Safety Considerations in Designing a Facility for Mechanical Property Measurements in High Pressure Gaseous Hydrogen Environments
A.J. Slifka, Y.S. Levy, N.E. Nanninga, T.A. Siewert, and J.D. McColskey NIST, Materials Reliability Division

NIST has constructed a new facility focused on fatigue measurements of pipeline steels in high-pressure hydrogen gas. The system is capable of pressures up to 140 MPa (20,000 psi), although most measurements will be made at or below 34 MPa (5000 psi). Measurements are planned for steels ranging from X52 to X100, where the API 5L designation specifies the minimum yield strength of the steel in units of ksi. Current codes for transportation of gaseous hydrogen such as ASME B31.12 justifiably lean toward safety. The required wall thickness of a given type of pipeline steel at a given maximum pressure is conservatively high, making it expensive to install new pipelines for hydrogen transport. An option would be to re-purpose old or existing natural gas pipeline. In either case, a reliable body of data on fatigue of pipeline steels in high-pressure gaseous hydrogen as well as lifetime models are needed. With these, codes can be redefined, perhaps relaxing them while maintaining safety, and parameters for re-purposing can be identified.

When bringing a new research facility online, NIST scrutinizes all associated safety issues. NIST uses an internal hazard review of the new facility or experiment, where codes and standards are drawn upon to define safe design and operation. The internal review for the hydrogen testing facility was very valuable, because it had many eyes looking at the safety issues, and the people on the review committee came from diverse technical backgrounds. This variety of backgrounds produced different viewpoints and focused on many different safety areas so that the chance of something being overlooked was remote. In addition, NIST has an Office of Safety, Health and Environment, with a representative from this office on the Hazard Review Committee. However, nobody on the Hazard Review Committee had significant experience with hydrogen, so the initial reaction of the review committee was that measurements in high-pressure hydrogen were highly perilous. Yet as each separate issue was addressed and codes were cited for each major part—such as building, ventilation, fuel gas, pressure vessel, sensors, and electronics—everyone came to an agreement that hydrogen can be safely used, even at high pressures. All were educated in the fact that although hydrogen has a small ignition energy, its light weight and high diffusivity make it a lower overall hazard than commonly-used fuels such as gasoline and acetylene. We invited our onsite police and the local fire department to tour the facilities, we answered questions about their concerns, and, in turn, received information from them on how they would respond to an alarm. We hired third-party safety experts, and also invited the Hazard Review Committee, the police, and the fire department to attend a laboratory walkthrough with these safety experts.

The design for safe operation of the facility uses multiple levels of engineering controls. The first level is our ventilation system, which yields seven air changes per hour with 100 % outside air, twice as many as required by code (ASHRAE 62.1) based on the size of the building. The second level is the gas capacity of our measurement system, which is small compared to the size of our building. The building has a volume of 350 m3 at NTP (normal temperature and pressure), whereas at maximum pressure the test vessel contains 2.5 m3 of hydrogen at NTP. At uniform concentration, if all of the hydrogen leaked out of the vessel, there would still not be a combustible mixture of hydrogen and air in the building. However, hydrogen rises, so there could be a flammable mixture near the ceiling in the event of a catastrophic leak. The third level of safety is that all of the electronics in the upper half of the building are explosion proof, so there are no spark sources where the hydrogen would naturally accumulate. In fact, most of the electronics in the laboratory are either explosion proof or intrinsically safe. The load frames are not available with such electronics, so the solenoid valves and load cells are the only potential spark sources from the electronics in the laboratory. However, the solenoid valves are located to the side of the gas supply plumbing and the test vessel, and the load cells run such small power that they could qualify as intrinsically safe. The fourth level of safety is the use of multiple hydrogen sensors that are interlocked to the gas supply. We have five hydrogen sensors, of which four are catalytic-bead type and one is a thin-film type. Of the four bead-type sensors, two are mounted directly above each of the load frames at ceiling level, and the other two are mounted above the wall of plumbing components and also directly above each of the hydrogen compressors and are also at ceiling level. The single thin-film sensor is mounted at ceiling level between the two load frames. The final level of safety is the fail-safe design of the gas supply system. The supply system is controlled with normally-closed, air-operated valves. Therefore, if either electrical power or compressed air fails, the gas supply system shuts off. There are also manual valves in the system to shut off the gas supply and to isolate major pieces of equipment, such as the gas compressors. There are sensors on both the air-operated and manual valves so that the automatic procedure can verify whether valves are open or closed.

