ANSI/ASHRAE Standard 41.8 prescribes methods for liquid flow measurement and applies to laboratory and field liquid flow measurement for testing heating, ventilating, air-conditioning, and refrigerating systems and components.

The 2023 edition of Standard 41.8 includes updated methods for determining when steady-state operation has been achieved for data recording, changes to make it easier for higher-tier standards to adopt this standard by reference, and a new uncertainty example prepared in accordance with the latest uncertainty procedures.

Standard 41.8 meets ASHRAE's mandatory language requirements.