A question I have asked for years, starting back in the late 1980’s when I began wearing SCBAs. I have asked this question to dozens, maybe hundreds of people, way smarter than me, and everyone was stumped. So today I had a lengthy discussion on SCBAs and the question was asked of me again. So I decided to ask Gemini+ and Super Grok. I liked the Gemini+ answers better and have shared it below.
The standard pressure of 2216 psig (pounds per square inch gauge) for low-pressure SCBA cylinders is a peculiar number that often leaves safety professionals like yourself wondering why it wasn’t a round figure like 2000 or 2500 psi.
In short, 2216 psig is essentially the American “translation” of the European 150-bar standard, fine-tuned to hit the 45-cubic-foot air-volume target.
NOTE: I am either wearing an MSA or SCOTT SCBA, so that is why I chose to use an MSA bottle. An unpaid endorsement for both brands.