What is ISO 4064-4 – Non-metrological requirements of water meters about? 
ISO 4064 is an International Standard that discusses water meters for cold potable water and hot water. ISO 4064-4 is the fourth part of the International standard ISO 4064 that aims to provide non-metrological requirements for water meters to ensure stable operability, compatibility with systems and prevention of failures.
ISO 4064-4 applies to water meters used to meter the volume of cold potable water and hot water flowing through a fully charged, closed conduit. These water meters incorporate devices that indicate the integrated volume.
ISO 4064-4 specifies technical characteristics and pressure loss requirements for meters for cold potable water and hot water. ISO 4064-4 applies to water meters that can withstand:
- A maximum admissible pressure (MAP) equal to at least 1 MPa) [0.6 MPa for meters for use with pipe nominal diameters (DNs) ≥ 500 mm]
- A maximum admissible temperature (MAT) for cold potable water meters of 30 °C
- A MAT for hot water meters of up to 180 °C, depending on the class
In addition to meters based on mechanical principles, this part of ISO 4064 also applies to water meters based on electrical or electronic principles, and to water meters based on mechanical principles incorporating electronic devices, used to meter the volume flow of hot water and cold potable water.
ISO 4064 also applies to electronic ancillary devices. As a rule, ancillary devices are optional. However, national or international regulations may make some ancillary devices mandatory concerning the utilization of the water meter.
Who is ISO 4064-4 - Non-metrological requirements of water meters for?  
ISO 4064-4 on non-metrological requirements of water meters form is relevant to: 
- Manufacturers of water meters
- Testing labs for water meters
- Product designers and specifiers
- Quality control and testing personnel
- Inspection and maintenance personnel
- Regulatory authorities
Why should you use ISO 4064-4 - Non-metrological requirements of water meters? 
Water meters are required to maintain equal distribution of water resources to the household. Irregularities in water meters may lead to irregular water supply leading to wastage of water. For proper inline functioning of water meters, consideration of non-metrological aspects is important.
ISO 4064-4 provides you guidance on water meter dimensions for threaded and flanged connections depending on tolerance on length, height, width and preferred and alternate values of length, enabling you to standardize the dimensional aspect of water meters and compatibility with existing systems.
ISO 4064-4 provides you guidance on the technical characteristics of in-line meters, concentric and cartridge meters and exchangeable metrological modules, enabling you to design and assess water meters to improve their performance and efficiency.
The guidance in ISO 4064-4 enables you to design and assess non-metrological requirements of water meters to ensure uniform water distribution and reduction of water wastage.
