USNWG COMMERCIAL H2 MEASMT STANDARDS 

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U.S. National Work Group 

for the 

Development of Commercial Hydrogen Measurement Standards 

March 4-6, 2008 

California Fuel Cell Partnership (CaFCP) 

West Sacramento, California 

DEVICE STANDARDS AND TEST PROCEDURES SUBCOMMTTEE (DSTPS) 

and 

FUEL SPECIFICATIONS SUBCOMMITTEE (FSS) 

MEETING SUMMARIES 

Subcommittee meetings are sponsored by the U.S. Department of Energy (DOE) and U.S. Department of 

Commerce's National Institute of Standards and Technology (NIST). 

Purpose: The U.S. National Work Group (USNWG) Subcommittees met to continue their work to 

promote the establishment of a comprehensive set of (1) design, accuracy, installation, use, and method of 

sale requirements, (2) test procedures, and (3) quality standards for equipment used in hydrogen 

measurements for vehicle and other refueling applications. 

Background/History: 

At its October 2007 meeting the USNWG agreed that the development of device and fuel standards could 

best be accomplished by two separate subcommittees. The Device Standards and Test Procedures 

Subcommittee (DSTPS) and Fuel Specifications Subcommittee (FSS) met in March 2008 on different dates 

with each subcommittee having separate agendas. The Subcommittees will continue this practice for future 

sessions. 

AGENDA ITEMS 

Page 

Attachments List – Appendices A-M ........................................................................................................ 2

Note: Appendices A-L to the Meeting Summaries are available on request. 

Device Standards and Test Procedures Subcommittee 

(1) Welcome and Introductions ................................................................................................................ 3

(2) Administrative Business ....................................................................................................................... 3

 (a) Approve the Summary of the October 2007 USNWG Meeting ..................................................... 3

 (b) Approve the USNWG Guidelines ..................................................................................................... 3

 (c) Elect a USNWG Chairperson............................................................................................................ 3

(3) Development of Device Standards and Test Procedures for Commercial Hydrogen 

Measurement............................................................................................................................................... 3

(4) Next Steps/Tasks.................................................................................................................................... 9

(5) Next Meeting........................................................................................................................................ 10

(6) USNWG – Technology Tours........................................................................................................... 10

Fuel Specifications Subcommittee 

(1) Welcome and Introductions .............................................................................................................. 10

(2) Background and History ............................................................................................................... . . 11
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(3) Method of Sale for Hydrogen Dispensing Applications................................................................... 12 

(4) Engine Fuel Quality ........................................................................................................................... 13 

(5) Accurate Measurement of Water Vapor Concentration ................................................................ 13 

(6) Laboratory Manual............................................................................................................................ 13 

(7) Field Sampling Procedures................................................................................................................ 14 

(8) Next Steps............................................................................................................................................ 14 

(9) Next Meeting........................................................................................................................................ 14 

Attendee List – Appendix M .................................................................................................................... 15 

ATTACHMENTS LIST 

Appendix Related Agenda 

Item(s) 

Title 

A (2)(a)*and** Summary of the October 2007 USNWG Meeting

B (2)(b)*and** USNWG Guidelines 

C (3)* Draft 2.1 of NIST Handbook 44 Gas Meters Code

D (3)* Comments on the 2nd Draft of the NIST Handbook 44 Hydrogen 

Gas Meters Code (27 Sep2007) – Buttler (Micro Motion)

E (3)* Comments on 2nd Draft of the NIST Handbook 44 Hydrogen Gas 

Meters Code (03Oct07) – Cohen (Air Products and Chemicals, 

Inc.)

F (3)* OIML R 81 "Dynamic Measuring Devices and Systems for 

Cryogenics Liquids"

G (3)* OIML R 139 "Compressed Gaseous Fuel Measuring Systems for 

Vehicles"

H (4)-(7)** California Division of Measurement Standards Proposal for an 

Interim Specification for Hydrogen Fuel (03Mar2008 version 

replaces the Feb2008 version distributed to the USNWG) 

I (3)* Comments on the 2.1 Draft of the NIST Handbook 44 Hydrogen 

Gas Meters Code (05Mar2008) – Nelson (California Division of 

Measurement Standards) 

J (3)* Summary of Comments on Drafts 2.0 and 2.1 

K (3)* California Fuel Cell Partnership How It Works Brochure 

(Available through the CaFCP @ www.fuelcellpartnership.org)

L (3)* California Fuel Cell Partnership Station Tour Presentation 

M Attendee List 

* Device Standards and Test Procedures Subcommittee 

** Fuel Specifications Subcommittee 
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DEVICE STANDARDS AND TEST PROCEDURES SUBCOMMITTEE (DSTPS) MEETING 

Tuesday-Wednesday, March 4, 2008, 8:30 a.m. – 5:00 p.m. (PT) 

California Fuel Cell Partnership, 3300 Industrial Blvd., Dr. Lloyd Conference Room 

West Sacramento, CA 95691 

Moderator – Juana Williams (NIST WMD) 

(1) Welcome and Introductions 

The Moderator welcomed the participants, called the meeting to order, and covered the meeting objectives. 

