At 9:35 a.m., a fire broke out in the electrical room of plant where plastic technical parts are manufactured. The alarm went off. The remote guarding company did not pass on this information because the site’s fire detection system was being tested and the remote security officer had been told not to call during these tests. At around 9:50 a.m., black smoke began coming out of the room’s ventilation system, alerting staff. The site’s emergency response teams fought the fire with five CO2 extinguishers, but were unsuccessful. They were finally able to extinguish the fire with two powder extinguishers before the firefighters arrived at 10:10 a.m. The firefighters left 20 minutes later. The presses were put back in service at around 5:00 p.m. The high-voltage line passing 50 cm above the electrical cabinet was not damaged by the fire.

The electrical room, blackened by the smoke, was cleaned at a cost of €1400. Seven injection presses were shut off for 16 hours and the assembly lines were down for eight hours.

The fire was caused by defective capacitor banks. The banks’ manufacturer had informed users about the technical defects involving certain serial numbers, but this information was not sent to the site. Under certain environmental conditions, these banks may age prematurely and start a fire. A similar case occurred at another company that owned capacitors with corresponding serial numbers. The contractor who installed the capacitors at the site notified another plant that owned capacitors with the same serial numbers.

The operator took the following immediate steps:

• the room’s two fire detection sensors that had tripped were replaced;
• the burnt cabinet was placed in another room to be assessed;
• all the site’s capacitor banks were shut off and bypassed.

The operator subsequently plans to:

• replace the damaged capacitor bank cabinet;
• add checking the capacitor bank cabinets’ cooling fan to the internal checklist;
• install a smoke detector in the new cabinet with control of the circuit breaker;
• calculate the losses from the fire so that they can be rebilled.