This part of ISO 4064|OIML R 49 specifies the metrological and technical requirements for water
meters for cold potable water and hot water flowing through a fully charged, closed conduit. These
water meters incorporate devices which indicate the accumulated volume.
In addition to water meters based on mechanical principles, this part of ISO 4064|OIML R 49 applies to
devices based on electrical or electronic principles, and mechanical principles incorporating electronic
devices, used to measure the volume of cold potable water and hot water.
This part of ISO 4064|OIML R 49 also applies to electronic ancillary devices. Ancillary devices are
optional. However, it is possible for national or regional regulations to render some ancillary devices
mandatory in relation to the utilization of water meters.
NOTE – Any national regulations apply in the country of use.
