3. Where the suction supply is of sufficient pressure to be of material value without the pump, the pump shall be installed with a by-pass. 4. A listed outside screw and yoke (OS&Y) shall be installed in the suction pipe. No valve other than a listed OS&Y valve shall be installed in the suction pipe within 50 ft of the pump suction flange. 5. The pump arrangement should be designed such that, when the pump is operating at 150% of rated capacity, the velocity in the portion of pipe located within 10 pipe diameters upstream of the suction flange does not exceed 15 ft/sec. 6. The performance of all fire pumps and booster pumps should be automatically indicated on a pressure recorder having either reliable electric drive or mechanical spring driven drive. 7. A separate controller and pressure sensing line should be provided for each pump, including the jockey pump. In general, the pressure sensing line should be arranged as follows: a. The line should be of the ½ in. nominal size made of either copper or brass. There shall be two check valves installed in the pressure sensing line at least 5 ft apart with a 3/32 in. hole drilled in the clapper to serve as dampening. b. There should be no shut-off in the pressure sensing line. 8. The fire pump system, with start by pressure drop, should be arranged as follows: a. The jockey pump stop point should equal the pump churn pressure plus the minimum static supply pressure (based on a full water tank). b. The jockey pump start point should be at least 10 psi less than the jockey pump stop point. c. The fire pump start point should be 5 psi less than the jockey pump start point. 9. The fire pump should be arranged for manual stopping only. An automatic run- timer should not be used. 10. Suction and discharge piping shall be hydrostatically tested at not less than 200 psi pressure. The pressure shall be maintained for 2 hours. Pressure loss should be determined by drop in gauge pressure or visual leakage. 11. The FM Global Red Tag Permit System should be utilized to supervise any valve closures during the pump installation. 12. Final acceptance of the pump installation will be upon satisfactory field examination by an FM Global representative. Sufficient time should be provided between notification and the test so that necessary information can be provided to the FM Global representative. The pump manufacturer, the driver manufacturer,
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