Safely Using Hydrogen In Laboratories

SYOXSA, Inc. offers a large selection of hydrogen to El Paso, along with many other specialty gases. SYOXSA, Inc. quite often supplies hydrogen and other specialty gases to research laboratories and many other industries, so we felt it would be useful for our El Paso customers to be updated on the safe use of hydrogen in laboratories.

With rising costs related to the limited volume of available helium, those who operate and design laboratory equipment are beginning to turn more frequently to their gas suppliers for hydrogen.  The use of hydrogen is found in several facilities, from medical research facilities to universities, analytical laboratories, and chemical process buildings.  Nonetheless, it is vital to be aware of the risks that are posed through the use, distribution, and storage of hydrogen along with the fire and safety code rules directed by the National Fire Protection Association’s Compressed Gases and Cryogenic Fluids Code (NFPA 55) and the International Fire Code (IFC) and International Building Code (IBC).

Recent updates to NFPA 55 have changed the Maximum Allowable Quantities (MAQ) specifically established for hydrogen. These MAQ’s are discerned for each storage area, affected by storage in either an unsprinklered or entirely sprinklered building and further limited based on whether the hydrogen cylinders are contained in gas cabinets or other locations. The corresponding volumes are expressed as standard cubic feet (cuft) of hydrogen at 1 atmosphere of pressure. In an unsprinklered building in which some cylinders are not stored in gas cabinets, the MAQ is bounded to 1,000 cuft, whereas that quantity is increased to 2,000 cuft if all cylinders are stored in gas cabinets. Likewise, for sprinklered buildings that do not have all cylinders stored in gas cabinets, the MAQ is also 2,000 cuft. That amount is multiplied to 4,000 cuft if all cylinders are stored in gas cabinets. NFPA further has limitations determined by hydrogen use in control areas or using outside storage, part II of this series will discuss the infrastructure needs for compliance.

We will continue our discussion by selectively describing some of the primary areas and needs for hydrogen installation in regards to fire-resistance rating and ventilation.Section 6.3.1.3.1 of NFPA explains that for flammable gases stored or employed in greater quanities than 250 cubic feet, a 1-hour fire resistance rated constrction shall be used to separate the area. The compressed gas cylinders should be separated by 10’ or a nonflammable wall; however, they must be separated by 20’ or a noncombustible wall that contains a minimum fire resistance rating of .5 hours from incompatible matters like oxygen. For locations with hydrogen systems, proper safety notices must likewise be permanently set up.

Likewise, Section 6.16 declares that storage and use areas that are inside must be ventilated either mechanically or naturally, so long as the natural ventilation is proven to be acceptable for the gas used. If using mechanical ventilation, the system must operate while the building is occupied, with the rate of ventilation being no less than 1 ft3/min per square foot of floor area of storage/use and having an emergency power system for alarms, vents, and gas detection. The system must also keep track of gas density to assure proper exhaust ventilation. Part III of this series will discuss the remaining NFPA 55 requirements for separation and controls.

In continuing the series detailing updates to NFPA 55 regulating the proper utilization of hydrogen in laboratories, we will further our discussion selectively describing some of the important areas and requirements for hydrogen installation in terms of separation and controls.Section 7.1.6.2 of NFPA 55 states that any flammable or oxidizing gases are required to be separated by 20’ from each other, while section 7.1.6.2.1 dictates that this length can be limitlessly decreased when separated by a barrier comprised of noncombustible material a minimum of 5’ tall that provides a fire resistance rating of at least .5 hours.

The safe use of controls in hydrogen systems are declared by NFPA 55, IFC, & IBC, creating a slightly more nuanced need for compliance. Section 414.4 of the IBC demands that controls must be good enough for the intended application, with automatic controls being required to operate fail-safe. Section 2703.2.2.1 of the IFC requires suitable materials for hazardous media, the main negative result being that 316L SS or copper piping shall be employed and identified in accordance with ASME A13.1 with directional arrows every 20’. The system should also contain no concealed valves or breakable connections, using welded or copper brazed joints where the piping is concealed. NFPA 55 requires that these brazing materials should have a melting point greater than 10,000°F.Aside from piping requirements, these codes also require the employment of emergency shutoff valves on supply piping at the point of use and source of compressed gas, along with backflow prevention and flashback arrestors at the point of use.

As the concluding part in the NFPA 55 series governing the safe use of hydrogen in laboratories, we will conclude our discussion by detailing employments where the need for hydrogen gas cylinders is higher than the Maximum Allowable Quantities (MAQ’s).

It is not unusual to come across installations where the requirement for hydrogen is bigger than the MAQ’s, frequently in instrumentation employements and/or chemical reactions like hydrogenation. These are often encountered in installations using hydrogen where there is no outside storage and control to line pressures smaller than 150 PSIG is unobtainable . The NFPA 55 code combined with the IBC and IFC requirements make it possible for these volumes exist within a building; however, important enhancements to the building are necessary, effectively requiring that the facility constructs a hydrogen shelter. These upgrades are comprised of improvements to the structure fire rating, transportation, fire detection, a limitation on the number of occupants, and a building story limit. Additionally, these instillations have stringent distancing regulations as well as floor and wall ratings. Although doable, it is best to avoid this scenario seeing as it is not optimal. A better answer would be to combine the facility’s requirements into numerous, smaller systems within which the compressed gas cylinders can be installed exclusively in gas cabinets.

SYOXSA, Inc. is a dependable132] provider of hydrogen, along with various other specialty gases and specialty gas equipment to the El Paso area. Whether you are looking for specialty gases for use in your laboratory research, or any other industry in El Paso, SYOXSA, Inc. will have the products you need to get the job done. To find out more about SYOXSA, Inc. and our specialty gas products in El Paso, browse our website and catalog. We can be reached at 915-771-7674 or via email at Esteban.Trejo@syoxsa.com
 
 
 
Larry Gallagher
CONCOA 
2/10/2016