DCS @ < 60 feet

[AzAtty]

DCS can manifest any time there is a significant change in ambient pressure. For example, DCS symptoms have occurred in flight crews whose airplanes have rapidly depressurized (for comparison, 18,000 ft = 1/2 ATM, a relative change equal to 30FSW to the surface), and astronauts breath pure oxygen prior to EVAs to offgass nitrogen (Shuttle pressure is 1 ATM, suit pressure is less). Although it may be STATISTICALLY RARE that DCS will manifest in dives less than 60 feet, it can certainly happen.

 

[Thalassamania]

DCS can manifest any time there is a significant change in ambient pressure. For example, DCS symptoms have occurred in flight crews whose airplanes have rapidly depressurized (for comparison, 18,000 ft = 1/2 ATM, a relative change equal to 30FSW to the surface), and astronauts breath pure oxygen prior to EVAs to offgass nitrogen (Shuttle pressure is 1 ATM, suit pressure is less). Although it may be STATISTICALLY RARE that DCS will manifest in dives less than 60 feet, it can certainly happen.

EVA Suit pressure is 0.3bar, the oxygen prebreathing is done to scrub nitrogen out and prevent bends when ambient is lowered by 70%. The reason for the low pressure is make the joints easier to design, build and use.

 

[paixx01]

what i want to ask is since i dive without a computer for over 100 dives and without a watch, generally the alum80 is going to run out of air before one deco's when one is above 60feet ?

 

[Thalassamania]

what i want to ask is since i dive without a computer for over 100 dives and without a watch, generally the alum80 is going to run out of air before one deco's when one is above 60feet ?

In the old days we'd do 60 for 60 as a no-D limit (they've cut back 5 to 10 minutes now). An experienced diver (with a SAC rate on the order of 0.4) can make it to 60 for 60 and still have 10% of the gas left in the tank.

 

[paixx01]

so a computer is advisable for any dive below say 40 feet?
i don't really wanna use one , er, buy one

 

[Prostar]

man im not even sure if i could dive in 4ft of water

I'm pretty good at it now. Now I want to get that coveted Deep End certification.

 

[Thalassamania]

so a computer is advisable for any dive below say 40 feet?
i don't really wanna use one , er, buy one

Or a watch and depth gauge.

 

[ae3753]

so a computer is advisable for any dive below say 40 feet?
i don't really wanna use one , er, buy one

No computer necessary, but I agree with Thalassamania and that you need at least a watch and depth gauge.

Obviously, if you do a second dive that day, you can obtain a deco obligation on the second 60' dive.

 

[Kray_Z]

No computer necessary, but I agree with Thalassamania and that you need at least a watch and depth gauge.

Obviously, if you do a second dive that day, you can obtain a deco obligation on the second 60' dive.

yeah just get a bottom timer.. does both :14:

 

[nolatom]

what i want to ask is since i dive without a computer for over 100 dives and without a watch, generally the alum80 is going to run out of air before one deco's when one is above 60feet ?

A watch would only cost you 30 bucks, and the tables are available on-line for nothing.

Why would you risk it without these?