Marc with this setup using fp200 etc this again is a water mist system introduced under new EN54 regs. for HMO, nursing homes and hotels. If it ware a sprinkler system, you would require a large reserve water storage tanks, multi pumps and jocky pumps. I would imagine that the system installed is a boxed compressor unit straight off mains water, with pipe work in pvc 20mm and all cabling FP200. A sprinkler system would never be activated by detectors, but a water mist is, as the damage resulting in activation is minimal, and can be cleaned and dry out within hours. unlike the litres of water pumped out by a sprinkler head. Its worth a read up as water mist systems are becoming widely used. They can even be built into kitchen water tapes.