combined air/eanx dive tables

A calculator for the group and the no-decompression limit of a dive.

Enter the dive depth and how long you stay on the bottom. Then see how many minutes you still have for the next dive without decompression.

RG · RT · BT · TT

1 This dive

RG—in

RGGout

SI60 min

RGFfor the next dive

D30 mSafety stop 3–5 min · 5 m

RT: 0 min
BT: 25 min
TT: 25 min

2 Next dive

RGFin

RG—out

SI—

RG—for the next dive

D18 mSafety stop 3–5 min · 5 m

RT: 36 min
BT: —
TT: —

RG memakai baris 30.5 m. RT berikutnya memakai baris 18.2 m.

RG is the group letter. RT is residual nitrogen. BT is bottom time. TT is RT plus BT. On the next dive, BT is the minutes you still have, and TT is RT plus BT. SI is the surface interval. D is depth. A safety stop of 3–5 minutes at 5 m is recommended deeper than 9 m.

Setelah kamu menyelam di kedalaman 30 m selama 25 menit dengan udara dan istirahat 60 menit, huruf grupmu turun dari G menjadi F. Nitrogen dari selam tadi masih ada di tubuhmu. Di kedalaman 18 m, sisa itu dihitung seperti 36 menit yang sudah kamu habiskan. Karena itu kamu masih boleh 24 menit di dasar tanpa dekompresi.

What the words mean

Air: The usual mix. It is 21% oxygen, and almost all the rest is nitrogen.
EAN32: Nitrox with 32% oxygen. EAN36 means 36% oxygen. More oxygen than air, and less nitrogen.
Oxygen: The percent of oxygen in the cylinder. Air is entered as 21. EAN32 is entered as 32.
PPO2: PPO2 stands for partial pressure of oxygen. It is how hard the oxygen presses on you at that depth. The number rises as you go deeper.
Max PPO2: The oxygen limit you allow. Many recreational divers use 1.40.
Bottom time: How long you stay at the dive depth, in minutes.
Surface interval: How long you stay on the surface between two dives. Nitrogen leaves during this rest.
Next depth: The depth you plan for the dive after the rest.
Group: A letter for the nitrogen you still carry. A is the least. Later letters mean more nitrogen.
New letter: The group letter after the surface rest. It is usually lower than the letter you surfaced with.
RG: The nitrogen group letter on the table. In is the letter before the dive. Out is the letter when you surface. Next is the letter after the rest, and that letter starts the following dive. The first dive has no letter yet.
D: The dive depth, in metres.
RT: RT is residual nitrogen time. It is nitrogen left from the earlier dive, written as minutes. The first dive is usually 0.
BT: BT is bottom time, the actual time on the bottom, in minutes.
TT: TT is total time, RT plus BT.
SI: SI is the surface interval, how long you rest on the surface between two dives.
Safety stop: A recommended stop of 3–5 minutes at 5 m when the dive is deeper than 9 m.
Residual nitrogen: Nitrogen still stored in your body after the dive you just did. The table writes that leftover as minutes already spent at the next dive's depth.
Time left: How many minutes you may still spend on the bottom of the next dive, without decompression.
Pressure: The water pressure at that depth, in bar. It is 1 bar at the surface, and it rises by 1 bar every 10 m.
MOD: MOD stands for maximum operating depth. It is the deepest you can go on this mix before the oxygen passes the limit you set.
Best mix: The highest oxygen percent that is still inside your limit at that depth.
EAD: EAD stands for equivalent air depth. Nitrox has less nitrogen than air, so the dive is counted as shallower than the depth you actually are.

A planning aid, not a substitute for training or a dive computer.