JUNE 2007 

What's Next in Hydrogen? 

By Juana Williams

Work at NIST Weights and Measures Division (WMD) to develop legal metrology standards for hydrogen (H2) 

refueling stations is expanding. In March 2007, WMD received funding as part of the American Competitiveness 

Initiative for its work in support of the U.S. transition to a hydrogen economy. This is the first in a series of articles 

on the status of WMD's work, related hydrogen issues, and information of interest to the weights and measures 

community. 

Over the past four years Juana Williams, representing WMD and NIST, has participated in the National Hydrogen 

Fuel Cells Codes and Standards Coordinating Committee (NHFCCSCC). The NHFCCSCC is sponsored by the 

U.S. Department of Energy National Renewable Energy Laboratory, National Hydrogen Association, and U.S. Fuel 

Cell Council. The NHFCCSCC coordinates the development and implementation of a uniform set of H2-related 

codes to ensure the safe production, delivery, and use of H2. This collaborative effort was undertaken to make it 

possible for the commercialization of H2 technology in stationary, transportation, and portable applications. The 

NHFCCSCC also collaborates with other national and international organization conducting similar H2 work. 

Currently WMD is creating a long-range plan for the development of commercial H2 measurement standards that 

encompasses: (1) codes; (2) method of sale requirements; (3) marking and labeling requirements; (4) quality; (5) 

sampling procedures; (6) inspection procedures, equipment suitability, and safety; (7) training for officials and 

service companies; and (8) education on H2 measurement. WMD will need to accelerate its work to stay ahead of 

emerging technology and to have standards in place when the public is permitted access to H2 refueling stations. 

WMD plans to establish a U.S. National Work Group (USNWG) of industry and regulatory experts as well as 

conduct educational workshops on H2 measurement. Part of its outreach will be to the 17 States that already have 

refueling dispensers operating in support of fleet and other fuel cell vehicles. 

WMD and other organizations are already at work on several standards in those key areas. In 2005 WMD 

developed and distributed a first draft of an H2 Gas Meters Code. The first draft is currently posted at 

www.fuelcellstandards.com and is based on existing technical requirements and test procedures that apply to other 

commercial measuring devices similar to those used in the delivery of hydrogen. To date comments from industry 

indicate the 1.5 % acceptance tolerance based on NIST Handbook 44 Section 3.37 Mass Flow Meters Code 

requirements for Accuracy Class 2.0 devices used to meter compressed natural gas (CNG) as a motor-fuel is too 

stringent. Additionally, standards may be needed to address equipment that dispenses liquid H2 or a CNG and H2 

blend. Other agencies such as the California Division of Measurement Standards are working to establish a quality 

standard for H2 used by fuel cell vehicles. The multitude of national and international groups working on H2 

projects offers many opportunities for collaboration and will continue to require coordination of our efforts to avoid 

redundancy and nonuniform standards. 

WMD has tentative plans for an August 2007 USNWG meeting and a September 2007 educational workshop. 

Involvement of weights and measures administrators, officials, and industry experts will be essential to developing 

appropriate and fair weights and measures standards. WMD will keep all stakeholders posted on these upcoming 

activities. 

If you have questions about the standards development process or are interested in participating in a work group or 

workshop, please contact Juana Williams by email at juana.williams@nist.gov or by telephone at 301-975-3989.