The collaborative work by the meeting's sponsors, DOE and NIST, was recognized. Participants were 

briefed on the facilities available at the CaFCP, the schedule of events, meeting procedures, and materials. 

Participants provided their name, affiliation, and stated their specific area of interest in the work to develop 

hydrogen measurement standards (See Appendix M). 

(2) Administrative Business 

The DSTPS discussed procedures for managing the work group and its’ subcommittees and documenting its 

technical work. The following items were addressed: 

(a) Approve the Summary of the October 2007 USNWG Meeting 

The October 2007 Summary was approved after changes were made to reflect that the SAE document 

on hydrogen quality is a technical information report rather than a standard. 

(b) Approve the USNWG Guidelines 

The DSTPS Technical Advisor requested the Subcommittee review the draft USNWG Guidelines and 

submit their comments by March 25, 2008. The guidelines describe the work group and its 

subcommittee’s objectives, general membership, meeting and voting procedures, and timelines for 

projects and other tasks. The Technical Advisor will electronically ballot the DSTPS for their approval 

of future drafts of the guidelines. 

(c) Elect a USNWG Chairperson 

The DSTPS elected Kristin Macey, California Department of Food and Agriculture, Division of 

Measurement Standards (CDFA/DMS). The Chair acts in a national capacity to ensure the work 

progresses satisfactorily and in a timely fashion to develop appropriate legal metrology standards. 

(3) Development of Device Standards and Test Procedures for Commercial Hydrogen Measurement 

The USNWG is working within an existing network of experts in the weights and measures and hydrogen 

communities to develop a set of standards that are appropriate for commercial hydrogen measurements. 

The DSTPS is focusing on commercial hydrogen measurement standards necessary to support the hydrogen 

economy that include: (1) device and related equipment codes, (2) inspection procedures, test equipment 

standards, and safety practices, (3) training for officials and service companies, and (4) education of the 

public on hydrogen measurement. The DSTPS was advised that a variety of metering technologies, such as 

mass flow meters and sonic nozzles might at some point need to be addressed in the codes. The DSTPS 

resumed work on Draft 2.1 of the NIST H44 Hydrogen Gas Meters Code addressing the October 2007 and 

March 2008 comments (see Appendices D, E, and I, or J) the Subcommittee received on the code. 
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The DSTPS made changes to draft 2.1 of the NIST Handbook 44 Hydrogen Gas Meters Code based on 

comments from industry and Weights and Measures officials to address: (1) marking temperature ranges; 

(2) pressurization of the hose; (3) units of measurement; (4) selection of the unit price; (5) receipt 

requirements in retail applications; and (6) the appropriate flow rate for a performance test at the declared 

minimum measured quantity (Buttler, Keilty, Richter will provide feedback). The draft will also be revised 

to clarify how product composition relates to meter technology and to define the terms nonresettable 

totalizer and minimum measured quantity. A third draft code that incorporates all of the changes noted 

above and in the table below will be made available for electronic review by the DSTPS shortly.

The DSTPS discussions covered the following topics: 

Industry and Other Standards 

The DSTPS has concerns about the differences in standard conditions recognized by various standard 

bodies, groups, and organizations. The unit of measurement in use to identify pressure on dispensing 

system is the “bar.” The DSTPS is recommending use of the conversion factor of 1 bar = 14.5 psi, which is 

recommended by the Canadian Standards Association. 

Test Procedures and Test Data 

Several dispenser OEMs are working to provide performance data to the DSTPS for comparison with 

current accuracy requirements in the draft code. CDFA/ DMS is nearing completion of a checklist 

procedure for approving dispensers and working to obtain a mobile gravimetric test unit so that CDFA/ 

DMS can begin gathering data. With over 20 hydrogen stations, CDFA /DMS anticipates it will be the first 

state to receive a request for approving a hydrogen dispenser for commercial use. The USNWG had lengthy 

discussions about (1) how to simulate real world filling conditions to 1/3, 2/3, and 3/3 vehicle tank capacity, 

(2) test dispenser accuracy using either a gravimetric, volumetric, or transfer standard. It is anticipated that 

field test procedures for commercial equipment will be the primary focus of the upcoming May/June 2008 

meeting. 

The DSTPS has concerns about control of the delivery to simulate the required flow rates and quantities 

during test of the systems. The DSTPS discussed the ability of laboratories and field officials to throttle 

tank valves or vent tanks to control delievery rates. Systems operating at 700 bar would not allow for 

throttling the test tank valves since the filling is off the compressor. The DSTPS will consider a 

recommendation for using a small tank to simulate fill into an almost full tank and for performance tests at 

the minimum measured quantity. 

Test Standards 

The DSTPS agreed to include text to recognize transfer standards. The DSTPS Technical Advisor noted 

that a NIST 105 Series (Specifications and Tolerances for Reference Standards and Field Standard Weights 

and Measures) for master meters is only in the early stages of development. 

