ISO 4064-2:2024

Overview

ISO 4064-2:2024 - Water meters for cold potable water and hot water - Part 2: Test methods - specifies the test programme, equipment, procedures and acceptance criteria for the type evaluation and initial verification of water meters intended for cold potable water and hot water. It supports conformity assessment (including issuance of OIML Certificates of Conformity when used with ISO 4064-1:2024|OIML R 49‑1:2024 and ISO 4064-3:2024|OIML R 49‑3:2024) and applies equally to ancillary devices and to separate metrological units such as the measurement transducer (flow/volume sensor) and the calculator/indicating device.

Key topics and requirements

ISO 4064-2:2024 defines detailed test procedures and verification principles. Major technical topics include:

• External examination: marking, inscriptions, indicating device, protection devices.
• Performance tests applicable to all meters:
  • Static pressure testing
  • Determination of intrinsic errors (of indication)
  • Water temperature and overload temperature tests
  • Water pressure and reverse-flow tests
  • Pressure loss (Δp) testing
  • Flow disturbance tests
  • Durability tests (discontinuous and continuous flow)
  • Magnetic field testing
  • Tests on ancillary devices and software evaluation
• Environmental and influence-factor testing: classification and tests for dry heat (non‑condensing), cold, damp heat (condensing), electromagnetic and other environmental stresses.
• Test planning: reference conditions, required test volumes for error determination, equipment setup and acceptance criteria.
• Modular testing: provisions for testing metrological modules and interchange tests for cartridge/exchangeable modules.

Practical applications and users

ISO 4064-2:2024 is intended for:

• Meter manufacturers - product development, type approval testing and design verification.
• Test laboratories and conformity assessment bodies - carrying out type evaluation and initial verification according to internationally harmonized methods.
• National metrology institutes and regulators - defining regulatory verification procedures and enforcing meter performance requirements.
• Utilities and installers - understanding meter performance limits, installation influences and acceptance criteria.
• Certification schemes (OIML) - basis for issuing certificates when combined with the related parts of ISO 4064/OIML R 49.

Practical uses include type testing during product introduction, acceptance testing of new meter batches, troubleshooting performance deviations, and demonstrating compliance for market access.

Related standards

• ISO 4064-1:2024 | OIML R 49‑1:2024 - General requirements and definitions for water meters.
• ISO 4064-3:2024 | OIML R 49‑3:2024 - Test procedures for statutory and pattern approval (complementary requirements).

Keywords: ISO 4064-2:2024, water meters, test methods, cold potable water, hot water, type evaluation, initial verification, pressure loss, intrinsic errors, durability tests, environmental testing, OIML certificate.