Discharge Table for Circular Outlets

Discharge Table for Circular Outlets* (U.S.)

	DIAMETER OF NOZZLE
In.	2-3/8	2-1/2	2-5/8	2-3/4	2-7/8	3	3-1/8	3-7/8	4*	4-3/8*	4-1/2*	4-5/8*
mm	60.3	63.5	66.7	69.9	73.0	76.2	79.4	98.4	101.6	111.1	114.3	117.5
PSI	U.S. Gallons Per Minute
1	150	170	180	200	220	240	260	400	430	510	540	580
2	210	240	260	290	310	340	370	570	610	720	770	810
3	260	290	320	350	380	420	450	700	740	890	940	990
4	300	340	370	410	440	480	530	810	860	1030	1090	1150
5	340	380	410	450	500	540	590	900	960	1150	1220	1290
6	370	410	450	500	540	590	640	990	1050	1260	1340	1410
7	400	440	490	540	590	640	690	1070	1140	1360	1440	1520
8	430	480	520	570	630	680	740	1140	1220	1450	1540	1620
9	450	500	550	610	670	730	790	1210	1290	1540	1640	1720
10	480	530	580	640	700	760	830	1280	1360	1630	1730	1820
11	500	560	610	670	730	800	870	1340	1430	1710	1810	1910
12	520	580	640	700	770	840	910	1400	1490	1780	1890	1990
13	550	610	670	730	800	870	950	1450	1550	1850	1960	2070
14	570	630	690	760	830	900	980	1510	1610	1920	2040	2150
15	590	650	720	790	860	940	1020	1560	1660	1990	2110	2220
16	610	670	740	810	890	970	1050	1620	1720	2060	2180	2300
17	620	690	760	840	910	1000	1080	1660	1770	2120	2240	2370
18	640	710	780	860	940	1030	1110	1710	1820	2180	2310	2440
19	660	730	810	890	960	1050	1140	1760	1870	2240	2370	2510
20	680	750	830	910	990	1080	1170	1800	1920	2290	2430	2570
22	710	790	870	950	1040	1130	1230	1890	2020	2400	2550	2700
24	740	820	910	1000	1090	1180	1290	1970	2110	2510	2660	2810
26	770	860	940	1040	1130	1230	1340	2050	2190	2620	2770	2930
28	800	890	980	1070	1170	1280	1390	2130	2280	2720	2880	3040
30	830	920	1010	1110	1210	1320	1430	2210	2350	2820	2980	3150
32	860	950	1050	1150	1260	1370	1480	2280	2430	2919	3080	3250
34	880	980	1080	1180	1290	1410	1530	2350	2510	3000	3170	3350
36	910	1010	1110	1220	1330	1450	1580	2420	2580	3080	3260	3440
38	930	1040	1140	1250	1370	1490	1620	2480	2650	3170	3350	3540
40	960	1060	1170	1290	1400	1530	1660	2550	2720	3250	3440	3630

(*)The stream from a large hydrant outlet 4" to 4�" contains voids (i.e., the entire stream of water is not solid), and for this reason the standard flow formulas alone will not give accurate results for flows using these larger steamer outlets. Generally, the 2�" outlets should be used. When a large outlet is used the standard formula answer must be multipled by the factor in the adjacent table to get a fairly accurate flow result.

To convert gallons to litres, multiply by 3.785.

Computed with Coeffcient C=90, to nearest 10 gallon per minute.
Table for "IFSTA" International Fire Service Training Association, Fourth Edition.

Correction Factors for Large Diameter Outlets

Correction Factors for Large Diameter Outlets
Velocity Pressure	Factor
2 psi (13.8 kPa)	0.97
3 psi (13.8 kPa)	0.92
4 psi (13.8 kPa)	0.89
5 psi (13.8 kPa)	0.86
6 psi (13.8 kPa)	0.84
7 psi (13.8 kPa) or over	0.83

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