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Application Model F1 Res Sprinklers are used for Residential Fire Pro- K=7.6)that will provide lower pressure demands for tection according to UL 1626 Standard. Be sure that orifice 0.1 gpm/ft' densities in NFPA 13 residential applica- size, temperature rating, deflector style and sprinkler type tions. are in accordance with the latest published standards of Example No. 1 The National Fire Protection Association or the approving Room Size= 12 ft x 20 ft(3.6 m x 6.1 m) authority having jurisdiction. Coverage Area= 12 x 20 = 240 ft2(22.3 m2� When using F1 Residential Sprinklers for systems designed Flow C�0.10 gpm/ftz density= 240 x 0.10 = � 4 gpm to NFPA 13D or NFPA 13R, use listed area of coverage and Using an F1 Res 49 Pendent Sprinkler, K=4.9 minimum fiow and pressure requirements shown in Bulletin Pressure= (24/4.9)� = 24 psi (1.65 bar) 135. The baseline flow for a 20 ft x 20 ft(6.1 m x 6.1 m)cover- For systems designed to NFPA 13, use information in this age area using the baseline density of 0.05 gpm/ft� will bulletin. The number of design sprinklers shall be the most be 20 gpm C� 16.7 psi (75.7 L/min C�3 1.14 bar). There- hydraulically demanding sprinklers as required by NFPA fore, the minimum flow required is 24 gpm Ca�24 psi(90.8 13. Flows and pressures can not be below the baseline L/min Ca� 1.65 bar}, flows and pressures. NFPA 13 Example No. 2 For residential sprinkler systems designed to NFPA 13, a �oom Size= 8 ft x 20 ft(2.4 m x 6.1 m) minimum density of 0.1 gpm/ft' must be provided aver the Coverage Area= 8 x 20 = 160 ft�(14.9 m2) "design area" that includes the four (4) hydraulically most Flow @ 0.10 gpm/ft�density= 160 x 0.10 = 16 gpm demanding sprinklers for the actual coverage areas being Using an F1 Res 49 Pendent Sprinkler, K=4.9 protected by the 4 sprinklers. The minimum required dis- Pressure= (16/4.9)� = 10.7 psi (0.74 bar) charge from each of the four most hydraulically demanding The baseline flow for a 20 ft x 20 ft(6.1 m x 6.1 m)cover- sprinklers shall be the greater of the following: age area using the baseline density of 0.05 gpm/ft� will 1. The flow rates given in the Reliable Residential be 20 gpm Ca� 16.7 psi(75.7 L/min @ 1.14 bar). Therefore, Sprinkler Technical Bulletins referenced in Table A the minimum flow required is 20 gpm @ 16.7 psi (75.7 for NFPA 13D and 13R as a function of temperature L/min Q 1.14 bar). rating and maximum ailowable coverage area (for Example No. 3 actual coverage areas less than or between those Room Size- 10 ft x 16 ft(3.0 m x 4.91 m) indicated in the respective technical bulletin, it is re- Coverage Area= 10 x 16 - 160 ft2 (14.9 m�) quired to use the minimum required flow for the next Flow C�3 0.10 gpm/ft�density= 160 x 0.10 - ��o gpm largest coverage area); or ? Using an F1 Res 76 Pendent Sprinkler, K=7.6 2. A minimum discharge density of 0.1 gpmift applied The baseline flow for a 16 ft x 16 ft coverage area is 21 over the"design area"consisting of the four most hy- gpm @ 7.6 psi (79.5 L/min C� 0.52 bar). Therefore, the draulically demanding sprinklers for the actual cov- minimum flow and pressure is 21 gpm C�? 7.6 psi (79.5 erage areas being protected by the four sprinklers. L/min C� 0.52 bar). The maximum dimension of the actual coverage area cannot be any greater than the maximum coverage Example No. 4 area indicated in the technical bulletins referenced Room Size- 14 ft x 18 ft(4.3 m x 5.5 m) in Table A. Design Note: Using the As = S x L method to de- Coverage Area= 14 2 18 = 252 ft'(23.6 m2) termine the sprinkler protection area of coverage in Flow @ 0.10 gpm/ft density= 252 x 0.10 = 25.2 gpm accordance with NFPA 13,apply the 0.1 gpm/ft'den- �94.6 L/min) sity to this area to determine the minimum required Using an F1 Res 76 Pendent Sprinkler, K=7.6 flow. Compare this flow to the minimum 0.05 gpm/ftz Pressure= (252/7.6)� = 11 psi (OJ6 bar) cULus Listed flow for the appropriate coverage area The baseline flow and pressure of an 18 ft x 18 ft cover- in the technical bulletin for the specific residentiai age area is 21 gpm @ 7.6 psi (79.5 Llmin Ca� 0.52 bar). sprinkler. If the flow stated in the technical bulletin Therefore, the minimum flow and pressure is 25.2 gpm C� is less than the calculated 0.1 gpm/ft=density flow 11 psi (94.6 L/min @ 0.76 bar). required,the.1 densiry flow must then be used in the In general residential sprinklers require flows and equation Q=KvP, solving for P, to establish the mini- pressures as listed for 0.05 densities to achieve the mum required pressure using the sprinkler K-factor. proper spray pattern so the flows and pressures at Note: In many cases the listed flow of individual resi- 0.05 density are the baseline flows and pressures. dential sprinklers may exceed the required minimum Flows and pressures below the listed 1 .05 density 0.05 gpm/ftz density. Reliable has available resi- shall not be used. dential sprinklers with larger K-factors (K=5.8 and 2.