But you did violate the NDL according to the planner, 100' max depth with a run time of 80 minutes is way over the 20 minutes max allowed - correct?
The problem I was trying to point out is that tables (
All of those kinds of tables) do not address a minimum ascent rate--they assume you will ascend at
close to a given rate, but they don't talk about ascending
too slowly. At some point, you can ascend so slowly that you are in violation of the NDLs as would be determined by a computer. Obviously, the dive I described was more of a multi-level dive, but how do you differentiate between a multi-level dive and a lingering, slow ascent, and how do you differentiate between a multi-level dive and a deep stop?
What is the correct way of defining the "time" under any given depth in the PADI RDP - I was of the understanding it was total bottom time but I've also heard it said as total time under the water....???
As Tursiops said,
when using the tables, bottom time is the time from descent until you make your
direct ascent to the surface. So you could say that I had only 5 minutes of bottom time, or you could describe some pauses along the way as multi-level stops, meaning I it was quite some time before I finished my bottom time and began the true ascent. When using a computer, you normally count total run time for purposes of logging dives.
I get what you are saying about the no set too slow ascent rate but in that sense, defining time as the total time under water sort of covers that....
Total time under water really only works if you are using a computer, which recalculates your dive continually. As I hope I showed in the comments above, if you are using tables and doing the kind of slow, multi-level ascent I am describing, you really don't know what is going on. Bottom time ends with a DIRECT ascent to the surface. It can be slower than the ascent rate associated with the table, but if it is a lot slower, you are doing a multi-level dive, and the tables don't cover those. If you go slowly enough, at some point you will go into deco, but you won't know when that is.
I think you can see why I decided not to write my article on NDL ascent rates. After all my research, I have less to say that is helpful than I did before, when I thought I knew what I was talking about.