as a former guard of 10 years, i can honestly say that while you have a legal "out" in such circumstances, you still have a moral or ethical obligation. personally, i don't think i'd be able to live w/ myself if i didn't go b/c sharks or whatever...the very nature of the job entails putting your life at risk for another. the captain of the first patrol i worked for put it best: you have to go, you just don't have to come back.
i applaud the guy for what he did; screw the rules, screw the bs, save the life & deal w/ the fallout later.
Hey man, why did you cut my quote in a fraction? If you are going to quote me, at least quote my whole write-up, including: "At the same time, he made his mind and acted in the best interest of saving another's life. I think that this lifeguard will be back on the stand next week."