NFPA 15 7.2.2. Cable Trays and Cable Runs
188.8.131.52 Where insulated wire and cable or nonmetallic tubing is to be protected by an automatic water spray(open nozzle) system designed for extinguishment of fire that originated within the cable or tube, the system shall be hydraulically designed to impinge water directly on each tray or group of cables or tubes at a net rate of 0.15 gmp/ft2[6.1 lpm/m2] on the projected plane containing the cable or tubing tray or run.
How much flow rate can be applied to cable duct in the attched file ?
Cable duct is enclosed and only signal cables are installed in the cable duct. Flow rate may be different compared with cable tray.