Hydrogen leak detection systems may be required by the Authority Having Jurisdiction (AHJ) or may be installed as a means for enhancing safety. Leak detection can be achieved by providing hydrogen (or flammable gas) detectors in a room or enclosure, or by monitoring the internal piping pressures and/or flow rates for changes that would suggest a leak is present in the system. Other methods include providing detectors in close proximity to the exterior... Read More

Hydrogen is unlike conventional fuels such as gasoline or propane, which are heavier than air and tend to accumulate at ground level. Hydrogen is lighter than air and will accumulate near the ceiling or roof area, or in pockets at these locations. When the buoyancy of hydrogen is not properly taken into account in the design of facilities, hydrogen leaks can become more dangerous than leaks or spills of conventional fuels. As a result... Read More

Extensive industrial experience has shown that hydrogen degrades the mechanical properties of structural metals under certain conditions through a process called "hydrogen embrittlement", enabling the initiation and propagation of cracks. Degraded structural integrity of components, piping, and other equipment containing hydrogen is a critical safety issue, since such failures can lead to the unintended release of hydrogen gas.

Pressure relief is an essential element of both gaseous and liquid hydrogen storage systems to guard against excessive pressure that could result in catastrophic failure of the system. A burst disk (or rupture disk) is a common pressure-relief device that is designed to break at a predetermined pressure. It is a one-time-use device that is either destroyed or permanently deformed in response to over pressurization and then must be replaced. A burst disk is sometimes used as a backup... Read More

Batteries are used in a wide variety of vehicle and stationary applications. Large industrial facilities (e.g., warehouses) have designated battery charging areas, most of which require adequate ventilation to exhaust the hydrogen gas that is released during charging. The facility size and the number of chargers in operation simultaneously determine whether natural-draft ventilation is adequate or if forced-draft ventilation... Read More

The H2Incidents database contains three incidents in which excess hydrogen was unintentionally introduced into an anaerobic chamber in a laboratory setting. The combination of hydrogen, air, and an ignition source proved to be extremely hazardous; two of the incidents resulted in explosions, and the third came very close to an explosion. The incidents were all caused by human error, which highlights the importance of... Read More

One should always assume that hydrogen is present and verify that the system has been purged to the appropriate level when performing maintenance on a hydrogen system. Maintenance activities that could lead to a release of hydrogen should not be initiated until the hydrogen has been purged from the system. (NOTE: In most cases, this is done by procedure, not by analysis. For piping, the approach is generally not an issue, but for large vessels, analysis is the... Read More

International scientists and engineers are working with reactive metal-hydride hydrogen storage materials in their laboratories. Activities ranging from new materials discovery, to properties characterization, and engineered system development are being performed to develop safe and economically favorable on-board and off-board storage for hydrogen-powered vehicles and stationary applications of the future. The materials must... Read More

Management of change (MOC) is the process used to review all proposed changes to equipment, procedures, materials, personnel, and process operations before they are implemented to determine their effects on safety vulnerabilities. For example, standard operating procedures generally describe the acceptable operating ranges of process parameters (e.g., flow rates, concentrations, pH ranges, temperatures, pressures). A knowledgeable person should evaluate any proposed parameter changes... Read More