Heavy rains (more than 600 mm in 1 day) had flood a factory manufacturing calcium core electrical conductors. The power supply was cut off. The water came into contact with the calcium stored in 150 kg containers, producing hydrogen (7.5 kg per container). The heat of reaction ignited the gas. The fire was extinguished with sand.

Hydrogen was accidentally produced inside the sealed container containing a used battery. The gas, along 6 days deformed the container. Firefighters equipped with breathing apparatus open the container remotely triggering a considerable explosion.

Release from a compressed storage of an optics component plant The leak was observed on the hydrogen storage consisting of 19 racks of 16 cylinders each. Rescue teams set up a security perimeter and a specialized company inspected the leak.The activity of the establishment were interrupted during the night and resumed the next morning.

Electric spark ignited hydrogen in a captive advertising balloon.

Static electricity ignited hydrogen in a rising advertising balloon.

The explosion occurred during repair work on a boiler. A technician had previously descaled the device using hydrochloric acid, after which he performed the neutralisation step with soda and drained the passivated acid. The significant scaling on the boiler required a second acid injection, followed by welding work, but this time the rest of the acid had not been drained from the boiler. Hydrogen emitted by a metal + acid reaction was the cause of this accident. An employee wound up in hospital in a coma.

Leakage of a mixture of hydrogen, nitrogen, citric, hydrofluoric and hydrogen sulfide occurs during ventilation shutdown on high temperature PVC furnaces. The accident follows an electrical outage related to the failure of a general circuit breaker during the switchover by the electricity providers from the emergency power supply to the main power supply.

Hydrogen leak occurred during a delivery of hydrogen at an automotive supplier. Rescue deployed a curtain of water and evacuated 82 employees from several companies within a radius of 50 m. The hydrogen installation was then purged. The intervention ended at 4 hours later. The accident was caused by a rupture of a connection element (lyre) between the hydrogen bottle in the delivery truck and the receiving tank.

In the acid treatment room of a Seveso low-threshold hazardous waste treatment centre, an explosion occurred on a 250 m concrete tank containing acid sludge being neutralized. The explosion occurred when the employee left the room and cut off the lighting of the building. The building was evacuated. The employee, severely burned, was transported to the hospital. Firefighters intervened. The concentration close to tank ceiling was 80% of the LFL. The operator filled the tank with water. The next day, the concentration was less than 10% of the LFL.The upper hatch of the tank was torn off.

The event occurred at the factory producing multilayer circuit boards by a multistep dip operation. An employee inadvertently mixed 55 gal of 50 percent hydrogen peroxide into 110 gal of 30 percent formaldehyde. This resulted in a carbon monoxide and hydrogen release. The facility was evacuated and the local fire department and ambulance responded. 14 workers, out of whom three were from temporary employment agencies, were treated for inhalation and released.The employee did not look carefully at the label on the hydrogen peroxide drum.