General Sprinkler Installation Guidelines:
1. A cutoff room should be provided as the riser room housing alarm check valves and control valves and the room should be accessible from outside in case of any fire. As an alternative option, wall-mounted post indicative valves (WPIV) should be installed as control valves near the alarm check valves, or a post indicating valve (PIV) should be installed at the lead-in pipe to the riser.
2. Inspector’s test connections (ITCs) should be provided and connected from the most remote branch line ends for every system, directly extended to an open outdoor area, and must be readily accessible.
3. Adequate drainage should be provided for the 2-in. drain valves of the alarm check valves. They should be preferably connected to the outdoors directly and flows could be visible when conducting the test.
4. All control valves on sprinkler pipes should be installed in a position which is easy to access. All the control valves at the ceiling level should be removed or relocated.
As a minimum, the ceiling-level control valves should be installed upside down, so that the valve indicators could be inspected from the floor level.
5. Pressure reducing valves should not be used for the sprinkler systems.
6. The aboveground sprinkler pipe should be hydrostatically tested at not less than 14-bar pressure for two hours without any leakage prior to operation.
7. The sprinkler underground main should be hydrostatically tested under a pressure of 14 bars with allowable leakage determined as below: 3.8 L of water for every 100 joints of the underground pipe within two hours.
8. Proper clearance: The sprinkler heads should be installed with the centerline of the thermal sensing element located a maximum of 330 mm and a minimum of 102 mm below the ceiling. An acceptable alternative is to install the sprinkler so that the deflector is a maximum of 356 mm and a minimum of 127 mm below the ceiling. For K22.4 (K314) and the K25.2 (K360) pendent suppression mode sprinklers, the maximum clearance can be up to 425 mm.
The clearance between the top of the storage and the sprinkler deflector should be maintained at least 0.9 m.
9. Possible Obstructions
a. Obstructions are at the ceiling level: In general, the sprinklers should be located to meet the following requirements illustrated in Figure 31 and Table 18.
b. Beams and purlins, specifically, are the obstructions at the ceiling. If the above requirements (Figure 31) cannot be met, additional sprinklers on the other side of the beams meeting the following requirements regarding the distance from the beam should be installed. The maximum permitted H as shown in the following figure should be 1.5 m and is independent of V.
c. For obstructions to the inner core discharge pattern of ceiling-level storage sprinklers, install storage sprinklers as recommended in Table 20 and Figures 34 through 37 to avoid the sprinkler’s inner core distribution pattern being obstructed by individual objects located below the sprinklers.
d. Cable trays and ducts are obstructions below sprinklers. If they are continuous, flat, horizontal and solid, install a line of sprinklers with the thermal sensing elements located a maximum of 330 mm below the obstruction. Use the same type of sprinklers used at the ceiling, and space them a maximum of 2.4 m apart. Maintain at least 900 mm between the sprinkler deflector and the top of the storage.
e. If cable trays or ducts are continuous and not flat (as in the case of a circular duct) or is not solid (as in the case of grouped conduits), install a flat barrier under the obstruction at least as wide as the obstruction. Install a line of sprinklers below the barrier as described in the previous paragraph.
Typical Sprinkler Installation Deficiencies:
Sprinkler Installation Deficiency Example and Photo 1.Sprinkler obstructed by building structure beams 2.Sprinkler obstructed by building structure 3. Sprinkler obstructed by ductworks (over 0.6 m) 4. Storage Sprinkler obstructed by group pipes 5. Storage Sprinkler obstructed by lighting fixtures and cable trays 6. Storage Sprinkler obstructed by building wind bracings 7. Storage Sprinkler obstructed by air vent (over 0.6 m) 8. Storage Sprinkler obstructed by fire protection pipe itself 9. Additional sprinkler heads should be installed beneath the roof vents. 10. Exceed the clearance from storage sprinkler head to the ceiling