Guides
A dive computer tracks nitrogen for you, but you still need to know what its numbers mean. These guides cover no-decompression limits, how algorithms differ, nitrox and planning gas for a dive.
Where an article uses a formula, you can check the result with the calculators on this site.
Dive Computers & Decompression10 min read
What a dive table is, how to read one step by step, and how the PADI RDP, US Navy, DECO 2000, BSAC 88 and NAUI tables compare on air at 18 m (60 ft).
Read moreDive Computers & Decompression9 min read
Trimix vs heliox: what each gas contains, why tech divers keep some nitrogen, why saturation divers breathe heliox, and END and ppO2 worked out at 60 m.
Read moreDive Computers & Decompression7 min read
Where the Depth app and Oceanic+ save Apple Watch Ultra dives, what each log records, how to export dives as UDDF files and how to get a watch dive signed.
Read moreDive Computers & Decompression9 min read
Which Suunto computers run Fused RGBM 2, Bühlmann 16 GF or both, how to switch, what each changes, and no-stop times at Suunto's gradient factor presets.
Read moreDive Computers & Decompression10 min read
What the conservatism setting changes on Shearwater, Suunto, Garmin, Mares, Scubapro, Cressi, Aqua Lung and Oceanic computers, with no-stop times per level.
Read moreDive Computers & Decompression11 min read
What a decompression plan is built from, what each gradient factor changes, where deco gas switches happen, and the stop schedules for one 40 m dive.
Read moreDive Computers & Decompression10 min read
How dive shops make nitrox: partial pressure blending, stick blending, membranes and pre-mixed banks, with worked fills in bar and the oxygen cleaning rules.
Read moreDive Computers & Decompression11 min read
Why helium replaces nitrogen at depth, how equivalent narcotic depth is calculated two different ways, and how to pick a trimix mix with worked numbers.
Read moreDive Computers & Decompression11 min read
How to plan a mountain lake dive: where altitude rules start, Cross-corrected tables, dive computer settings, the wait after driving up and the trip home.
Read moreDive Computers & Decompression8 min read
CNS % and OTU explained with a worked four-dive EAN32 day, NOAA single and 24-hour limits, REPEX multi-day OTU limits and the symptoms to know on a liveaboard.
Read moreDive Computers & Decompression8 min read
How to calculate rock bottom (minimum gas) for two divers sharing one tank: a worked 30 m example, how it compares with thirds and 50 bar, and turn pressures.
Read moreDive Computers & Decompression10 min read
How dive computer algorithms work: tissue compartments, M-values, Bühlmann vs RGBM, gradient factors like 30/70 vs 40/85, and why two computers disagree.
Read moreDive Computers & Decompression8 min read
Step-by-step nitrox MOD at 1.4 and 1.6 bar, EAD checked against an air table, best mix for a planned depth, and how to analyse and label a tank.
Read moreDive Computers & Decompression8 min read
NOAA no-stop limits on air, EAN32 and EAN36 at 12-33 m, what the fatigue studies found, what nitrox costs, and the dives where it adds nothing.
Read moreDive Computers & Decompression7 min read
A worked SAC rate example from a logged dive, what the number is for, and the measured effects of workload, cold, stress, trim and weighting on your air use.
Read moreDive Computers & Decompression8 min read
How long to wait between dives: surface intervals on the DECO 2000 table, group letters and residual nitrogen time, with a worked two-dive day.
Read moreDive Computers & Decompression8 min read
Read Dr. Max Hahn's DECO 2000 table step by step: round depth and time up, find the no-stop limit, stops and group letter, then follow one worked dive.
Read moreDive Computers & Decompression8 min read
Apple rates the Watch Ultra for recreational dives to 40 m, but only an app like Oceanic+ makes it a dive computer. Specs, paid plans, gases and limits.
Read moreDive Computers & Decompression8 min read
Dive computer died mid-dive? End the dive and ascend with your buddy at 9 m/min, then check how long to stay dry. Steps from makers and DAN, plus backups.
Read moreDive Computers & Decompression8 min read
Air-integrated dive computer vs SPG: how hoseless transmitters work, how makers calculate gas time remaining, what happens on signal loss, and the real cost.
Read moreDive Computers & Decompression9 min read
Choosing a dive computer as a beginner: a readable screen, conservatism settings, nitrox, air integration, battery, lockouts and price tiers, as a checklist.
Read moreDive Computers & Decompression7 min read
A 12 L tank at 200 bar lasts a 20 L/min diver about 45 min at 10 m, 32 at 18 m and 22 at 30 m. AL80 figures, SAC rates and why the reserve comes first.
Read moreDive Computers & Decompression10 min read
NDL means no-decompression limit, the longest time at a depth with no required stops. No-stop tables for 12-42 m and 40-140 ft from DECO 2000 and US Navy.
Read moreDive Computers & Decompression9 min read
What Doppler studies show about safety stops, what PADI, BSAC, VDST and dive computers recommend, the NEDU deep stop result, and how to hold a stop in current.
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