Flow and Volume of water
Realisation of the Units of Flow and the Volume of Water
BEV realises water flow with a test bench that can produce water flows from 6 L/h to 180 000 L/h with a stability better than 0.2%. For all flow measurements the temperature can be set between 2.5 °C and 90 °C; in closed loop mode (pressure mode) even until 130 °C.
The volume of running water is measured with flow meters whose accuracy has been examined with volume meters. The volume of these instruments is determined gravimetrically, which means through weighing.
Verification of Water meters
Water meters are subject to verification in Austria.
The first verification of a new instrument is called initial verification. The verification of an unverified instrument is a new verification. Verification within the validity period is called reverification.
The Measuring Instruments Directive (MID) has been applied in all EU Member States since October 30, 2006.
This Directive regulates the launching onto the market of measuring instruments liable to verification through conformity assessment procedures. Water meters are included in the MID. Therefore they may be put into use for the first time without further national type approval or initial verification. The assessment of the conformity is equivalent to the initial verification.
Modules B+D, B+F and Conformity assessment procedure H1 are applicable to water meters.
Water meters which do not fall under this directive are subject to the national regulations as before. Besides the national pattern approval there exists also an EEC-type approval under the European Economic Area Agreement (EEA-Agreement).
New and subsequent verification of water meters are at any rate subject to national regulations. They are performed by accredited/authorized verification bodies.
The reverification period for water meters is 5 years. An extension of that period is not possible at present.