A trained operator was blending water, sand, anhydrite, lime, cement, pulverized fly ash, and powdered aluminum in a mixing chamber to produce material for making concrete building blocks. In the blending process, sand and water are mixed to form a slurry, and then the powders are dispensed automatically into the mix by a computer-controlled system. Finally, a slurry of glycol-coated aluminum powder is added in the last few seconds before the mix is discharged into a car, and then molds are filled from the car. Adding aluminum to the mixture results in a small amount of hydrogen gas evolution, which disperses from the car into the surrounding ventilated area and out through roof vents. In addition to being an ingredient of the mix, water also helps to keep the mixture cool.

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A hydrogen leak at the flange of a 6-inch synthesis turbocharger valve in an ammonia production plant ignited and exploded. Hydrogen detectors and the fire alarm alerted the control room, which immediately shut down the plant, and the fire was then extinguished rapidly. There were no injuries caused by the accident, since the operator heard a wheezing sound and was able to run away just before the explosion occurred. The leaking gas was composed of 70% hydrogen at a flow rate of 15,000 cubic meters per hour. Property damages in the turbocharger included electrical cabling, melted siding, and heavily damaged pipes. The ammonia plant was shut down for more than a month.Five days before the incident, a problem with the CO2 absorber column led operators to open the vent downstream of the view more

A hydrogen leak originating from a tank within a high-pressure storage unit serving a hydrogen vehicle fueling station resulted in fire and explosion. Emergency responders were on scene within 7 minutes and contained the fire within 3hours. No damage was reported to the separate forecourt H2 dispenser or to other major station components within the station backcourt compound. No personnel injuries resulted directly from the fire and explosion -a nearby vehicle airbag triggered due to the explosion pressure, with minor injuries to the vehicle occupants. Immediately, until root cause was determined, all potentially affected H2 stations were idled.

The root cause of the incident was subsequently identified as an assembly error of a specific plug in a hydrogen tank in the high- view more

A hydrogen leak originating from a tank within a high-pressure storage unit serving a hydrogen vehicle fueling station resulted in fire and explosion. Emergency responders were on scene within 7 minutes and contained the fire within 3 hours. No damage was reported to the separate forecourt H2 dispenser or to other major station components within the station backcourt compound. No personnel injuries resulted directly from the fire and explosion -a nearby vehicle airbag triggered due to the explosion pressure, with minor injuries to the vehicle occupants. Immediately, until root cause was determined, all potentially affected H2 stations were idled.

The root cause of the incident was subsequently identified as an assembly error of a specific plug in a hydrogen tank in the high- view more