Q: A local fire inspector approved our outdoor storage shed for full oxygen cylinders. Now a surveyor says it is not compliant because the shed is made of wood, and the accumulative total of oxygen stored exceeds 20,000 cubic feet and must meet NFPA 50 for bulk oxygen storage. Who is correct?
A: Sometimes it doesn’t matter who is correct, but more importantly what the standards and regulations require. First, I would disagree that oxygen stored in cylinders in quantities exceeding 20,000 cubic feet requires compliance with NFPA 50 Standard for Bulk Oxygen Systems at Consumer Sites. NFPA 50 is for a bulk oxygen system which is defined as an assembly of equipment, including cylinders, pressure regulators, safety devices, vaporizers, manifold, and interconnecting piping. It does not appear that you have that assembly; just the full cylinders of oxygen. However, oxygen stored inside the building in quantities exceeding 3,000 cubic feet must be stored in 1-hour fire rated enclosures that are constructed with non-combustible materials, according to NFPA 99 (1999 edition), section 4-18.104.22.168. But a storage shed outdoors that is at least 10 feet from the healthcare facility is not required to be fire-rated. Keep in mind that just because a local AHJ approved this arrangement, that does not mean it will be (or must be) acceptable to all AHJs. Each authority has the right to interpret the situation to his or her own understanding, and you need to comply with the most restrictive..