(119d) Safely Implementing Hydrogen to Your Facility

Hydrogen is a very powerful and useful element with properties that can be applied in a vast number of applications. When used safely, there are many benefits. Historically, after the Hindenburg incident, the use of hydrogen has been avoided for fear of its “explosive” properties. However, if the appropriate precautions are taken, hydrogen is a fascinating and powerful element with various benefits. While hydrogen in its nature demands respect and caution, there’s no need to fear hydrogen if the appropriate safety measures are taken.

In the last several years, the push for developing sustainable energy sources and the decarbonization of the atmosphere has been becoming the focal point of several industries. As a result, there has been a great deal of resources devoted to developing emerging hydrogen technologies such as fuel cell power systems, dual-fuel furnaces, electrolyzers and other hydrogen generators, hydrogen fueling/filling stations, etc.

With the increased focus on hydrogen in a world that is heading toward sustainability, there has been an increasing need in industry to learn about the safety requirements surrounding the implementation of hydrogen systems in existing or new facilities so that the governing codes, standards and best practices are applied. Some of these codes have undergone significant re-writes and expansion as a result of these emerging technologies.

Required codes and standards pertaining to hydrogen from the International Building Code (IBC), the International Fire Code (IFC), the National Fire Protection Agency (NFPA), the Compressed Gas Association (CGA) and the American Society of Mechanical Engineers (ASME) will be applied as needed either to design a new facility or to determine what modifications need to be made to an existing one. This presentation will not cover any environmental permitting topics that might involve the EPA or any other environmental agencies. However, any changes to existing permits should be reviewed by an environmental consultant to determine if any changes to existing air and water permits are required if hydrogen is introduced to an existing facility.

The quantity and state of hydrogen that will be onsite is the first thing to consider. This will determine will affect the design of building utilities such as wall types, ventilation, sprinkler systems, electrical systems, etc. Separation distances and set-backs for both indoor and outdoor installations will also be determined by state and quantity. When putting together a facility layout, one needs to consider what rooms / areas of the facility will have hydrogen, the volume of hydrogen present, gaseous or liquid state and the pressure in storage, piping and use point.

Determining what other hazardous chemicals per the IBC/IFC will be in the area will be important establish separation distances. It will be necessary to know the hazard(s) associated with each chemical and how much will be present. These hazards are listed as flammables, pyrophorics, unstable reactives, cryogenics, oxidizers, corrosives, toxics/highly toxics, etc.

Adequate ventilation of an indoor facility containing hydrogen is critical to hydrogen safety and affects many aspects of the building design including when and how to sprinkle, electrical classification areas and even if a building is suitable to contain any hydrogen at all. Since hydrogen is lighter than air, it is important that exhaust fans and vents be located close to the ceiling to ensure that there is nowhere that hydrogen can pool to create an ignitable mixture. NFPA and the National Electrical Code (NEC) provide requirements on how ventilation systems for buildings containing flammable gases lighter than air should be designed.

Electrical classifications for both indoor and outdoor facilities are a factor to consider when hydrogen is involved. Since gaseous hydrogen has a very large flammability range, it can ignite quite easily in the presence of a spark. Therefore, NFPA has guidance on what electrical classifications are required for various applications of hydrogen. Electrical systems include but are not limited to building facilities such as lighting, power distribution panels and ventilations systems. They also include process equipment such as motors and instruments such as transmitters.

Proper pipe design is critical to a safe hydrogen system. Embrittlement and venting are the two most important issues that must be addressed in a hydrogen piping system design. ASME, NFPA and the CGA all offer guidance on safe pipe design of hydrogen distribution piping and for hydrogen venting systems. These guidelines include the design of a proper hydrogen vent stack. All relieving devices must be piped to a vent stack that is engineered to allow for a flare, if necessary. Appropriate material selection for hydrogen piping and pipe components depending on the process conditions, how to relieve pressure or shut down and bleed a hydrogen piping system safely.

Finally, some of the codes and standards place some emphasis on information, education and training of staff and employees. NFPA details some signage requirements whenever a flammable gas, particularly hydrogen is present. There is also an expectation that staff and employees at the facility receive a level of training in hydrogen safety that is adequate for them to perform their duties safely.

Each of the above topics will be expanded upon and covered in more detail during the presentation in a very practical way, discussing the applicable codes, standards and best practices and how to apply them in various scenarios. Such scenarios can include liquid and gas storage applications, the use hydrogen cylinders and some point-of-use applications.