Isn't Nitrox, trimix and diving below 130ft really commercial diving without the $$$$

[elijahb]

Originally Posted by in_cavediver

I think there is a slight disconnect here. First, in general terms, N2 loading in tissues behaves like the gas laws describe. I am sure there are a few subtle biochemical changes associated with exertion that modify the uptake rates but that isn't the real reason why exertion is bad for DCS.

Exertion as per DCS risk is better explained in the bubble models. IE, for a given N2 loading, what is the size and numbers or bubbles produced. Exertion lead to more micro bubble nuclei and hence, the potential for more bubbles, even if the N2 loading is within tolerance for a tissue model.

Either way, exertion at depth is bad for LOTS of reasons.

What about saturation diving?

[in_cavediver]

Originally Posted by elijahb

What about saturation diving?

The interesting thing about saturation diving is the compression periods and decompression periods. The question arises on the life span of the micro nuclei for bubble formation. Does exertion followed by 10 hours of rest at depth behave differently that exertion followed by immediate ascent? I don't know the answer but I am quite sure the saturation protocols account for this. The time frames we are talking about are quite long, days and weeks sometimes.

Simply put, the tables used bring divers who work at depth up safely and as quickly as is safe. They don't really care if exertion is problem as they have to do exertion at depth and then safely get decompressed.

Perhaps a commercial diver can chime in here with more information?

[Penguino]

I think nitrox should be removed from the original list, at least at recreational levels. Yes it is more planning, but it is easily avoided. I don't think they would let rec divers use it if it wasn't safe

[Black-Gorrilla]

im glad i found this thread (by mistake might i add) i like the discussion thats going on.

[ChrisA]

Originally Posted by WaScubaDude

.... "Tech" divers are some of the very best divers no doubt but also the ones making calculations about what could have been done, when the truth is; diving is dangerous and "tech" diving is very dangerous....

Dangerous, yes but if you look at who accidents happen to the group most at risk are what we might call relativly inexperianced vacation divers. These are people doing dives that should be easy. They are typically in warm clear water and superviser by a DM. But their problem and root cause of the accidents are that they don't dive enough to keep their skill current. Typically they do something stupid like rushto the surface because their mask flooded or panic when he BC leaks and they are sinking even with a full tank of air.

We see the same thing with travel. Some people think airplanes are unsafe but if you look at the numbers, driving to work is far less safe. When I look at the numbers Dan publishes I see most deaths are really medical problems that just happened to occure while diving. If you ignore these non-accidenets thenext larest group is the one I pointed out above. After that it is all over the map with not trend unless you group everyone who dove a dive outside of their training