A leaking liquid hydrogen cryogenic pump shaft during the process of filling a gaseous tube delivery trailer to 2400 psi at a liquid hydrogen transfilling location caused a series of explosions and a fire. After approximately 30 minutes of filling, the operator heard a single loud explosion and then saw flames and ripples from heat generation near the ground in the hydrogen fill area. The operator quickly actuated the emergency alarm system that shut down the cryogenic pump and closed the air-actuated valves on the cryogenic pump supply line. After this shutdown, three smaller explosions were heard as well as the sound of gas releasing from a safety relief valve. The fire department was called to the scene and participated in the final shutdown of the hydrogen system as the fire was view more

An employee at a soap manufacturing plant died in a flash fire outside the facility's hydrogenation building. Responding personnel encountered a fire at the base of the plant's hydrogen storage towers, and they found the victim, who was burned over 90 percent of his body, some 50 feet away.

Officials determined that a pipe connection failed and that hydrogen, pressurized at 1,800 psi, ignited when it was released into the atmosphere, killing the plant operator.

According to reports, the pipe connection failure stemmed from pressures higher than design tolerance, which in turn were the result of over tightening that occurred during routine maintenance replacement. The new bolts were stronger than those they replaced, and the threads of the nuts had been partially view more

Incident Synopsis

A hydrogen compressor had been shut down for repairs and was being put back into service when an explosion occurred, resulting in property damage. The compressor was equipped with interchangeable intake and outlet valves.

Cause

The discharge valve was installed in the intake valve position, causing the cylinder head to blow off and release H2 to the atmosphere. The ignition source was not indicated.

A subcontractor employee was using a band saw to cut a 1" metal pipe when a flash fire occurred on the third floor hydrogen fluoride area. Subcontractor employees were removing all piping associated with the Anhydrous Hydrofluoric Acid (AHF) system. These lines were being removed during plant decontamination and demolition (D&D). The subcontractor employee was attempting to cut a 90-degree elbow located at the highest elevation on the 1" line, but the lowest elevation of the overall piping run. Since hydrogen is lighter than air, it is speculated that a minute amount of hydrogen gas had accumulated in the elbow.

Even though Safe Shutdown personnel had previously opened the system and placed it in a safe configuration, residual hydrogen fluoride could have still view more