Safely Using Hydrogen In Laboratories

Arc3 Gases offers a large selection of hydrogen to Richmond, Virginia, along with many other specialty gases. Arc3 Gases often supplies hydrogen and other specialty gases to research laboratories and various other industries, so we felt it would be beneficial for our Richmond, Virginia customers to be knowledgable on the safe use of hydrogen in laboratories.

With rising costs correlated with the limited volume of available helium, those tasked with operating and designing laboratory equipment are beginning to turn more frequently to their gas suppliers for hydrogen.  From universities, to medical research facilities, analytical laboratories, and chemical process buildings, hydrogen is used at nearly all facilities.  Still, it is crucial to comprehend the risks that conincide with the storage, distribution, and use of hydrogen along with the fire and safety code rules controlled 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 altered the Maximum Allowable Quantities (MAQ) spelled out specifically for hydrogen. These MAQ’s are identified for each storage area, affected by storage in either an unsprinklered or entirely sprinklered building and further limited based on the hydrogen cylinders being contained in gas cabinets or not. The corresponding volumes are expressed as standard cubic feet (cuft) of hydrogen at 1 atmosphere of pressure. In an unsprinklered building in cylinders are stored in additional areas rather than simply gas cabinets, the MAQ is bounded to 1,000 cuft, whereas that amount is increased to 2,000 cuft if all cylinders are stored in gas cabinets. Likewise, for sprinklered buildings where not all cylinders are stored in gas cabinets, the MAQ is also 2,000 cuft. That volume is doubled to 4,000 cuft if all cylinders are stored in gas cabinets. NFPA further has limitations defined by hydrogen use in control areas or employing outside storage, part II of this series will explain the infrastructure needs for compliance.

We will extend our discussion by selectively describing some of the primary areas and necessities for hydrogen installation when referring to fire-resistance rating and ventilation.Section 6.3.1.3.1 of NFPA explains that for flammable gases stored or utilized in amounts greater than 250 cubic feet, a 1-hour fire resistance rated constrction will be utilized to separate the area. The compressed gas cylinders must be separated by 10’ or a fire-resistant wall; however, they require separation by 20’ or a noncombustible wall having a minimum fire resistance rating of .5 hours from incompatible materials like oxygen. For places that contain hydrogen systems, necessary safety signs must likewise be permanently set up.

Likewise, Section 6.16 details that indoor storage and use areas must be provided with ventilation, either mechanical or natural, so long as the natural ventilation has proved to be sufficient for the gas utilized. If being ventilated mechanically, the system must be operational while the building is occupied, with the rate of ventilation not reaching lower than 1 ft3/min per square foot of floor area of storage/use and being equipped with an emergency power system for alarms, vents, and gas detection. The system must also account for gas density to assure adequate exhaust ventilation. Part III of this series will detail the other NFPA 55 requirements for separation and controls.

To continue the series that explains updates to NFPA 55 governing the safe use of hydrogen in laboratories, we will continue our discussion selectively explaining some of the main areas and requirements for hydrogen installation in regard to separation and controls.Section 7.1.6.2 of NFPA 55 explains that any flammable or oxidizing gases must be separated by 20’ from each other, while section 7.1.6.2.1 dictates that this distance can be limitlessly decreased when separated by a barrier constructed 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 stated by NFPA 55, IFC, & IBC, creating a slightly more nuanced requirement 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 function without fail. 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 utilized 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 dictates that these brazing materials should have a melting point higher than 10,000°F.Aside from piping requirements, these codes also demand the use 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 last section in the NFPA 55 series about the hydrogen’s correct use within laboratories, we will conclude our discussion by describing applications where there is a greater demand for hydrogen gas cylinders than the Maximum Allowable Quantities (MAQ’s).

It is quite typical to find installations where the requirement for hydrogen is larger than the MAQ’s, most often in instrumentation applications and/or chemical reactions like hydrogenation. These are commonly found in installations using hydrogen where there is no outside storage and control to line pressures lower 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, significant upgrades to the building are needed, effectively demanding that the facility build a hydrogen shelter. The upgrades include advancements to the structure fire rating, transportation, fire detection, a restraint on the amount of occupants, and a building story limit. Not only this, but these installations likewise have strict requirements in regards to distancing along with floor and wall ratings. Although feasible, this scenario is not ideal and should be avoided if possible. A more efficient resolution would be to parcel the facility’s requirements into numerous, smaller systems where the compressed gas cylinders can be installed completely in gas cabinets.

Arc3 Gases is a dependable132] supplier of hydrogen, along with several other specialty gases and specialty gas equipment to the Richmond, Virginia area. Whether you need specialty gases for use in your laboratory research, or any other industry in Richmond, Virginia, Arc3 Gases will have the products you need to carry our your operations. To find out more about Arc3 Gases and our specialty gas products in Richmond, Virginia, browse our website and catalog. We can be reached at (804) 644-4521 or via email at nickk@arc3gases.com
 
 
 
Larry Gallagher
CONCOA 
2/10/2016