21/05/2026
Touzil System v. 2.5 is out.
For those who don't know it: Touzil System is a free web-based tool designed for pSCR rebreather divers. It calculates Oxygen Drop and the consequent growth of inert gases at depth, mix density with reference to the Anthony/Mitchell limits, scrubber life based on diver consumption and absorbent brand and quantity, and — for cave and overhead environment diving — the rule of thirds to manage gas reserves when switching to open circuit. It runs on any device, browser-based, no installation required.
Version 2.5 adds a dedicated section for bottom gases containing Helium: enter your maximum operating depth and planned bottom time, and the system returns the recommended number of deco gases and the control average to verify at 6 metres before the final ascent.
The calculation is based on the effective Helium fraction actually breathed at depth — not the nominal mix fraction. On a pSCR, those two numbers are not the same.
Free to use. No ads.