All material while unloading shall be lowered to the ground either manually or with crane. For pipes, timber supports shall be placed beneath at equal distance. Pipes shall be stacked on a flat surface with adequate supports. While stacking, it shall be ensured that pipes of bigger sizes are placed below and smaller sizes on top. All pipes shall be covered and shall not be exposed to direct sunlight.
All other items such as valves, gauges, switches shall be kept on racks within site stores and shall be segregated as per size, model, type etc. for easy retrieval. Any items found damaged or not suitable as per project requirements shall be removed from site.
Preparation for Installation Works
Check and ensure all drawings used for firefighting piping installation are latest and approved for construction. Check the coordination of piping layout with other services and reflected ceiling and resolve problems, if any. Mark the pipe routing on the ceiling as per approved drawings.
Installation Procedure for firefighting piping
Fix supports and hangers with approved material, as per approved layout drawings. Cut all excess hanger rods to leave only 25mm lengths below the support for final adjustment of levels, if required. Machines cut the pipes square to required length and ream the pipes to remove burrs and clean thoroughly before installation. Pipe work up to 50mm shall have threaded joints and pipes 65mm and above shall be with grooved coupling joints.
Install firefighting pipe work at heights and to gradients shown on approved drawings, in a neat and tidy manner. Hole saw cutter shall be used to cut holes in the pipe work where required for fixing mechanical Tees etc. PVC Sleeves of suitable sizes shall be provided at wall crossings and fire stopping with approved material shall be completed.
Only standard fittings shall be used for changes in directions, reduction in pipe sizes, Tee joints, etc. Expansion couplers shall be installed at location where piping crosses the building expansion joints. All vertical firefighting pipes shall be installed plumb with at least 25mm clearance from the wall / surface. Install valves, supervisory switches, flow switches, pressure gauges etc. as per approved drawings and manufacturer’s instruction.
Install drain valves at all low points as shown on approved drawings and ensure that water can be drained from all sections of pipe work. Inspectors test drain valves of suitable size shall be provided at the farthest point in the system in each zone as per approved drawings. Check and ensure easy access is available for maintenance and removal of all components such as valves, switches etc.
The droppers for sprinkler heads are installed at location as per approved layout / coordinated drawings. Plug or cap-off all open ends in the piping during the installation phase. Flush and clean the entire piping with clean water until the system is clean. Install correct type of sprinkler heads as per approved drawings and manufacturers instruction. Clean the pipe work thoroughly to remove all dirt, soil, oil, etc. and apply one coat of primer. Provide identification and flow directional arrows to the pipe work, valves and other components as per approved submittals / details.
The entire firefighting installation shall be supervised, checked and certified by sub-contractor prior to testing and commissioning of the system. The details of the entire installation of the system shall be inspected and approved by the Dubai Civil Defense Authority.
The entire firefighting pipe work shall be hydro-statically pressure tested at 1.5 times the working pressure of the system. The final testing and commissioning of the system shall be carried out as per separate method statement. Work Inspection Request shall be raised for Consultant’s inspection and sign off.