1/3 Rule?

[oldschoolto]

Well, its a bit late to find out that you've got gas for 3 minutes for both of you after your buddy has ran out and youre 4 minutes from the surface?

Not really.... You now know that you will run out before surfacing, And can... A: try and slow breathing rate... B: have the better diver do a OOA free assent as you near 50-60 feet... WORK THE PROBLEM.... And also why I love hanging a deco bottle at 20' from the boat... You just got to make the bottle and then make up any deco time....

Jim...

 

[Tigerman]

Not really.... You now know that you will run out before surfacing, And can... A: try and slow breathing rate... B: have the better diver do a OOA free assent as you near 50-60 feet... WORK THE PROBLEM.... And also why I love hanging a deco bottle at 20' from the boat... You just got to make the bottle and then make up any deco time....

Jim...

Yeah, great plan - much better than actually planning your gas consumption and reserver beforehand so you dont get into the situation in the first place...

 

[scjoe]

If you are 4 minutes from the surface, hustle it up at 60 fpm now you are only 2 minutes from the surface.

 

[oldschoolto]

Yeah, great plan - much better than actually planning your gas consumption and reserver beforehand so you dont get into the situation in the first place...

My post was to the post saying it's not much help to know you are gonna run short on gas...

I didn't say that should be a "PLANNED" dive... I said that knowing you're short on gas lets you do more than have two divers sucking a tank dry and not knowing it.. Work the problem.... Work the problem.... Work the problem.... You need to be always open to new problems and ways to overcome them..

Jim....

 

[windapp]

When was the last time you sent out your SPG and mechanical depth gauges for calibration?

When was any shop?

I will put a buddy's rig on my tank, and cross check the reading against my own. Your SPG should be checked when your regulators are serviced. It's not calibration. It is a simple check.

 

[flots am]

That "rock bottom" has opened my eyes, and shockingly so! Clearly one very important factor was not taken into consideration in everything I was told. And that was, 2 of us might be breathing that air. An just how much air we will both be consuming for a safe ascent.

Your answers at the least might of saved a very dangerous situation for me or a buddy, and at worst (case) might of saved a life in the future.

Gas planning is important, but if you're following your Open Water training, the worst you'll have if you run out of air is embarrassment. As an Open Water Diver, you should never be anyplace (physical overhead or decompression obligation) where you and your buddy can't surface.

Running out of air is bad, and should be avoided, and knowing how to plan to not run out of air, and then execute that plan will make you a better and safer diver, but if running out of air is fatal or dangerous, you're not on a dive you're qualified for.

flots.

 

[buddhasummer]

Gas planning is important, but if you're following your Open Water training, the worst you'll have if you run out of air is embarrassment. As an Open Water Diver, you should never be anyplace (physical overhead or decompression obligation) where you and your buddy can't surface.

Running out of air is bad, and should be avoided, and knowing how to plan to not run out of air, and then execute that plan will make you a better and safer diver, but if running out of air is fatal or dangerous, you're not on a dive you're qualified for.

flots.

I like that and with your permission will use it.

 

[flots am]

> I like that and with your permission will use it.

Any time.

 

[buddhasummer]

> I like that and with your permission will use it.

Any time.

Cheers, appreciated.

 

[maniago]

I will put a buddy's rig on my tank, and cross check the reading against my own. Your SPG should be checked when your regulators are serviced. It's not calibration. It is a simple check.

You guys are forgetting that an SPG is a mechanical gauge, essentially based on a spring (ok Bernoulli tube, whatever). It has an accurate sweet spot, probably around 2200psi. The accuracy drops off as you get on either side of that, precipitously at the edges (maybe ~400 &~4000 psi). It will spec out perfect on the bench, and have the associated inaccuracies at the margins. Go to the mfgs website and look up the specs if you want them (we used to call this "good enough engineering"...)

If you want better across more of the range, then a transducer is the only accepted equipment (read: wireless), and even those are bell curved (albeit less so) but still matched to their pressure "ranges".