SAC Rate

[Soggy]

While every dive is a decompression dive, "NDL" dives have the decompression factored into the 30ft/min ascent rate with a optional safety stops. When you said you were making "decompression stops", I (rightfully) assumed you meant a mandatory/required stop, which is a dangerous thing to do when only carrying a single tank of non-redundant gas.

It sounds like what you actually did were safety stops, which are not mandatory stops and are perfectly acceptable when doing dives within the NDLs. There was semantic confusion.

Are you saying that you've never learned how to make a safety stop? Are you saying that you never use dive tables? Are you saying that in your OW/AOW classes, you weren't taught how to do safety stops or proper deco-stops? I'm really just about done with discussing this. Apparently, you're trying to make some point at my expense, while not just coming right out and stating things plainly. I'm not going to play verbal hide-&-seek with you. Communicate clearly so that we can have a discussion, or else forget it.

 

[Fish_Whisperer]

While every dive is a decompression dive, "NDL" dives have the decompression factored into the 30ft/min ascent rate with a optional safety stops. When you said you were making "decompression stops", I (rightfully) assumed you meant a mandatory/required stop, which is a dangerous thing to do when only carrying a single tank of non-redundant gas.

It sounds like what you actually did were safety stops, which are not mandatory stops and are perfectly acceptable when doing dives within the NDLs. There was semantic confusion.

Okay. My mistake was in calling them "deco-stops." My apologies.

 

[Soggy]

My apologies as well...still friends?

 

[Fish_Whisperer]

My apologies as well...still friends?

You betcha'!

See ya' below...

 

[Humu-out-of-Water]

My apologies as well...still friends?

You betcha'!

See ya' below...

Awwwww soooo sweet. :icescream

 

[dbg40]

Usually between .4 and .5 I can go a bit higher if I have to work, and a bit lower if im just fooling around.

 

[nyprrthd]

Cool, so now I can call it 'skills practice' instead of just being lazy

My thoughts, exactly!

 

[Nomad]

I should add, if I get my sac rate close to .4 on occasion I get a headache during the dive from what i presume is a CO2 buildup. It doesn't feel like I am retaining too much CO2 but the headache is the feeling I get when I breathe very slloooowwwwyyyy.

Justin... If I can offer some basic advice...

The CO2 retention that you mentioned can probably be controlled by making sure that you are exhaling the bottom half of your lungs.

When you are finished exhaling, use your diaphragm to extend the duration of your exhalation for another couple of seconds. (Out with the bad air, in with the good...)

I am betting that you will find that the headaches don't happen.

 

[Fish_Whisperer]

Usually between .4 and .5 I can go a bit higher if I have to work, and a bit lower if im just fooling around.

At that rate, at a depth of say, 40-60', how much bottom time do you get out of an AL80?

 

[Soggy]

At that rate, at a depth of say, 40-60', how much bottom time do you get out of an AL80?

Assuming .4:

60 ft = ~3 ATA

.4 cft/min * 3 ATA = 1.2 cft/min at depth
77.4 cft / 1.2 cft/min = 64.5 mins

That's if you breath it from 3000psi to 0 (not recommended!).