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A fuel cell forklift operator stated that he observed a "ball of fire" coming from the left side of the forklift that seemed to flash and extinguish. Investigators found no external signs of a fire, but the forklift would not start. The fuel cell power pack access panel was removed to enable investigators to search for any internal signs of a fire. Some areas inside the fuel cell stack appeared to have experienced an electrical arc or some type of overheating. All connections were verified to be tight and secure. The internal fuel cell stack circuit board cover was then removed, and the circuit card on top of the stack also showed signs of overheating. After the fuel cell stack circuit board was removed, a broken drill bit was discovered on top of the fuel cell stack plates. view more

The evaporator pad in a fuel cell power unit installed in a hydrogen-powered forklift caught fire during operation. The evaporator pad is used for wicking the product water created by the fuel cell. The operator dismounted the forklift, observed flames coming from the fuel cell unit, and called for help. The facility fire brigade used a fire extinguisher to put out the fire. The upper left corner of the fuel cell evaporator pad was burned entirely; the plastic bracket that holds the evaporator pad in place was distorted; there was some discoloration of the radiator. No injuries were sustained by the operator and no damage was sustained by the forklift.

The fuel cell unit continued to run during the incident, as did the onboard data acquisition device. Hydrogen concentrations view more

The incident occurred in the catalytic hydrotreatment plant of an oil refinery. The plant, which began operations in September 1997, has a capacity of 1650 tons/day of light fuel oil and 1450 tons/day of heavy fuel oil. The plant was designed to desulfurize the light and heavy fuel oil fractions produced in the refinery by treating them with high-pressure hydrogen over a catalyst to remove sulfur (producing hydrogen sulfide as a byproduct). The plant has two heating/reaction/fractionating sections to treat the two fuel oil fractions, but a single gas purification and compression section for the recycled hydrogen gas.

The heavy fuel oil reactor feedstock from the vacuum distillation plant is sent to the heavy fuel oil treatment section through three pipelines equipped with flow view more


During an external review of the facility safety basis document, it was identified that the accident analysis for the pool cell area hydrogen explosion did not account for release of stored hydrogen from the pool cell water as the temperature of the water increases. The analysis only accounted for the hydrogen generated by radiolysis. A loss of pool cell cooling occurring concurrently with a loss of ventilation would result in a higher concentration of hydrogen in the pool cell area than calculated in the safety basis. The safety basis document is being revised to account for the increase in hydrogen concentration.

First responders were dispatched to the waterfront area to investigate a possible explosion on an 85-foot dinner cruise boat that was moored there. Upon arrival, the incident commander noted that nothing out of the ordinary was visible on the exterior of the boat. A crew was sent to the interior of the boat to investigate. The boat was powered by diesel engines and there were no compressed gas cylinders on board.

After further investigation, it became apparent that the explosion had come from the battery compartment in the hull of the boat. The responders concluded that one of the batteries had been giving off hydrogen gas, which gradually built up inside the compartment. Since the compartment was not vented, the gas had nowhere to go. It found an ignition source (possibly a view more