The fire occurred on the tube plate gaskets of 3 of the 4 exchangers loaded with catalytic reforming effluent. The fuel (500C and p=30 bar) was a mixture of 30% hydrocarbons and 70% hydrogen. After depressurisation of the unit and nitrogen flushing (some problems to access the valves), the exchangers being cooled (overall flow 600 m/h on 3 units), the fire was controlled until extinction by nitrogen injection. The accident was apparently due to incorrect tightening of the threaded rods; only 1/5 were correctly tightened on one of the heat exchangers involved.

A violent explosion occurred in a refinery's crude oil hydrodesulfurization unit. The unit's alarm is immediately triggered in the control room, the operator activates the internal emergency plan. The site's firefighting team went to the site and brought a fire under control. The external fire fighters service did not need to intervene. The accident caused two fatalities and to five injuries among the workers.

During a patrol, an operator detects a hydrogen leak in a refinery on a footbridge 30 meters high. The origin of the leak is identified 4 days later on a pipe under insulation. The operator proceeds to remove the insulation (under SCBA). The leak is located at the level of a reinforcing saddle. The installation is shut down and put under nitrogen. Thickness measurements and radiographic checks are used to characterise the nature of the crack defect. A leak sealing system (SOFM) is put in place while awaiting the removal of the pipework for assessment during the next shutdown.

In a fertilizer manufacturing plant, during his inspection round, an operator detected a hydrogen leak at a flange of an exchanger located between the conversion and decarbonisation stages of the ammonia processing unit. He alerted the control room. A steam hose is installed blowing towards the flange to dilute the leak. Explosive gas measurements are taken twice per shift to ensure that the consequences of the leak are under control. The area is placed under surveillance. A few days later, 2 vapour rings were placed around the flange.

Excavation work was performed nearby a buried pipeline of gaseous hydrogen. The excavation machine hit the pipeline causing an under-expanded jet fire. No injuries. The excavation machine was burnt during the accident.Additional investigations are in progress to understand why the third party company was not informed or has not transfer the information to the workers of the presence of the hydrogen pipeline.

The accident took place when replacing a pallet of empty hydrogen cylinders with a new full one. The pallet in service (almost empty) was not disconnected from the gas supply line. When the operator in charge of handling (fork lift) begun to remove the pallet in service from its position, he teared off the hose connecting it to the pressure relief system. The pressurised hydrogen in the pipes and in the pallet escaped and ignited. The intervention of the teams from the plant and external emergency services extinguished the fire in 1h45.

The explosion occurred at a hydrogen fuel plant mainly serving hydrogen forklift fleets. The explosion damaged several nearby homes and could be felt nearly 10 miles away.Police and firefighters responded and not injury was reported. Several houses in the neighbourhood experienced glass breaking. According to a statement of the company, "...there was no detonation of any on-site storage tanks and no workers were injured."

In a chemical plant (SEVESO), corrosion on the water side of a cooling exchanger caused water to enter the sulfuric acid and attack the steel in the tank. This reaction produced hydrogen that accumulated in the dome of the tank and caused the explosion.The explosion causes the cover of a 99.2% sulfuric acid tank to open partially. The tank was filled to 300 t of its total 1500 t capacity. The cover opened along the circumference of the tank at the dome / shell fitting. The POI (internal emergency plan) was started.

An empty 100-m reservoir of sulfuric acid (H2SO4) exploded at 9:15 am at a chemical site. Installed directly above its retention basin at a height of several metres, this reservoir was projected and fell nearby, toppling the scaffolding set up for reservoir maintenance and causing 3 workers (2 subcontracted personnel) to fall. Two of the three were seriously hurt. The internal emergency plan was activated, bringing both internal and external responders to the site. The injured were taken to hospital. The operator notified the Prefecture, local city halls and the general public.

In a paper plant, an explosion occurs in a paper pulp tank while 2 workers were carrying out pipes cutting with a grinder on the roof of the tank. Detailed analysis of the event was performed by two independent experts.