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April 2015 BSJ

Hydrogen and Fuel Cells: Focusing on Facility Safety Requirements continued Compliance with NFPA 70®, National Electrical Code® (NEC®)2, is required by IFC 2309.2.3, 5803.1.5, 5303.8 and 5503.6. The NEC® provides the fundamental requirements for equipment classification, and NFPA 2 provides specific details on the extent of classified areas. Purged enclosures can be used when classified equipment is unavailable or an alternative to such equipment is needed. Table 2 provides the extent of classified locations around common hydrogen equipment. THE CERTIFICATION CHALLENGE The use of listed or approved equipment is a fundamental requirement in the ICC codes, and its applicability to hydrogen and fuel cell equipment is no exception. For fueling facilities, the IFC requires that “hoses, hose connections, compressors, hydrogen generators, dispensers, detection systems and electrical equipment used for hydrogen shall be listed or approved for use with hydrogen. Hydrogen motor-fueling connections shall be listed and labeled or approved for use with hydrogen” (2309.2.2). Similar language appears in requirements for other hydrogen applications, sometimes more globally. For example, IFGC Section 704.1 states, “gaseous hydrogen systems, equipment and machinery shall be listed or approved.” The challenge with these requirements is that the listing process for rapidly changing products consistent with developing technologies tends to be cost-prohibitive for equipment providers (each revision to the equipment requires recertification). Couple that with low demand for early market applications, and the result is that few components and systems are currently listed. The scarcity of listed equipment places an extraordinary burden on code officials to ensure (approve) that products include the appropriate inherent or automatic safety measures. Adding to this problem is confusion about equipment labeling. For example, some enclosures for fuel cell or dispensing equipment are provided with a listing label. In most cases, the label is intended to apply only to the enclosure, not the equipment contained inside (Figure 1). Until more listed products are available, one option is for approving authorities to rely on third-party certification (or field certification) to validate equipment acceptability. An independent group, the Hydrogen Safety Panel, is drafting a certification guide to facilitate timely project permitting and approval by code officials. The guide will identify listing requirements in the IFC, IFGC and NFPA 2 for hydrogen equipment and suggest Table 2. Electrical Equipment Requirements for Bulk Systems Location Classification* Distance Area containing gaseous hydrogen storage, compression or ancillary equipment Class 1, Division 2 Up to 15 feet from storage/ equipment Area containing liquefied hydrogen storage Class 1, Division 2 Up to 25 feet from the storage equipment, excluding the piping system, downstream of the source valve Class 1, Division 1 Within 3 feet from points where connections are regularly made and disconnected Interior of dispensing equipment Class 1, Division 1** Up to the support mechanism (anchoring the dispenser) or connection to the ground level Exterior of outdoor dispensing equipment Class 1, Division 2 Up to 5 feet from dispenser Exterior of indoor dispensing equipment Class 1, Division 2 Up to 15 feet from the point of transfer from floor to ceiling Outdoor discharge from relief vents Class 1, Division 1 Up to 5 feet from the source Class 1, Division 2 5-15 feet from the source Discharge from relief vents within 15 degrees of the line of discharge Class 1, Division 1 Within 15 feet from source * All equipment shall be rated for Group B applications (NFPA 70-500.6). ** This requirement is expected to change to Class 1, Division 2, in the 2016 version of NFPA 2. Derived with permission from NFPA 70-2014®, National Electrical Code®, Copyright © 2013, National Fire Protection Association, Quincy, MA. APRIL 2015 | 47


April 2015 BSJ
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