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Articles on dive skills, certification, dive planning and dive sites.

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Dive DestinationsSeptember 18, 20268 min read

Best Wreck Diving Destinations in the World: Depths and Training

Chuuk Lagoon, Thistlegorm, Coolidge, Zenobia, Scapa Flow, Coron, Bikini and Gallipoli compared: depths, training needed, protection rules and wreck safety.

Dive Computers & DecompressionSeptember 16, 20268 min read

CNS Oxygen Toxicity Over Multiple Dives: A Nitrox Liveaboard Week

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.

Dive Computers & DecompressionSeptember 14, 20268 min read

Rock Bottom Gas Calculation: Minimum Gas for Two Divers, Step by Step

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.

Dive Computers & DecompressionSeptember 13, 202610 min read

Dive Computer Algorithms Explained: Bühlmann, RGBM, Gradient Factors

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.

Training & CertificationSeptember 11, 20267 min read

When to Take the Rescue Diver Course: Prerequisites and Readiness

Rescue diver prerequisites at PADI, SSI, NAUI, CMAS and BSAC, what the course covers, how long it takes, the first aid and oxygen training needed and when to start.

Safety & Dive MedicineSeptember 9, 20269 min read

PFO and Scuba Diving: Who Should Get Tested and What Comes Next

What a patent foramen ovale (PFO) means for divers: DCS risk figures, who the 2025 SPUMS/UKDMC statement says to test, and the options if you have one.

Safety & Dive MedicineSeptember 7, 20268 min read

Why Divers Get DCS Within the Limits: Data and Risk Factors

Why divers get decompression sickness inside table and computer limits: what DAN data show, the risk factors behind undeserved bends and how to lower the risk.

Safety & Dive MedicineSeptember 6, 202610 min read

Decompression Sickness Symptoms and First Aid for the Bends

Decompression sickness symptoms and when they start, how DCS differs from gas embolism, and first aid in the right order, with DAN emergency numbers.

Safety & Dive MedicineSeptember 4, 20269 min read

Nitrogen Narcosis: Symptoms and the Depth Where It Starts

Nitrogen narcosis symptoms by depth, what makes it worse, whether divers adapt, oxygen and END, and why helium is used for deep dives, with medical sources.

Dive Computers & DecompressionSeptember 2, 20268 min read

Nitrox MOD, EAD and Best Mix Calculations: Worked Examples

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.