The site, classified as SEVESO II (European legislation on major hazards), is entirely devoted to assembly work on pyrotechnics. The process is divided up between some thirty small buildings, which is normal for this type of industry. Certain areas are reserved for the pyrotechnical machines. The land is entirely fenced in and isolated from any other businesses. Site operations mainly take place from 7:30 a.m. to 4 p.m., Monday-Friday. Nevertheless, two security guards are present 24/7 at the guard station where all of the fire and intruder alarms go off.
On a Wednesday, at around 5 a.m., an alarm goes off at the guard station, stemming from a sprinkler system in a building devoted to pyrotechnical work, approximately 2,000 m2 in surface area. At that very moment, one of the security guards is doing monitoring rounds on the site. Alerted by his colleague at the guard station, he immediately goes to the location in question. He there finds that a utility room is completely filled with smoke and that a sprinkler head has been triggered. The sprinkler alarm triggered automatic shutdown of the utility installations (4 air handling units) and simultaneously closed the fire dampers in the air ducts.
The 64 m2 utility room had a 2-hours fire cutoff rating. The pass-throughs for cables, ducting and other services were completely sealed off using fire cutoff materials with specifications similar to those of the walls. The equipment contained in the room was as follows: air handling units (HVAC), electric distribution cabinets, inverters, power cabinets, humidifiers, building management systems (BMS), etc.
