Wet system features: ① simple structure, Shandong fm certified gas fire extinguishing products, equipment, the use of reliable construction ② system is simple, flexible and convenient ③ fire speed, high efficiency ④ fire control system investment, fm certification gas fire, more economical.... ⑤. Wide application nozzle should be placed in the roof or ceiling easily accessible to the fire hot air and help position a uniform distribution of water. When there is an obstacle near the nozzle, it shall comply with this specification or additional compensation for water density of nozzles. Upright, pendent sprinklers arrangement, including with a water distribution manifold nozzle spacing and adjacent water distribution manifold spacing should be based on water density of the system, nozzle flow coefficient and pressure is determined not to be greater than in Table 7. 1.2 The provisions, and should not be less than 2.4m.