International Standards – ISO/TC 197 (Hydrogen Technologies) Published Documents
Karen Hall, National Hydrogen Association

As several international working groups are meeting in September, we anticipate providing detailed activity reports over the next couple of months on working groups 8, 11, and 14. This month, we thought it would be appropriate to provide a current list of published documents from this very active international technical committee.

(Cor. = corrigendum; TS = Technical Specification; PAS = Publicly Available Specification; TR = Technical Report)

  • ISO 13984:1999 Liquid hydrogen—Land vehicle fuelling system interface

  • ISO 13985:2006 Liquid hydrogen — Land vehicle fuel tanks

  • ISO 14687-1:1999/ Cor. 1:2001/Cor. 2:2008: Hydrogen fuel — Product specification —Part 1: All applications except proton exchange membrane (PEM) fuel cells for road vehicles

  • ISO/TS 14687-2:2008 Hydrogen Fuel — Product Specification — Part 2: Proton exchange membrane (PEM) fuel cell applications for road vehicles

  • ISO/PAS 15594:2004 Airport hydrogen fuelling facility

  • ISO/TS 15869:2009 Gaseous hydrogen and hydrogen blends —Land vehicle fuel tanks

  • ISO/TR 15916: 2004 Basic considerations for the safety of hydrogen systems

  • ISO 16110-1:2007 Hydrogen generators using fuel processing technologies — Part 1: Safety

  • ISO 16110-2 Hydrogen generators using fuel processing technologies — Part 2: Test methods for performance

  • ISO 16111:2008 Transportable gas storage devices — Hydrogen absorbed in reversible metal hydrides

  • ISO 17268:2006 Compressed hydrogen surface vehicle refuelling connection devices (coordinated with SAE J2600)

  • ISO/TS 20100:2008 Gaseous hydrogen — Fuelling stations

  • ISO 22734-1:2008 Hydrogen generators using water electrolysis process — Part 1: Industrial and commercial applications

  • ISO 26142: 2010 Hydrogen Detection Apparatus – Stationary Applications

South Carolina Now First State to Uniformly Permit Hydrogen and Fuel Cells
Shannon Baxter-Clemmons, Ph.D., South Carolina Hydrogen and Fuel Cell Alliance

Beginning now, SC is the first state to uniformly permit hydrogen and fuel cells at the state level while using internationally recognized codes and standards.

The South Carolina Hydrogen Permitting Act (Bill H3835) was passed into law June 14, 2010. The new law places the authority and responsibility of permitting hydrogen and fuel cell facilities in SC in the jurisdiction of the Office of the State Fire Marshal. "The South Carolina Hydrogen Permitting Act is one small step on the road to clean, secure energy independence for the state and nation," said Shannon-Baxter Clemmons, executive director of the South Carolina Hydrogen and Fuel Cell Alliance.

About The Law
The US Department of Energy recently identified coding, standardization and permitting of hydrogen and fuel cells as a significant barrier to success for the industry. As a result, a collaborative effort between industry and government organizations assessed how South Carolina could implement a uniform permitting process that didn't cost the taxpayers of the state. The effort included participation from The Office of the State Fire Marshal, South Carolina Energy Office, SC Municipal Association, Dantherm Power, Engenuity, University of South Carolina, Greenway Energy, Center for Hydrogen Research, Savannah River National Laboratory, SCRA, South Carolina State University, Clemson University, US Department of Energy and South Carolina Hydrogen and Fuel Cell Alliance. The law allows the local Authorities Having Jurisdiction to become acquainted with hydrogen and fuel cell technologies. It also provides a reliable source of expertise at the Office of the State Fire Marshal without incurring onerous training expenses while the industry is in a build up phase. It also ensures that commercial and industrial businesses seeking to site hydrogen for energy use, or as a transportation fuel, are given equal treatment and are held to a consistent standard. 

