The National Institute of Standards and Technology (NIST) is a non-regulatory federal agency within the U.S. Department of Commerce.  The NIST Weights and Measures Division (WMD) is leading the effort to develop national and international weights and measures standards that will be required for commercial hydrogen refueling.

NIST WMD is working on three separate standards that apply to hydrogen applications.  Three separate U.S. National Work Groups (USNWGs) are forming to work on each project that cover two international standards (equipment measuring cryogenic liquids and compressed gaseous fuels for vehicles) and a third that will fully develop a U.S. hydrogen meter code(s).

NIST WMD  is seeking experts who develop related technical standards, manufacturers of equipment, or regulatory officials who have legal control over commercial measurement devices (especially in the area of hydrogen) to participate on all three USNWGs.  Expertise is needed to ensure national and international standards developed for these devices are adequate and suitable for U.S. commercial equipment and are harmonized to the greatest extent possible.  Many participants may have an interest in more than one work group because all three standards address the delivery of hydrogen (gas or liquid).

NIST WMD is responsible for representing the interest of U.S. stakeholders on International Organization of Legal Metrology (OIML) Recommendation 81 (R 81) "Dynamic Measuring Devices and Systems for Cryogenic Liquids."  In accordance with OIML Directive for Technical Work, R 81 is due for its periodic review.  NIST WMD requests input from interested parties on the appropriateness of the metrological and technical requirements and test procedures in R 81 by August 28, 2007 so a U.S. position can be established on whether or not this document needs an update.  R 81 and R 81 Annex D - Test Report Format are available on the OIML website at http://www.oiml.org/publications.

On a separate but related note, the first meeting of the USNWG for hydrogen measurement standards is scheduled for October 3-4, 2007, at NIST, Gaithersburg, Maryland.  The primary focus of that meeting will be a 2nd draft of the NIST Handbook 44 Hydrogen Gas Meters Code.  All three documents will be considered in that session since each includes requirements effecting U.S. commercial equipment used in hydrogen measurements in the national or international marketplace.

To participate in a USNWG, comment on the status of R 81, or get more information regarding the October 2007 meeting, please contact Juana Williams (NIST) by e-mail at This e-mail address is being protected from spambots. You need JavaScript enabled to view it .