Inadequate ventilation probable cause of fire at Sipoo plant
The Finnish Safety and Chemicals Agency (Tukes) has finished its accident investigation of the explosive fire that took place on March 2nd, 2018, at an aerosol filling plant in Sipoo. One person was injured in the accident, and the production facilities and equipment were destroyed. To avoid similar accidents in the future, the investigative team recommends that adequate ventilation is ensured in plants that handle solvents and gases.
The company AT-Tuote Oy produces aerosol products, in which the propellant gas is LPG and the active agents include e.g. solvents. At the moment of the accident a flammable gas or vapor ignited inside the plant.
The investigation concluded that a probable chain of events was that solvent vapors rose close to the ceiling where there was no adequate ventilation. The vapor ignited when a worker opened a vertical lift door.
Adequate ventilation must be ensured, vertical lift door not suitable as an emergency exit
To avoid similar accidents in the future, the investigative team recommends that companies handling explosive gas compounds
- Ensure that the adequacy of ventilation is measured regularly. The air turnover in different areas of the building must be ensured so that gas or solvent vapors cannot accumulate indoors.
- Plants must install enough gas detectors to identify all possible leaks. The alarm of the gas detectors must be detectable inside the building in all the areas where workers might be in danger and near the entrance doors outside the building.
- The storage and handling must be in their own fire compartments. The amount of solvents within the production facilities must be kept as low as possible. Vertical lift doors are not suitable as emergency exits. There must be a door that may be used to exit the premises if the vertical lift door is damaged.
- The building’s pressure relief walls must be designed in a manner that allows pressure to erupt in a safe direction without the risk of collapsing the entire building.
- A good practice is to install the gas alarm as a part of the safety automation system in a way that in case of a gas alarm the automation de-energizes the electrical equipment within the danger area and the pumps that feed chemicals into the process. The pipeline should also include excess flow valves.
Systematicity into practices that affect safety
The workers must be trained to work safely, and they must be told about the plant’s hazards. New and temporary workers must also be trained to safe working methods.
Systematic maintenance must be carried out to all machines, equipment, systems and tools that are related to the handling and storage of hazardous chemicals. Records must be kept of all implemented maintenance activities.
The company must systematically monitor that all demands and recommendations from authorities are carried out. The company must also inform the supervising authority when changes are made that concern the handling and storage of hazardous chemicals.
For further information, please contact
Senior officer Erkki Teräsmaa tel. (+358) 29 5052 386
Project leader Markus Kauppinen tel. (+358) 29 5052 519
email address: [email protected]kes.fi