Open Your Mouth, And You're Dead

[infinite monkey]

No way. You have two things against you there: nitrogen narcosis and compression. Oh, and breathing.

You can't just shoot to the top. They didn't say anything about decompression. If you're not using equipment you can't stop at the intervals needed so you don't, like, die.

I call poppycock.

http://en.wikipedia.org/wiki/Deep_diving

Amongst technical divers, there are certain elite divers who participate in ultra-deep diving on SCUBA (using closed circuit rebreathers and heliox) below 660 feet (200 m). Ultra-deep diving requires extraordinarily high levels of training, experience, fitness and surface support. Only eight (or possibly nine) persons are known to have ever dived below a depth of 800 feet (240 m) on self contained breathing apparatus recreationally.[8][9][nb 6][10] That is fewer than the number of people who have walked on the surface of the moon. The Holy Grail of deep SCUBA diving was the 1,000 ft (300 m) mark, first achieved by John Bennett in 2001, and has only been achieved five times since. Dives of this nature have been impossible to verify - proof being as tangible as faith more often than not. Since the recent introduction of depth gauges capable of reading to 330m it is unlikely that such records will be attempted in the future.

In 2003 Mark Ellyatt claimed dives to depths of 260m and 313m.

Dealing with depth
Technical divers preparing for a mixed-gas decompression dive in Bohol, Philippines. Note the backplate and wing setup with sidemounted stage tanks containing EAN50 (left side) and pure oxygen (right side).Divers carry larger volumes of breathing gas to compensate for the increased gas consumption and decompression stops.
Rebreathers manage gas much more efficiently than open circuit scuba, but are inherently more complex than open circuit scuba.
Use of helium-based breathing gases such as trimix reduces nitrogen narcosis and stays below the limits of oxygen toxicity.
A diving shot, a decompression trapeze or a decompression buoy can help divers return to their surface safety cover at the end of a dive.

Deep Diving Depth[nb 1] Comments
40 feet/12 metres Recreational diving limit for divers aged under 12 years old and beginner divers.
60 feet/18 metres Recreational diving limit for divers with Open Water certification but without greater training and experience.
100 feet/30 metres Recommended recreational diving limit for divers.[1] Average depth at which nitrogen narcosis symptoms begin to appear in adults.
130 feet/40 metres Absolute recreational diving limit for divers specified by Recreational Scuba Training Council (RSTC)
Maximum depth reachable by a French level 2 diver accompanied by an instructor (level 4 diver), breathing air.

180 feet/55 metres Technical diving limit for "extended range" dives breathing air to a maximum ppO2 of 1.4 ATA.
200 feet/60 metres Maximum depth reachable by a French level 3 diver accompanied by another level 3 diver, breathing air.
218 feet/65 metres Depth at which compressed air results in an unacceptable risk of oxygen toxicity.
330 feet/100 metres Technical diving training limit for divers breathing trimix. Recommended technical diving limit.
509 feet/155 metres Record depth for scuba dive on compressed air.
660 feet/200 metres Absolute limit for surface light penetration sufficient for plant growth, though minimal visibility possible farther down1,083 feet/330 metres World record for deepest dive on SCUBA
2,000 feet/610 metres Navy diver in Atmospheric Diving System (ADS) suit