Codes and standards to address issues like this one are under development, along with applied research and field trials. As with any new application, appropriate codes and standards must be developed to meet public risk targets.

Systems should be sited in accordance with national and local standards such as NFPA 2, Hydrogen
Technologies Code. The nature of a trailer filling operation is not much different than a vehicle fueling
station, so the hazards are comparable and similar safeguards such as walls and sensors will apply. These
facilities might be larger and industrial standards and regulations will also…

Exposure between these products is bidirectional. A hazard analysis should consider what happens to
alternate fueling equipment if an incident with one of the fuels occurs. Care must be taken to have the
appropriate separation distance and mitigations according to the applicable codes. Limited experience
with existing stations has shown that these multi-fuel stations can be successful…

Researchers from Sandia National Laboratories have conducted extensive research on these topics. They have reviewed the current literature, identified knowledge gaps in alternate fuel vehicles and tunnel safety, and developed a generalizable framework to assess tunnel safety for a diverse range of alternate fuel vehicles. Supported by…

The Hydrogen Safety Panel is not aware of any detailed guidelines or requirements. There are general requirements for personal protective equipment (PPE) in relevant codes and standards, but these often defer to the manufacturers requirements or a material safety data sheet (MSDS) for specifics. Ultimately, PPE selection is a matter between the employer and the employee and may need to…

Previous versions of NFPA 55 listed overhead power lines within the separation distance tables with no voltage distinction. The separation distances were 15 ft for GH2 and 25 ft for LH2 for all overhead electrical lines. The current edition of NFPA 2 includes these in overhead utilities; the distance for GH2 and LH2 will vary with pressure and diameter of the hydrogen piping. In practice, high…

The Global Asset Protection Services (GAPS) standard was written 20 years ago for property loss prevention at crowded chemical plants and is intended for existing and new oil and chemical facilities to limit explosion over-pressure and fire exposure damage; thus, the purpose is different than NFPA 2. NFPA distances were based on studies from the 1960s as well as qualitative factors that were…

There is technically no upper limit for GH2 storage listed within the separation distance tables within Chapter 7 of NFPA 2. For LH2, there is a 75000-gallon upper limit for the LH2 storage separation distance tables within Chapter 8 for LH2. 
It’s important to note that many facilities have site specific issues such as large quantities, confinement, and congestion, so it may be…

These distances are based primarily on hydrogen piping releases and resultant vapor clouds and jet flames based on pipe diameter and pressure. It’s important to note that many facilities have issues such as confinement and congestion, so it may be applicable to apply contemporary engineering models to assess risk.

Hydrogen gas storage and fuel cell systems are typically closed systems with a variety of monitoring and control functions to prevent leaks. Please check with the bus manufacturer and authority having jurisdiction to verify this is acceptable per their direction. However, a good safety practice would be to minimize the time spent indoors for these activities. Hydrogen vehicles maintained in a…