Ascent Rate - Deep Dives

[Diver0001]

Why the switch from horizontal to vertical??

Partly a visual image to get the idea across and partly because what I see around me is that if you don't actually stop and start going straight up that a lot of people tend to keep swimming across the bottom. If you feel the need to do it horizontally then feel free but that's a lower priority than an effective ascent.

R..

 

[jonnythan]

There are lots of people who ascend horizontally, myself included. Specifying that it's not an ascent unless you're vertical is kind of silly.

The ascent starts when you start moving upwards at ~ 30 fpm. Anything before that (whether you're horizontal, vertical, or standing on your head ) is the dive.

 

[Diver0001]

There are lots of people who ascend horizontally, myself included. Specifying that it's not an ascent unless you're vertical is kind of silly.

The ascent starts when you start moving upwards at ~ 30 fpm. Anything before that (whether you're horizontal, vertical, or standing on your head ) is the dive.

I figured you'd say that. Yes an ascent is an ascent, even fins first, I don't care.

What I'm trying to get across is (and if you look around you when you're diving in groups of divers who have not yet drunk the kool-aid you'll see this very clearly) that often times (not always but often) if you don't stop them from swimming forward before the ascent and then go straight up that they'll give you the thumbs up and keep swimming over the bottom. They *think* they've started to ascend, but they haven't. This is a skills issue common to many divers (even some experienced ones).

I'm glad you don't have that problem but keep in mind that a lot of people do and they'll be reading this thread. They don't care how you do it, they don't care how I do it and with any luck these posts will get them thinking about how they ascend instead of wondering (with all due respect to Jim, who has started thinking about it) how they keep "running out of NDL".

R..

 

[jonnythan]

We are in aggressive agreement

 

[Diver0001]

We are in aggressive agreement

LOL

I'm glad because I was just about in the mood to shake that DIR poster boy smile right off your face...

R..

 

[rockjock3]

What I'm trying to figure is this: is there a goal, an ideal ascent rate? Of course, too fast (over 30ft/min) is bad, and my computer will throw in a mandatory stop if I exceed 33 fpm continuously or 39 fpm momentarily. But too slow is also bad, cause you may suddenly run out of NDL time.

So if you are deep, and need to start offgassing, is the goal to ascend at around 30fpm, or is slower really better?

This is a related question in a way. I am new to diving but everything that I have read and been taught says that a proper ascent rate is 60fpm or slower. Yet I see people all over the boards spitting out the proper ascent rate as 30fpm or slower. I know slower is better but what is the truth in this? My dive computer book, the OW dive book, the PADI dive tables and the PADI OW dive video all state the 60fpm rule and nowhere mention the 30fpm rule.

I am not calling out anybody on this I just want to know where the numbers come from and which are correct. Thanks.

Jay

 

[jonnythan]

My books and tables say 30 fpm..

 

[rockjock3]

My books and tables say 30 fpm..

I see people that say the 60fpm is 20 years ago. My table is the PADI dive table updated 2003 and my dive book is the 2004 revision and there is no mention of 30fpm. Is the 30fpm maybe from another of the dive organizations? What is the date on your tables and books? My dive computer is also a Uwatec Pro and is a newer model and states the 60fpm in the instruction manual as where the computer will warn you if you exceed it.

Again I am new to diving and not trying to tell anybody they're wrong. I also know that slower IS better, to a point. I just want to know which numbers to follow. Thanks.

Jay

 

[jonnythan]

Weird. I'm not PADI, so I can't speak for their materials.

AFAIK the current standard is 30 fpm.....

 

[Diver0001]

I just want to know which numbers to follow. Thanks.

Jay

The number to follow is 30fpm. Eventually the PADI materials will be updated to address this but I suspect that the enormous costs of having the RDP retested using slower ascent rates is holding them back.

R..