The incident occurred in a facility chrome-plating metals. At the time of the event, a metal roller was being chrome-plated. A short circuit occurred due to a defective contacting (contact rails) on the rectifier. This short circuit caused a spark to reach the surface of the electrolyte bath, and the spark ignited the hydrogen produced during chrome plating, causing an explosion.Various windows within the company were destroyed, but nobosy was injured.

A leak occurred at a of a liquid withdrawal valve of a liquid hydrogen storage tank. The hydrogen escaped at the flange between the valve body and the upper part of the valve (flange with tongue and groove). 40 kg of hydrogen were lost.The accidental release was due to the use of bolts different from those prescribed. By using the wrong ones (old bolts), the bolt material was able to flow at the specified tighteningtorque. This meant that there was insufficient tightening torque, which led to a leak.

The event occurred at the hydrogenation unit of a pharamceutical company. 145 kg of hydrogen were released the atmosphere at the gas circulation pump, due to a maintenance error . A specialist company (third-party company), had replaced the cylinder head of pump, but during assembly they did not re-isntalled the prescribed temperature sleeve for the thermometer (the temperature sleeve is the pressure-bearing element).

This event occurred when a hydrogen-carrying trailer was supplying hydrogen to a chemical plant. Instead of filling the hydrogen stationary storage, large quantities of hydrogen were transferred from the trailer into the compressed air plant network. The explosive atmosphere ignited in a compressed air consumer (a solid silo which was not containing hazardous materials).

On a highway, a truck loaded with 400 gas cylinders crashed at night for an undetermined cause against a concrete wall and overturned. It slipped 150 m, before several 200 litre cylinders of hydrogen caught fire and set the truck on fire as well. The police stated that it was a large fire with detonations. The 400 gas cylinders were connected together and many of the cylinders had fallen out of their racks. In order to reduce the danger of further explosions, the fire-brigade cooled the gas cylinders with water for two hours. The highway remained closed for eight hours.

A lightning strike caused a voltage drop on the power supply of a chlorine-alkali plant using the mercury process.The emergency electrical system was activated, though restoring the external supply voltage in less than 200 ms rendered the entire system inconsistent; some units were operating normally, but all units connected to the emergency devices (including the mercury pump) remained idle. An explosive mix of 500 kg of chlorine and an unknown amount of hydrogen accumulated inside the low-pressure chlorine treatment circuit.

The incident consisted of a leakage of potassium hydroxide solution (KOH) from an alkaline electrolyzer in a renewable hydrogen production plant. One webpage news reported that smoke formation triggered the fire alarm system. According to the manufacturer, the equipment shut down and automatically went into safety mode in accordance with the integrated safety system.Nobody was injured in the event and there was no damage on the environment.

This incident occurred in a unit processing vegetable oils and fats. A fire-brigade from the involved town was at the scene in a few minutes and was assisted by the Fire Department of a bigger city. Approximately one hour later the fire was extinguished. An employee of a contractor was injured when he fell from a scaffold, and two truck drivers were examined as outpatients. The results of the internal investigation is not publicly available.

The safety cabinet with compressed hydrogen was located in a laboratory and used to supply hydrogen to an experimental facility. The safety cabinet was equipped with exhaust extraction. Due to a leak, technical assistance had been requested from the fire department. The head of laboratory shut off the electrical supply to the laboratory. Measurements showed that there was no potentially explosive atmosphere in the laboratory room.

The event occurred at manhole cover of a of a pilot plant reactor where hydrogenation had been performed in a hydrochloric aqueous solution. The reactor had been flushed three times with nitrogen (i.e. nitrogen injecting at 3.2 bars and then relieving). An employee opened the manhole cover of the reactor to take a sample of the reagent. . After opening it, a minor detonation occurred.According to the DECHEMA database, the investigations found out these following causes:1.