Code Revisions 

Paragraphs modified by the DSTPS during the March 2008 meeting and the rationale for their actions are as 

follows: 

March 2008 DSTPS Modifications to Draft 2.1 of the NIST Handbook 44 Hydrogen Gas Meter Code 

Change to Requirement: Added 

Example to Paragraph S.1.3.2. 

Requirement Title: Numerical 

Value of Quantity-Value 

Divisions 

Reason for Change: Clarified 

the difference between an 

acceptable numerical value and 

units of measurement for 

quantity divisions 
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S.1.3.2. Numerical Value of Quantity-Value Divisions. - The value of a scale interval shall be 

equal to: 

- 1, 2, or 5, or 

- a decimal multiple or submultiple of 1, 2, or 5. 

 

 Examples: quantity-value divisions may be 10, 20, 50, 100; or 0.01, 0.02, 0.05; or 0.1, 

0.2, or 0.5 etc.

Change to Requirement: Modified 

Paragraph S.2.7. 

Requirement Title: Recorded 

Representation, Point of Sale 

Systems 

Reason for Change: 

Clarify that a printed sales 

receipt is required on hydrogen 

motor-fuel systems 

 

S.2.7. Recorded Representations, Point of Sale Systems. – A printed receipt shall be available 

through a built-in or separate recording element for transactions conducted with point-of-sale 

systems or devices activated by debit cards, credit cards, and/or cash. The sales information 

recorded by cash registers when interfaced with a retail motor-fuel dispenser shall contain the 

following information for products delivered by the dispenser: 

(a) the total mass of the delivery, 

(b) the unit price, 

(c) the total computed price, and 

(d) the product identity by name, symbol, abbreviation, or code number. 

Change to Requirement: Modified 

Paragraph S.3.5. 

Requirement Title: Automatic 

Density Correction 

Reason for Change: 

Added text to explain 

composition as it relates to 

technology 

S.3.5. Automatic Density Correction.

An automatic means to determine and correct for changes in product density shall be incorporated 

in any hydrogen gas metering system where measurements are affected by changes in the density 

(e.g., the effects of temperature, pressure, or variations in composition due to the feedstock, 

processing, storage, or the environment) of the product being measured. 

Change to Requirement: Modified 

Paragraph S.3.6. and Paragraph Title 

Requirement Title: 

Pressurization of Discharge 

Hose 

Reason for Change: Changed 

the term “pressure” to 

“pressurization.” Added 

missing text to last sentence to 

clarify indications must not 
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advance during purging or 

bleeding of the discharge hose 

S.3.6. Pressurizing the Discharge Hose. - The discharge hose for hydrogen gas shall automatically 

pressurize to pressure equal to the receiving vessel prior to the device beginning to register the 

delivery. Initial hose pressurization shall not advance the indications. 

The discharge hose shall be repressurized at the beginning of a delivery when venting occurs at 

the end of the fueling operation. Purging/Bleeding of the discharge hose shall not advance the 

indications.

Change to Requirement: Modified 

Paragraph S.3.7.(c) 

Requirement Title: Zero SetBack Interlock, Retail MotorFuel Devices Reason for Change: 

Changed the term “pump” to 

“source” to recognize the 

difference in how hydrogen 

supply systems operate 

S.3.7. Zero-Set-Back Interlock, Retail Motor-Fuel Devices. - A device shall be constructed so that: 

(c) in a system with more than one dispenser supplied by a single pump source, an effective automatic control valve in each dispenser prevents product from being delivered until the indicating 

elements on that dispenser are in a correct zero position. 

Change to Requirement: Modified 

Paragraph S.5 (f) 

Requirement Title: Markings; 

Flow Rates 

Reason for Change: Deleted the 

term pound 

S.5. Markings. - A measuring system shall be conspicuously, legibly, and indelibly marked with the 

following information: 

(f) maximum and minimum flow rates in kilograms or pounds per unit of time; 

Change to Requirement: Modified 

Paragraph S.5.(h) 

Requirement Title: Markings; 

Applicable Range of 

Temperature 

Reason for Change: 

Clarified that the device must 

be marked with the ambient 

temperature range at which the 

system operates if it is other 

than 

10 °C to +50 °C 

S.5. Markings. - A measuring system shall be conspicuously, legibly, and indelibly marked with the 

following information: 

(h) applicable range of ambient temperature if other than -10 °C to +50 °C; 
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Change to Requirement: Added a new 

Note to Paragraph S.7. 

Requirement Title: Totalizers 

for Retail Motor-Fuel Devices 

Reason for Change: 

Clarified the purpose of a 

nonresettable totalizers by 

providing examples of how 

they are used. 

S.7. Totalizers for Retail Motor-Fuel Devices. - Retail motor-fuel dispensers shall be equipped with a 

nonresettable totalizer for the quantity delivered through each separate metering device. 

