The Airgas facility in Flagstaff, 2004. Saw their servicing facility. One tank of LOX fed a manifold. On the manifold, takeoff fittings labeled "welding", "medical", and "aviator breathing" along with the appropriate warnings, hazmat labels, regulatory gobbledegook. One LOX tank, one manifold. I'll believe what the reference said. I'll also believe what I saw in practice by one of the biggest and most reputable companies in the business, a subsidiary of one of the largest companies in the business worldwide, to meet those standards. Of course, the world has changed a lot since 2004.