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Decompression models: what is the difference between Bühlmann and bubble models? What does your dive computer calculate and how?

Sunday

11:00

Stage 3

This is what you can expect

How come my computer shows a different 0-time or deco times than my buddy? Apart from the known factors (buddy has dived a bit deeper or has already made a morning dive) it is possible that the computers use a completely different calculation model. There are roughly 2 types of deco models: dissolved gas models (such as the Bühlmann model and all its variants) and bubble models (for example RGBM, VPM and others). These calculate your deco time or 0-time in a fundamentally different way. This leads to different values with longer or shorter 0-times and deeper or shallower stops. In this presentation Bas explains what the differences are and how these computers arrive at their results.

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Bas Poelmann

Bas learned to dive in 1993 at NOB association Calypso in Leiden and became a PADI instructor in 2001. Since 2012, Bas has only given technical diving courses. First via NAUI and since 2019 via TDI. He has dived all over the world, from the Dutch North Sea, Scotland, Norway, Croatia, Malta, Greece, Turkey, Philippines, Bali, Malaysian Borneo, Truk Lagoon, Italy, Indonesia etc. Bas is a TDI Full trimix instructor and MOD 3 diver at the JJCCR and owner of Black Marlin Technical Dive Training. Bas is often asked to speak at Duikvaker, DuikenInBeeld, Wij Duiken Veilig, DiveExpo and Baltic Tech. In addition to diving, he is a consultant/trainer crisis management and instructor survival at sea. Bas can be found at Duikvaker at the Scuba Academy stand