"Riding your Computer Up" vs. "Lite Deco"

[DevonDiver]

I don't think calling people names in discussions like this adds anything constructive to the conversation, and only calls the credibility of the name-caller into question. When it's done by a dive professional, it undermines their professionalism.

You may have some valid points, but the manner in which you're making them is, at best, counter-productive to the discussion ...

... Bob (Grateful Diver)

You are, of course, absolutely right.

I'll disengage for a while and leave the internet divers to astound themselves with their own brilliance and insight

 

[Scuba J7]

No, it would not.

So the amount of nitrogen in your body has nothing to do with DCS risk?

 

[redacted]

So the amount of nitrogen in your body has nothing to do with DCS risk?

That is not what you asked.

But while we are on that line of thought, we know that drinking too much water can kill you. So, is drinking 2 glasses of water more risky than drinking one glass?

At 40 ft, is PG F at a greater risk for DCS than PG E? How about at 130 ft? (On USN tables)

Until you start to play around at th edge of the limits, DCS risks are negligible for most divers.

 

[Scuba J7]

That is not what you asked.

But while we are on that line of thought, we know that drinking too much water can kill you. So, is drinking 2 glasses of water more risky than drinking one glass?

At 40 ft, is PG F at a greater risk for DCS than PG E? How about at 130 ft? (On USN tables)

Until you start to play around at th edge of the limits, DCS risks are negligible for most divers.

We are talking about limits, specifically NDL
Yes more nitrogen in your body = higher risk of DCS even if it's negligible it is still more.

Water will not kill you, an inbalance in electrolytes will. Certain types of water will cause this e.g. Distilled

 

[stuartv]

If an instructor cant explain why one computer is in deco and one isn't on the same dive, well they shouldn't be instructors. This thread has just turned into people that like to argue.

So if dsat is considered safe and everything else is more conservative (recreationally) then what the hell is the problem? You're not going to force one deco algorithm on every manufacturer and training agency, so what's your solution?

The point is about what people are to do after they have graduated from OW and are diving on their own. Nothing to do with having an instructor handy to ask "why do these two computers show different numbers?"

I don't have a problem. What problem do you think we're trying to solve, that you are asking me for a solution for?

I definitely don't see any reason to make manufacturers all adopt the same algorithm. I was simply refuting the notion that was posted that NDL is a very definitive line, dictated by the [decompression] model. It's not.

 

[Bob DBF]

It used to be the case that computers were conservative and tables less so.

As for "computers were conservative", the first ones ran the Navy tables for multilevel dives. The Navy tables were not calculated for doing multilevel diving.

Unless you are doing a square profile at the table depth, the tables make the dive more conservative. Dive at 51' calculate at 60', follow the shore up from 60' to 15' the time at depth ends at 15' when you make your direct ascent to the surface. This assumes that the diver uses the tables properly.

NDL is a sharp black line in a big gray area, and it behooves a diver to have a good enough understanding of decompression theory to decide where they want to be in that continuum, or pick a dive computer at random.


Bob

 

[Scuba J7]

The point is about what people are to do after they have graduated from OW and are diving on their own. Nothing to do with having an instructor handy to ask "why do these two computers show different numbers?"

I don't have a problem. What problem do you think we're trying to solve, that you are asking me for a solution for?

I definitely don't see any reason to make manufacturers all adopt the same algorithm. I was simply refuting the notion that was posted that NDL is a very definitive line, dictated by the [decompression] model. It's not.

The tables I use have a defined NDL, pretty sure the whole point of tables is to set parameters.

 

[stuartv]

The tables I use have a defined NDL, pretty sure the whole point of tables is to set parameters.

Right. And a different set of tables based on the same model might have different NDLs. Thus, as I've said several times now, the model does not dictate a very definitive line. Each specific implementation, whether it's implemented in the form of tables or implemented in computer firmware, with all its parameters set, including ones set by the user, are the only thing that can give you a clear, definitive line.

 

[stuartv]

You can use PADI tables. I might use NOAA tables. Someone else might use SDI tables. They might all be based on a neo-Haldanian model. Yet they still have different numbers. The model does not dictate a clear, definitive line.

 

[Scuba J7]

You can use PADI tables. I might use NOAA tables. Someone else might use SDI tables. They might all be based on a neo-Haldanian model. Yet they still have different numbers. The model does not dictate a clear, definitive line.

Each table has a clearly defined line that I see. I wouldn't expect them to be the same because they all use a different algorithm, even if just slight.

Most cars engines are based on an Otto cycle, yet they don't all put out the same hp per litre.