BS EN 15767-2:2009 pdf download – Portable equipment for projecting extinguishing agents supplied by fire fighting pumps — Portable monitors Part 2: Water nozzles

BS EN 15767-2:2009 pdf download – Portable equipment for projecting extinguishing agents supplied by fire fighting pumps — Portable monitors Part 2: Water nozzles 4.1.3 Flow adjustment positions The settings of the water nozzle equipped with selectable flowrate shall be easily identifiable by visual means. 4.1.4 Jet adjustment positions The different jet positions of a nozzle equipped with adjustable jet positions shall be clearly marked. 4.2 Materials The materials used shall be selected in such a way that all the requirements in Clause 4 are met, subject to the tests defined in Clause 5. The water nozzle shall pass the heat and frost tests defined in 5.3. 4.3 Flush 4.3.1 The combination nozzle with Q max less than 2 000 l/min, when tested in accordance with 5.4, shall be able to clear or flush a steel ball of 6,35 mm diameter without shutting off the nozzle. NOTE This should be accomplished either through the full open nozzle position or through a flush feature of the nozzle. In nozzles with flowrate over 2 000 l, blockage due to debris is not likely because of the larger opening of the nozzle. 4.3.2 Water nozzles equipped with a flush feature shall have a mechanical and/or visual device to indicate to the user when the flush feature is being engaged. 4.4 Hydraulic characteristics 4.4.1 Pressures The following pressures, measured at the nozzle inlet, shall be used for the determination of the hydraulic characteristics: reference pressure: p R = 6 bar ± 0,1 bar; median pressure for automatic water nozzle: p m ; nominal pressure: p N = 1 6 bar; test pressure: p t = 25,5 bar. 4.4.2 Flowrates All flowrates indicated on the nozzle shall be measured at straight jet and at the maximum spray angle position at the reference pressure p R . The flowrates measured at the reference pressure p R shall not deviate by more than – 0/+ 1 0 % of the flowrate setting of the nozzle. NOTE The deviation should also apply when the shape of the stream is altered. 4.4.3 Effective throw The water nozzle shall achieve, for each flowrate position above 500 l/min, a minimum effective throw d eff as shown in Figure 1 , when set to a straight jet at the reference pressure. For water nozzles above 4 000 l/min, the minimum effective throw shall be at least 60 metres. 4.4.4 Spray jet The...