Safely Using Hydrogen In Laboratories

American Welding & Gas, Inc. offers a large selection of hydrogen to Indianapolis, along with various other specialty gases. American Welding & Gas, Inc. often supplies hydrogen and other specialty gases to research laboratories and many other industries, so we felt it would be beneficial for our Indianapolis customers to be updated on the safe use of hydrogen in laboratories.

With rising costs associated with the limited volume of available helium, those tasked with operating and designing laboratory equipment are increasingly turning to their gas suppliers for hydrogen.  Hydrogen is used in a wide array of facilities from analytical laboratories to universities, medical research facilities, and chemical process buildlings.  Nonetheless, it is vital to understand the risks that are posed through the use, distribution, and storage of hydrogen along with the fire and safety code rules created 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) expressly created for hydrogen. These MAQ’s are discerned for each storage area, decided by storage in either an unsprinklered or completely sprinklered building and restricted further based on whether or not the hydrogen cylinders are being contained in gas cabinets. The corresponding volumes are expressed as standard cubic feet (cuft) of hydrogen at 1 atmosphere of pressure. In an unsprinklered building where not all cylinders are stored in gas cabinets, the MAQ is bounded to 1,000 cuft, whereas that number is doubled 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 defined by hydrogen use in control areas or utilizing outside storage, part II of this series will detail the infrastructure requirements for compliance.

We will further our discussion by selectively describing some of the main areas and needs for hydrogen installation in regards to fire-resistance rating and ventilation.Section 6.3.1.3.1 of NFPA details that for flammable gases saved or used in quantities larger than 250 cubic feet, a 1-hour fire resistance rated constrction should be employed for separation in the area. The compressed gas cylinders should be separated by 10’ or a nonflammable wall; but, they require separation by 20’ or a nonflammable wall having a minimum fire resistance rating of .5 hours from incompatible materials like oxygen. For places with hydrogen systems, necessary safety signs must also be permanently affixed.

Additionally, Section 6.16 describes that storage and use areas that are inside must be provided with ventilation, either mechanical or natural, so long as the natural ventilation is proven to be acceptable for the gas used. If using mechanical ventilation, 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 armed with an emergency power system for alarms, vents, and gas detection. The system must also keep track of gas density to ensure correct exhaust ventilation. Part III of this series will expand on the remaining NFPA 55 requirements for separation and controls.

To further explain the series discussing updates to NFPA 55 regulating the proper utilization of hydrogen in laboratories, we will continue our discussion selectively addressing some of the main areas and requirements for hydrogen installation in terms of separation and controls.Section 7.1.6.2 of NFPA 55 explains that any flammable or oxidizing gases need to be separated by 20’ from each other, while section 7.1.6.2.1 declares that this space can be limitlessly reduced 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 neccessity for compliance. Section 414.4 of the IBC demands that controls must be sufficient for the intended application, with automatic controls being required to function without fail. Section 2703.2.2.1 of the IFC calls for suitable materials for hazardous media, the main consequence 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 above 10,000°F.Aside from piping requirements, these codes also call for 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 final installment in the NFPA 55 series that details the the proper use of hydrogen in labs, we will finish our analysis by explaining uses where the need for hydrogen gas cylinders is higher than the Maximum Allowable Quantities (MAQ’s).

It is not unusual to encounter installations where the requirement for hydrogen is bigger than the MAQ’s, frequently in instrumentation uses 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 not achievable . The NFPA 55 code along with the IBC and IFC requirements make it possible for these volumes be in a building; however, certain building improvements are required, effectively demanding that the facility build a hydrogen shelter. These upgrades are comprised of enhancements to the structure fire rating, transportation, fire detection, a restraint on the amount of occupants, and a building story limit. These installations also have strict distancing requirements and floor and wall ratings as well. 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 several, smaller systems where the compressed gas cylinders may be set up completely in gas cabinets.

American Welding & Gas, Inc. is a dependable132] provider of hydrogen, along with many other specialty gases and specialty gas equipment to the Indianapolis area. Whether you are looking for specialty gases for use in your laboratory research, or any other industry in Indianapolis, American Welding & Gas, Inc. will have the products you need to complete your tasks. To find out more about American Welding & Gas, Inc. and our specialty gas products in Indianapolis, browse our website and catalog. We can be reached at or via email at peter.vanslyke@amwelding.com
 
 
 
Larry Gallagher
CONCOA 
2/10/2016