Analiza metod określania natężenia przepływów maksymalnych w budynkach wielorodzinnych

The water works authorities and designers claim that applying standards of PN-92/B-01706 from the year 1992 and PN-ISO 4064-2 causes difficulties in choosing a size of water meter for a residential building. They accuse the standard from the year 1992 of overdimensioning a size of water meters and they accuse PN-ISO 4064-2 that apart from general records there are not any computational formulas that make us closer to calculate the real characteristic flows. Research of flows sizes in buildings within the years 2002÷2005 were carried out in 120 multi-occupied buildings, located in different towns in Poland supplied directly from the municipal water works or hydrophores (pumps controlled using frequency converter or inverter). Each connection with network was equipped with the water meter about the diameter selected tentatively to expected flows and water consumption. They were also adapted by the producer for transmitters of impulses in order to enable connection of the digital recorder. The size of impulses was different and it was adapted for the size of buildings (1÷100 of litres). On the basis of obtained results statistical method to calculate a quantity of flow in a function of parameters that are characteristic of multiroom buildings i.e.: a number of rooms LL, a number of occupants LM., water consumption (per month and per day) was worked out. Results of statistical method were compared with the results received on the basis of standards and law regulations in force. The simulation method of water meters selection is being realized in practice in a dozen or so waterworks companies with very good results. It lets to make apparent losses smaller about 5÷10% although there are also much higher effects. The appropriateness of such conduct is evident in waterworks companies but in many cities administrators of buildings resist this conduct, seeing the danger connected with it. Above all it concerns expanding differences between main water meters - waterworks, and total consumption from household water meters. Apart from that administrators say that according to standard from 1992 there are practically no other legal regulation in force as well as they demand more clearly documentary evidence of the fact of water meter diameter change. However it seems, that both monitoring as well as the simulation method - derivative of monitoring approaching the standard PN-ISO 4064-2 appointed after for use in the directive of the minister of infrastructure.