Right. The O2 is used in first care for scuba injuries. At Channel Islands every boat has at least two cylinders of O2, and each island also had a stash of at least two cylinders. The commercial dive boats using the island also carry O2 routinely. I can recall at least a couple of occasions, converging on an accident scene and computing the amount of O2 remaining with the victim, who would arrive with O2 next, etc.<br><br>I would be very surprised if Isle Royale did not have medical O2 easily at hand. The diving there is often much colder and occasionally quite a bit deeper than most common scuba destinations.