The high-expansion foam fire-suppression system of a warehouse unexpectedly went off at around 11:00 p.m. The system shut off at around midnight after an overheated diesel pump (which gave off smoke) was flooded. The operator restarted the facilities at around 2.30 a.m. and ensured that fire protection systems were effective (implementation of compensatory measures).

A technician was sickened by the smoke from the overheating pump after the fire suppression system shut off. The incident caused an estimated €0.1 million in material damage (stored products, flooded electrical systems, overheating of certain types of equipment in the foam room) and €0.25 million in operating losses (cleaning and closure of the warehouse). As for the environmental impact, an estimated at 200 m³ of firewater was discharged and confined in a pond and then treated.

The incident was caused by a contractor who mistakenly closed a valve on the newly installed system. This caused the pressure in the network to progressively drop and activated the fire-suppression system.

After the event, the operator put forward the following actions to the authorities:

• installing a flame detector to confirm the presence of fire (considered optional by the installer);
• installing a device to warn in the event of a drop in pressure (deemed unnecessary by the installer);
• providing the employees with refresher training with clear indications about the positioning of valves and the development of written instructions;
• better supervision of the restarting of the system;
• linking the control of the valve in question to the warning system to prevent the fire-suppression system from being restarted if the valve is closed;
• setting up equipment so that individuals can go through the foam without exposing themselves to injury (searches for victims, lifting of doubts);
• looking into a means for automatically shutting off the systems when the water tank is empty so as to avoid the risk of overheating the pumps and creating a secondary fire;
• removing the fuel tanks (1 m³) from the foam room to limit the risks in case of fire.