OIML R 81
Dynamic Measuring Devices and Systems for Cryogenic Liquids
Published
International


 

Organization

International Organization of Legal Metrology (OIML)


Identification

OIML R 81

Dynamic measuring devices and systems for cryogenic liquids

 

OIML R 81-1: Metrological and technical requirements

OIML R 81-2: Metrological controls and performance tests

OIML R 81-3: Test report format


Scope

This Recommendation prescribes the metrological and technical requirements and test procedures for measuring devices and systems used for the dynamic measurement of cryogenic liquids.

 

In general, this Recommendation applies to all devices used for the continuous dynamic measurement of cryogenic liquids (including, but not limited to argon, ethylene, hydrogen, nitrogen and oxygen). This Recommendation applies specifically for the quantitative flow measurements of cryogenic liquids, whatever the measurement technology, whether installed in a permanent location, or mounted for use in transport and/or other containment vessel or tanks.

This Recommendation establishes the conditions that measuring devices and systems shall meet to comply with the requirements of legal metrology services.

 


Status

Published 1998. Available for downloading (free) at www.oiml.org

 

There is an active revision underway. The Recommendation has been significantly edited to include technical changes to reflect the latest: (1) ISO and IEC standards, (2) developments in cryogenic hydrogen measurement, (3) density equations, (4) requirements for software-controlled instruments, and (5) other relevant standards and national documents. A first Committee Draft was distributed in 2016. All comments received have been resolved. It is anticipated that a second Committee Draft will be distributed in 2020.

 

                


Committee
Information

OIML TC8 Measurement of quantities of fluids

OIML TC8/SC6 Measurement of cryogenic liquids

 

 

Secretariat

-        Ralph Richter , NIST, USA