Note: Examples of possible uses that necessitate a nonresettable totalizer include, but are not limited 

to: (1) tracking product dispensed during test, (2) detecting diversion of product after it is metered, 

(3) detecting discrepancies between blend settings and posted octane values, (4) detecting use after the 

device is removed from service, and (5) collection of motor-fuel taxes.

Change to Requirement: Added a new 

Paragraph N.4.1 

Requirement Title: Transfer 

Standard Test 

Reason for Change: Added 

new text to recognize the 

transfer standard test method 

and an appropriate size for the 

test draft 

N.4. Tests 

N.4.1. Transfer Standard Test. - When comparing a meter with a calibrated transfer standard,

the test draft shall be equal to at least the amount delivered by the device in two minutes at its 

maximum discharge rate.

Change to Requirement: Added a new 

Paragraph N.4.2 

Requirement Title: 

Gravimetric Test 

Reason for Change: Added 

new text to recognize the 

gravimetric test method and an 

appropriate size for the test 

draft 

N.4. Tests 

N.4.2. Gravimetric Test. – The weight of the test drafts shall be equal to at least the amount 

delivered by the device in two minutes at its maximum discharge rate. 

Change to Requirement: Modified text 

in existing Paragraph N.5 

Requirement Title: Minimum 

Measured Quantity 

Reason for Change: 

Renumbered Paragraph from 

N.4 to N.5 and modified text to 

clarify that the flow rate at 

which a device must undergo 

performance test for delivery of 

the minimum measured 
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quantity. 

N.45. Minimum Measured Quantity. - The device shall be tested for a delivery equal to the declared 

minimum measured quantity when the device is likely to be used to make deliveries on the order of the 

declared minimum measured quantity. Any minimum measured quantity test shall be made at the 

minimum flow rate of the installation.

Change to Requirement: Modified 

Paragraph N.7 

Requirement Title: Density Reason for Change: Modified 

to reflect current and upcoming 

standards reference information 

available by mid summer 2008. 

See draft code. 

Change to Requirement: Added new 

Paragraph T.4.2. 

Requirement Title: Tolerance 

Applications; Transfer 

Standard 

Reason for Change: Added text 

to specify how tolerances are 

applied when verifying 

standards using the transfer 

standard test method 

T.4. Tolerance Application. 

T.4.2 To the basic tolerance values that would otherwise be applied, there shall be added an 

amount equal to two times the standard deviation of the applicable transfer standard when 

compared to a basic reference standard.

Change to Requirement: Modified 

Paragraph UR.1.3.(b) 

Requirement Title: Minimum 

Measured Quantity 

Reason for Change: Clarified 

that a manufacturer and weights 

and measures authority may 

specify minimum measured 

quantities for a device and 

performance requirements 

apply to either quantity when 

that minimum measured 

quantity is likely to be the 

delivery. 

UR.1.3. Minimum Measured Quantity. 

(b)The minimum measured quantity appropriate for a transaction may be specified by the weights and 

measures authority. A device may have a declared minimum measured quantity smaller than that 

specified by the weights and measures authority; however, the device must perform within 

performance requirements for the declared or specified minimum measured quantity up to deliveries 

at the maximum measurement range. 
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Change to Requirement: Modified 

Paragraph UR.2.2. 

Requirement Title: Discharge 

Rate 

Reason for Change: Added text 

to recognize that some system’s 

are designed to reach maximum 

flow rate only after initial 

equalization, then delivery 

occurs 

UR.2.2. Discharge Rate. - A device shall be installed so that after initial equalization the actual 

maximum discharge rate will not exceed the rated maximum discharge rate. Automatic means of flow 

regulation shall be incorporated in the installation if necessary. 

Change to Requirement: Modified 

Paragraph UR.3.8. 

Requirement Title: 

Conversion Factors 

Reason for Change: Deleted 

the term pound 

UR.3.98. Conversion Factors. – Established conversion values (see references in N.67) shall be used 

whenever metered hydrogen gas is billed. All sales shall be based on grams or kilograms or pounds. 

Change to Requirement: Added a new 

definition to Appendix D 

Definition Title: Minimum 

Measured Quantity 

Reason for Change: Clarified 

the special meaning of the term 

used in the code. 

minimum measured quantity (mmq). The smallest quantity delivered for which the measurement is 

accurate for that system.[3.37, 3.3X]

Change to Requirement: Added a new 

definition to Appendix D 

Definition Title: 

Nonresettable Totalizer 

Reason for Change: Clarified 

the special meaning of the term 

used in the code. 

nonresettable totalizer. An element interfaced with the measuring or weighing element that 

indicates the cumulative registration of the measured quantity with no means to return to 

zero.[3.30, 3.37, 3.3X]

(4) Next Steps/Tasks 

The DSTPS discussed ideas for how the work should progress to complete the work on equipment 

standards and the next phase of its work to develop corresponding test procedures. Project work was 

identified on the following subjects: 

Composition 

Various metering technologies may be used to deliver hydrogen where the affects of pressure, temperature, 

and composition may affect product density. The measurements made by some meter technologies may 

need to be corrected for changes in any factors that affect measurement accuracy so the device can meet 

performance requirements. 
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Test Procedures 

