Actually Cajun, in that pic I'm wearing a Scott SKA-PAK which is an SABA with 100' of 1/4" air hose hooked up to a 12 bottle cascade system. We primarily supply SABAs since it's a hell of a lot faster to set up for long term jobs (3-4 hours under air) than to have to keep swaping out SCBA bottles. Not to mention trying to get in/out of a confined space, even with removing the SCBA, is a nightmare, let alone working/maneuvering.
Here's one of our 9,600lb 12 300ft^3 bottle trailers behind my SuperDuty. Holds 36 man-hours of air and we have a bulk trailer that holds 22 300ft^3 4500psi which can fill 4 of these trailers that weights 12,600lbs.