Yourself as well
However, having to read time after time of how Americans have shot British troops can get a bit old over here. You do know that America was responsible for 17% of its own troops' deaths, and around 10% of British deaths in the first Gulf war?
The above includes a daring raid by tankbusters on a convoy of a British convoy (though they were cleverly disguised by having flourescant panels to try and prevent the trigger happy American pilots from using them as target practice).
I suggest a read of
this article to see how much the Pentagon values the British troops helping out in the Middle East.
The Americans have changed little since they opened fire on my Grandad's ship on DDay+1. the American boat mistook a cable laying boat (with a huge drum of wire on the back to lay the telephone cable from Britain to France) with a Canadaian escort for a U-Boat.
There is an all too well documented history of American servicemen shooting first, and thinking second.
To add to Ski's point:
Oxygen toxicity while breathing 100% O2 at depth is going to occur in comparatively shallow water. From my quick calculations (based on the diving partial pressure learnings I have just started) you are going to be looking at 5 metres or so. The NOAA guideline is 45 minutes at 1.6 bar absolute of oxygen. In a 100% oxygen mix you would get 45 minutes of dive at around 6 metres. As a result 100% oxygen is rarely used on an open circuit, except for when aiding decompression from long, deep dives (usually with almost hypoxic mixes including large parts of helium).
The above will have some safety factor in it, but I doubt you can safely breach 10 minutes for any reasonable amount of time without risking oxygen toxicity.