The DSTP requested that participants forward test data which demonstrates that the current 1.5% accuracy 

tolerance in the draft code is appropriate 

The DSTPS discussed work by the CDFA/DMS to develop a draft checklist of test criteria for the type 

evaluation of hydrogen dispensers. Equipment OEMs questioned if there is reciprocity in the 50 states for 

type evaluation test data. There are only limited agreements for reciprocity among the 50 States; however, 

most states participate in the NCWM National Type Evaluation Program. Since there is no nationally 

recognized hydrogen code, then a checklist would be based on ad hoc procedures derived from existing 

codes. Manufacturers were interested in the process whereby other jurisdictions might recognize the 

CDFA/DMS test results and permit the commercial use of hydrogen dispensers in their states. 

(5) Next Meeting 

At the conclusion of the March 5 meeting the DSTPS discussed possible locations for a May/June 2008 

meeting. The three sites suggested were the Gas Technology Institute (Des Plaines, IL), Air Products and 

Chemicals, Inc. (Allentown, PA) and the southern California site of an upcoming meeting for the fuel cell 

industry. The USNWG will correspond by email to determine the location of the next meeting. Future 

meeting locations will be based on logistics and technical tasks that the USNWG must accomplish. 

The DSTPS agreed that invitations should be extended to automobile manufacturers and energy providers 

for their input and participation in anticipation of their resistance to requirements for specific fueling 

protocols. 

(6) USNWG - Technology Tours 

On March 5, 2008, the USNWG had the opportunity to participate in a Ride and Drive Tour of hydrogen 

fuel cell vehicles at the California Fuel Cell Partnership (CaFCP) in West Sacramento and tour the 

hydrogen refueling system at the Sacramento Municipal Utilities District (SMUD) in Sacramento. The 

USNWG was able to observe the latest hydrogen transportation and refueling technology. The USNWG 

wishes to express its deepest appreciation to the CaFCP, SMUD, and Air Products and Chemicals, Inc. for 

this learning experience. 

FUEL SPECIFICATIONS SUBCOMMITTEE (FSS) MEETING 

Thursday March 6, 2008, 8:30 a.m. – 12 noon (PT) 

California Fuel Cell Partnership, 3300 Industrial Blvd., Dr. Lloyd Conference Room 

West Sacramento, CA 95691 

Moderator – Kenneth Butcher (NIST WMD) 

(1) Welcome and Introductions 

The FSS was welcomed, the meeting called to order, and the FSS objectives were covered. The 

collaborative work by the meeting's sponsors, DOE and NIST was recognized. Participants were briefed on 

the facilities available at the CaFCP, the schedule of events, meeting administrative procedures, and 

materials. Participants were invited to provide their name, affiliation, and state their specific area of interest 

in the work to develop a hydrogen fuel specification. 

Due to the time constraints of the meeting the administrative tasks of nominating a Chair and distribution of 

the USNWG guidelines were covered in this session. The FSS did not have any nominations for Chair of 

the FSS at this time. The FSS was encouraged to agree on candidate(s) by the next meeting. The 

appointment of a Chair is important given the size of the task before the FSS to ensure and promote the 

development of appropriate and fair: (1) method of sale requirements, (2) labeling requirements, (3) fuel 
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quality standards, (4) sampling procedures, (5) field and laboratory inspection procedures, test equipment 

standards, and safety practices, and (7) training for officials and laboratories in support of the hydrogen 

economy. 

The FSS was asked to review and comments on the draft USNWG Guidelines from the DSTPS by March 

25, 2008. The guidelines describe the work group and its subcommittee’s objectives, general membership, 

meeting and voting procedures, and timelines for projects and other tasks. The FSS will be balloted 

electronically for their comments and approval of the guidelines. 

 

(2) Background and History 

Typically, motor-fuel quality standards are developed by standards bodies other than those working directly 

with the weights and measures community. The weights and measures community may have members 

participating in the work of those Standards and Code Developing Organizations. The USNWG will not 

change that process nor develop the fuel quality standard, but will eventually recommend quality and other 

related weights and measures laws (definitions, specifications, and method of sale) that should be included 

in NIST Handbook 130. NIST Handbook 130 is a compilation of the latest uniform standards, related 

interpretations, and guidelines in the areas of legal metrology and engine fuel quality. States may choose to 

adopt Handbook 130 as law and regulation. States then establish and administer programs that monitor and 

enforce method of sale and fuel specification laws. 

Work is under way within the global hydrogen community to establish fuel specifications, sampling 

procedures, and identify test equipment to determine acceptable levels of purity and contaminants, other 

elements, and particulates for hydrogen refueling applications. The FSS discussed the status of ongoing 

work to address hydrogen fuel specifications by the International Organization for Standardization (ISO) 

Technical Committee 197 Working Group 12, California Department of Food and Agriculture Division of 

Measurement Standards (DMS) (see Appendix H), and the Technical Information Report developed under 

the SAE Standard J2719. Research is ongoing to determine if it is feasible for products to meet projected 

specifications and to ascertain if laboratories are capable of making measurements to proposed standards. 