Impact of the Law
The Hydrogen Permitting Act will help South Carolina increase economic development and job growth within the state. It will ensure that new ventures in hydrogen and fuel cells will be able to develop in a timely manner.

House Speaker Bobby Harrell said, "We are already seeing real-world private sector applications of hydrogen technology right here in South Carolina. As this new industry grows, we need to make sure our laws keep up with the progress of the market to prevent bureaucratic roadblocks. The Hydrogen Permitting Act helps pave the way for future private sector innovation and job creation by standardizing these fueling stations as the new gas stations of the 21st Century."

Brian Weeks, associate director at Advanced Energy Systems Gas Institute, echoed these sentiments.

"Establishing a statewide expert for hydrogen and fuel cell permitting will help remove uncertainty in the permitting of new, clean energy projects. This should benefit both project developers and consumers," said Weeks.

Public safety will also be a benefit of the new law. Citizens will be able to gain access to the technology through balanced and uniform safety precautions.

Ernest Chaput, director of special projects at the Center For Hydrogen Research, said, "South Carolina is once again leading the country in facilitating the adoption of hydrogen and fuel cells into our daily lives. By creating a uniform statewide permitting process, we have eliminated a major uncertainty for adopters of these important energy technologies while assuring public safety. This is a win-win for all."

Lastly, the law will greatly assist in the commercialization of hydrogen while also helping communities recognize hydrogen as a transportation fuel.

"South Carolina has made a significant statement about the emerging hydrogen economy with the passage of the SC Hydrogen Permitting Act. The legislation recognizes that hydrogen is transitioning from historic utilization as a specialized industrial gas to a more widespread energy source for the rapidly developing fuel cell industry in the state. This is sure to have a positive influence locally and nationally, because this law assures that the commercial appeal of hydrogen fuel cell systems will be accompanied by cost effective application standards that safeguard public health, safety, and provide education and awareness," said Sam Logan, CEO and president of LOGAN Energy.

Additional Support
In addition to the support of industry and government, the law also garnered key support from the Municipal Association of South Carolina (MASC).

"Cities and towns across our state are seeking out new and innovative ways to bring jobs and economic growth to their residents. Anything that helps our cities and towns add new technologies like hydrogen and fuel cells to local economic growth efforts is a very positive step," said Reba H. Campbell, deputy executive director of the MASC.

About the South Carolina Hydrogen and Fuel Cell Alliance
The South Carolina Hydrogen and Fuel Cell Alliance is a public-private collaboration for cooperative and coordinated utilization of resources in the state used to advance the commercialization of hydrogen and fuel cell technologies.

About Advanced Energy Systems Gas Institute
GTI is a not-for-profit Research and Development (R&D) organization. For more than 65 years, they have been the leader in the development and deployment of technology solutions that contribute to a secure, abundant, and affordable energy future. To date, GTI programs have resulted in nearly 500 products, 750 licenses, and more than 1,200 associated patents.

About Center For Hydrogen Research
The Center for Hydrogen Research is a collaboration between Savannah River National Laboratory (SRNL) and Aiken County. Located on the Savannah River Research Campus in Aiken County, South Carolina, their facility houses lab space for both the SRNL researchers and private partners to investigate and test the storage, production and supporting disciplines of hydrogen. The Center for Hydrogen Research is a member of the South Carolina Hydrogen and Fuel Cell Alliance and the National Hydrogen Association.

About LOGAN Energy
LOGAN Energy Corp. ("LEC") is a recognized world leader providing fuel cell solutions that target customer desires for clean energy services. The company has achieved technical proficiency through operating all commercial stationary fuel products, aggregating more than 10 megawatts of capacity. These installations include residential, commercial and industrial applications.

About MASC
The Municipal Association of South Carolina represents and serves the state's 270 incorporated municipalities. The Association is dedicated to the principle of its founding members: to offer the services, programs and tools that will give municipal officials the knowledge, experience and tools for enabling the most efficient and effective operation of their municipalities in the complex world of municipal government.