A hexane leak occurred above the floating roof of a 30,000-m³ tank 52 m in diameter and 14 m high. Despite application of a foam layer, ignition occurred the following day. The fire was extinguished within 50 min, but a break of the foam film caused by wind (blowing at 20 m/s) led to re-ignition after another 52 min. The second fire required 27 hr to extinguish, once the product had been transferred, necessitating the deployment of 509 rescue workers and the consumption of 200 m³ of emulsifiers.
Total damage was estimated at 30 million Finnish markka. 15,000 of the 22,000 m3 of hexane contained inside the tank burned during the fire.
The hypothesis of ignition triggered by static electricity discharge has received the most support.