The FSS is interested in data analysis on contaminant sources such as the environment, motor-fuel 

dispensing system, sampling methods/equipment, and/or feedstock. 

In its October 2007 meeting, the USNWG recommended an approach that set the limits for hydrogen fuel 

purity on a percentage basis. The USNWG discussed the allowable limits for hydrogen purity and its 

affects on the accuracy of refueling equipment when measurements are influenced by a product's molecular 

weight. The FSS is in agreement with the USNWG's earlier decision that impurities up to 0.03 % would 

not have a significant affect on measurement accuracy. 
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(3) Method of Sale for Hydrogen Dispensing Applications 

The FSS was asked to consider proposals developed by NIST to amend NIST Handbook 130 to recognize 

hydrogen refueling applications to address the method of sale, define what products fall under this 

application, and device labeling for hydrogen dispensers. The FSS also agreed that unit pricing in decimal 

cents should be prohibited since this practice did not represent a better value. 

The FSS agreed with the October 2007 decision of the USNWG to meter hydrogen in mass units of the 

kilogram which has an energy value similar to that of a gallon of gasoline. Consequently, the kilogram 

becomes acceptable from a metrological and consumer standpoint. 

The first proposal would modify NIST Handbook 130 Section IV. Uniform Regulations Part B. Uniform 

Regulations for the Method of Sale of Commodities Section 2 Non-food Products. The proposal would 

include a definition for "hydrogen fuel" that is taken from language developed by the California Division of 

Measurement Standards. The proposed language is worded similarly to current NIST Handbook 130 text 

which addresses corresponding requirements for compressed natural gas dispensers and reads as follows: 

2.XX. Retail Sales of Hydrogen Fuel.

2.XX.1. Definition.

2.XX.1.1. Hydrogen Fuel. - Means a fuel composed of the chemical hydrogen intended for 

consumption in an internal combustion engine or fuel cell. 

2.XX.2. Method of Retail Sale and Dispenser Labeling.

2.XX.2.1. Method of Retail Sale. - All hydrogen fuel kept, offered, or exposed for sale and 

sold at retail shall be in terms of the kilogram. 

2.XX.2.2. Dispenser Labeling. - All retail hydrogen fuel dispensers shall display the unit 

price in terms of price per kilogram. 

2.XX.2.3. Street Sign Prices and Advertisements. – When the unit price of hydrogen fuel 

is shown on street signs and or in any advertisement it shall be in terms of price per 

kilogram (e.g., “$3.49 per kg”. 

When signage is available there should be agreement on the prices displayed on the dispenser and sign. 

Additionally any condition of sale, which result in a difference in prices for the same product, should also 

be part of the advertisement. 

Although a definition for hydrogen fuel is proposed for the method of sale requirements a corresponding 

definitions is also proposed for NIST Handbook 130 Section IV. Uniform Regulations Part G. Uniform 

Engine Fuels, Petroleum Products, and Automotive Lubricants Regulations Section 1. Definitions to read as 

follows: 

 

1.XX. Hydrogen fuel means a fuel composed of the chemical hydrogen intended for consumption in 

an internal combustion engine or fuel cell. 

At the conclusion of its March 2008 Meeting, the FSS agreed that the conditions for sale should be stated 

with the associated price in whole cents/kilogram in street signage and dispenser labeling. The draft text 
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will be revised to include the recommended and other editorial changes and distributed for the FSS’s review 

and input. 

(4) Engine Fuel Quality 

The FSS discussed the many similarities between the fuel specification draft standards and reports issued by 

the CDFA/DMS, ISO, and SAE and reviewed draft proposals for model fuel quality guidelines for NIST 

Handbook 130. The FSS discussed the effects on hydrogen fuel composition when impurities and 

particulates reach the maximum allowable levels listed in the CDFA/DMS draft quality standard. The FSS 

agreed to consider the CDFA/DMS standard as a starting point for a fuel quality specifications for 

hydrogen. The FSS was in agreement on the maximum allowable levels of helium, nitrogen, argon, 

oxygen, total gases and hydrocarbons, and water. Questions were raised about the capability of today's 

equipment to detect even the maximum allowable levels of ammonia, carbon dioxide, carbon monoxide, 

formaldehyde, formic acid, particulates, and total halogenated and sulfur compounds in the draft standard. 

The FSS would like to see what research will yield on the best approach to detect and determine these 

contaminants. The FSS is interested in what that data reveals about the full relevance of these contaminants 

at these levels on technology and properties of hydrogen. The FSS also has questions about the start of 

round robins, readiness of laboratory instrumentation, and the availability of standard reference materials. 

