A pressure safety disc on a liquid oxygen storage system consisting of four horizontal cylindrical tanks began leaking at a glass plant at around 8:45 p.m. The plant’s firefighters set up a cordon. They used water hoses to abate the cloud of gas, but experienced difficulties opening the valves because they were frozen. The operator implemented the site’s internal emergency plan. The site employees as well as 23 people from six neighbouring dwellings were evacuated. At around 1:30 a.m., the leak was stopped by a technician of the company that owns the tanks. The pressure safety disc was replaced.

After the event, the inspection authorities for classified facilities found the following irregularities:

• 4.5 hours had elapsed between the leak and the time it was taken in charge by the contractor’s technician;
• a lack of communication between the contractor and the site’s operator;
• ageing or damage to the pressure safety discs;
• a leak on a supply valve;
• non-compliance with regulations on the redundancy of overpressure safety devices, particularly regarding the position of the safety valve;
• non-compliance regarding the regulations on controlling and tracking safety devices.

They required the operator to draw, along with his contractor, an action plan specifying the roles and responsibilities of one another, response-times instruction, and checklists of questions to ask to the contractor in case of emergency situations and during unloading operations. The internal emergency plan must also take into account feedback from the event as well as employee training.

Lastly, the operator has also been required to ensure that it remains accountable for the proper management of other subcontracted hazardous activities at its site.