Historical data will be extensively analysed as part of the research project and measurements taken on the accuracy of water meters beyond the end of the calibration period to provide the basis for an informed discussion on adapting the calibration periods of water meters.
According to German calibration regulations, the calibration period of residential meters differs depending on their use in cold water and hot water. The meter calibration period is 6 years for cold water and 5 years for hot water. Taking the sampling procedure into consideration (extension of the calibration period by 3 years), Germany has a relatively short service life for its meters at approx. 7.5 years compared with other European countries, where meters are used for longer than 10 years. This is despite the fact that the European directive (MID, Measuring Instruments Directive) stipulates the same rules for water meters being placed on the market.
The water supply sector has an obligation to only place reasonable costs on customers and to ensure operation that conserves resources. Compared with other media, there are high costs for changing drinking water devices in comparison with the medium measured during the operation period. The challenge is therefore to potentially extend or provide greater flexibility for the calibration periods of water meters.
Comprehensive assessments are required in order to have a well-informed discussion about potentially adjusting the water meter calibration periods. For this reason, historical data will be extensively analysed as part of the research project and measurements taken on the accuracy of water meters beyond the end of the calibration period.