The CDFA/DMS standard was about to complete its public review cycle. CDFA/DMS indicated the 

March 3, 2008 draft is an interim standard until an ANSI recognized body publishes some other quality 

standard. Once a hydrogen fuel quality standard is adopted it will be cited in NIST Handbook 130 Section 

IV. Uniform Regulations Part G. Uniform Engine Fuels, Petroleum Products, and Automotive Lubricants 

Regulations Section 2. Standard Fuel Specifications. Section 3. Classification and Method of Sale of 

Petroleum Products may need to be amended to recognize nonpetroleum products and specify allowable 

terms and abbreviations for identifying hydrogen fuel and the pressures for dispenser applications. 

(5) Accurate Measurement of Water Vapor Concentration 

Accurate measurement of water vapor concentration directly relates to the determination of hydrogen fuel 

purity on a percentage basis and hydrogen fuel density. Water vapor is considered one of the most 

significant contaminants included in the hydrogen fuel specification. In the current ISO TC197 standard 

and SAE J2719 report, it is specified as 5 PPM by volume. This water vapor concentration corresponds to a 

frost-point of -65.6 °C at one atmospheric pressure with a hydrogen gas density of 0.00531 grams per cubic 

meter in which the density of water vapor is 0.00520 grams per meter and the density of hydrogen is 

0.00011 grams per cubic meter. Therefore, the FSS was asked to carefully consider the use of hydrogen fuel 

density in metering. 

This topic involves the expanded uncertainty (k=2) in water vapor concentration for hydrogen fuel 

specifications, which is proportional to the square root of the sum of relative standard uncertainties of the 

enhancement factor, the total pressure, and the saturation water vapor pressure. The uncertainty in the 

enhancement factor is directly proportional to the uncertainty in the second virial coefficient for water, with 

hydrogen representing the interaction between water molecules and hydrogen molecules. A high accuracy 

second virial coefficient for hydrogen-water mixture has recently become available (see Peter Huang, 

“Thermodynamic Properties of Hydrogen-Water Vapor and Air-Water Vapor Mixture in Fuel Cells,” ECS 

Trans. 5, (1) 613 (2007)). 

(6) Laboratory Manual 

The FSS did not have the opportunity to discuss the ongoing work to ensure fuel quality laboratories 

perform measurements that are traceable to recognized national standards. The FSS will need to consider 

the best approach to promote the establishment of documented laboratory practices and procedures that 

encompass: 
USNWG COMMERCIAL H2 MEASMT STANDARDS 

2008 MAR MTG SUMMARY 

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(a) Test Methods and Reproducibility Limits 

(b) Equipment (minimum and recommended) Source and Cost 

(c) Documentation (e.g., Standard Operating Procedures) 

(d) Handling and Storage of Hydrogen Fuel 

(e) References and Good Laboratory Practices 

(f) Minimum Training Standards for Laboratory Personnel 

(g) Facilities 

(h) Safety 

(7) Field Sampling Procedures

The USNWG anticipates there are two separate tests that will need to be performed by weights and 

measures/fuel quality officials. The first is an accuracy test of the dispenser system and the second is 

sampling hydrogen delivered at high pressures for compliance with quality specifications. The FSS 

considered the capability of existing sampling equipment and learned firsthand about a first generation 

sampling device now in the possession of CDFA/DMS. The FSS will be asked to consider field sampling 

methods and equipment that ensure uniform inspection, sampling, and enforcement procedures to promote 

and ensure the protection of consumers (vehicles) and businesses from economic loss resulting from 

substandard product and to encourage safe practices by officials conducting inspections. The initial 

recommendations are for developing procedures/guidelines that address: 

(a) Equipment/Source/Cost 

(b) Good Sampling Practice 

 

(c) Handling, storage, and transportation 

(d) Minimum Training Standards for Field Officials 

(8) Next Steps

The FSS agreed that the technology in use to determine fuel quality is an emerging one and must be 

monitored closely to stay current with the latest and most appropriate method and equipment for analysis. 

The FSS will continue researching the status of this work as it considers how future work should progress 

and before it modifies existing recommendations or develops new proposals. 

 

(9) Next Meeting 

Three sites suggested were the Gas Technology Institute (Des Plaines, IL), Air Products and Chemicals, 

Inc. (Allentown, PA) and the southern California site of an upcoming meeting for the fuel cell industry. 

Future meeting locations will be based on logistics and the technical needs outlined by the FFS. 

The FSS, like the DSTPS, agreed that invitations should be extended to automobile manufacturers and 

energy providers for their input and participation in anticipation of their resistance to requirements for 

specific uniform pricing units and fueling protocols.
USNWG COMMERCIAL H2 MEASMT STDS 

2008 MAR MTG DRAFT SUMMARY 

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Appendix M 

Attendee List 

USNWG Hydrogen Device Standards and Test Procedures and Fuel Specifications Subcommit

Name Agency Phone Email Device 

Standards 

and Test 

Procedures 

Subcommitee 

Member 

Yes (Y) 

Fuel 

Specifications Subcommittee 

Member 

Yes (Y) 

Atte

De

Stan

and 

Proc

S

com

Me

Ye

Jacquelyn Birdsall 

California Fuel Cell Partnership 

916-375-7421 jbirdall@cafcp.org Y Y 

Robert Boyd 

Hydrogen Solutions – Linde Group 

510-786-5903 bob.boyd@linde.com Y Y Y 

Kenneth Butcher 

NIST-TS WMD 

301-975-4859 kenneth.butcher@nist.gov Y Y 

Tina Butcher 

NIST – TS WMD 

301-975-2196 tina.butcher@nist.gov Y Y 

Marc Buttler 

Micro Motion/Emerson Process Management 

303-530-8562 marc.buttler@emersonprocess.com Y Y Y 

Joseph Cohen 

Air Products and Chemicals, Inc. 

