing from the LDH discharge on the right side of the apparatus. This was not normal and caused the Battalion Chief on scene observing the company’s operations to investigate the flowing water. During the investigation it was determined that the center of the 5" storz cap on the LDH discharge had blown apart and the discharge was leaking. There were two parts to the cap located approximately twenty feet from the apparatus in the parking lot. The apparatus Engineer attempted, unsuccessfully, to stop the flow of water from the discharge. When units returned to quarters it was determined that the discharge valve was out of adjustment and had been leaking by for an undetermined amount of time. The water resting against the stortz cap had caused corrosion and pitting to the cap. This corrosion along with the pressure being exerted by the pump working at its normal pump discharge pressure caused the center of the cap to fail and fly into the parking lot. When the cap failed the pressure governor on the apparatus increased the engine rpms because it thought the demand for water was being increased. This was the cause of the apparatus engine increasing rpms so quickly. If department personnel had been in the immediate area of the cap pulling the attack line personal injury or death may have occurred.

Lessons Learned 1. Apparatus engineers need to be reminded that if a discharge cap is removed and water leaks from the discharge repairs to the valve need to be made. 2. During apparatus maintenance be sure and check the inside of caps and turndowns for pitting and corrosion. If they show signs of this they need to be replaced which is what NFPA 1962 recommends. 3. The cap needs to be tested according to NFPA 1962 once it is cleaned and lubricated or needs to be replaced.