610-481-7625 cohenjp@airproducts.com Y Y Y 

Jared Hightower 

Greefield 972-889-2400 

Ext. 129 

Jared.Hightower@us.atlascopco.com Y Y Y 

Robert Ingram 

CA – Food and Agriculture, Division of Measurement Standards 

916-229-3016 ningram@cdfa.ca.gov Y Y Y 

Michael Endress & 303-823-5796 michael.keilty@us.endress.com Y Y Y 
USNWG COMMERCIAL H2 MEASMT STDS 

2008 MAR MTG DRAFT SUMMARY 

Page 16 of 19 

Keilty Hauser Flowtec 

AG 

Kristin Macey 

CA – Food and Agriculture, Division of Measurement Standards 

916-229-3044 kmacey@cdfa.ca.gov Y Y Y 

Jonathan Munetz 

Sentech, Inc. 202-586-6644 jonathan.munetz@ee.doe.gov Y Y Y 

G. Diane Lee 

NIST – TS WMD 

301-975-4405 diane.lee@nist.gov Y Y Y 

David Pearce 

Greenfield Compression 

972-889-2400 Ext. 134 

dave.pearce@us.atlascopco.com 

Kenneth Ramsburg 

MD Dept of Agriculture, Weights and Measures Program 

410-841-5790 ramsburk@mda.state.md.us Y Y Y 

Ralph Richter 

NIST – TS WMD 

301-975-3997 ralph.richter.@nist.gov Y Y Y 

Antonio Ruiz 

DOE 202-586-0729 Y Y Y 

James Scott 

Praxair, Inc. 716-879-2596 jim_scott@praxair.com 

Michael Steinbach 

Instrutech, Inc. 303-651-0551 

Ext. 110 

mikes@instrutechinc.com Y Y Y 

Kevin Sterling 

Florida Dept. Of Agriculture, Division of Standards 

850-487-2634 sterlik@doacs.state.fl.us Y Y 

Curt Williams 

Georgia Dept. Of Agriculture 

404-363-7597 cwilliam@agr.state.ga.us Y Y 

Juana Williams 

NIST – TS WMD 

301-975-3989 juana.williams@nist.gov Y Y Y 

John NIST Chemical 301-975-5937 john.wright@nist.gov Y Y 
USNWG COMMERCIAL H2 MEASMT STDS 

2008 MAR MTG DRAFT SUMMARY 

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Wright Science and 

Technology Laboratory, Process Measurements Division 

David Wyatt 

Wyatt Engineering 

401-334-1170 dwyatt@wyattflow.com Y Y 

Guests 

Name Agency Phone Email Device 

Standards and 

Test 

Procedures 

Subcommittee 

Member 

Yes (Y)

Fuel 

Specifications 

Subcommittee 

Member 

Yes (Y)

Attend

Devic

Standard

Test 

Proced

Subcomm

Meeti

Yes (Y

Gerhard Achtelik 

CA Air Resources Board 

gachteli@arb.ca.gov 

Nico Bouwkamp 

California Fuel Cell Partnership

nbouwkamp@cafcp.org Y 

Rob Burgess Hydrogen 

Technologies and Systems National Renewable Energy Laboratory 

 robert_burgess@nrel.gov

Gary Castro CA Dept. of gcastro@cdfa.ca.gov 
USNWG COMMERCIAL H2 MEASMT STDS 

2008 MAR MTG DRAFT SUMMARY 

Page 18 of 19 

Food and Agriculture Div. of Measurement Standards 

Ben Deal CA Air 

Resources Board 

 

Al Hebert CA Dept. of 

Food and Agriculture Div. of Measurement Standards 

 ahebert@cdfa.ca.gov Y 

Peter Huang NIST 

Chemical Science and Technology Laboratory, 

 Peter.huang@nist.gov Y 

Steve Huffman 

Air Products and Chemicals, Inc. 

 

Dr. Hsu John Mough CA Dept. of 

Food and Agriculture Div. of Measurement Standards 

 Y 

Charles Nelson 

CA Dept. of Food and Agriculture Div. of Measurement 

 Y 
USNWG COMMERCIAL H2 MEASMT STDS 

2008 MAR MTG DRAFT SUMMARY 

Page 19 of 19 

Standards 

Van Thompson 

CA Dept. of Food and Agriculture Div. of Measurement Standards 

916-229-3025 

vthompson@cdfa.ca.gov Y