Nitrox Analyser

Technical and cave-diving perspective

Built for the technical and cave dives I actually do.

I started building these tools because I felt there was not a solution on the market that helped me prepare safely and practically for the dives I actually do. The tools come first on this page; the technical, cave-diving, teaching, and engineering experience behind them follows afterward.

Tools for disciplined preparation

These projects support careful dive planning, gas analysis, and labelling workflows. They do not replace appropriate training, calibrated equipment, team checks, an independently verified plan, or independent gas verification.

Why I am building DivePlanner

A dive plan should let us explore what happens when the primary plan breaks.

For technical and cave dives, a depth and decompression schedule is only the starting point. I want to model the actual route, team, equipment, gases, reserves, and travel method, then ask how the whole plan changes when a critical assumption fails.

DivePlanner grows from that need. I want to compare realistic scenarios before the team enters the water: a lost DPV at the furthest point, an unavailable gas, gas sharing, different team sizes, a slower exit, or a change of route. The useful answer is not just a new runtime. It is the combined effect on travel time, gas reserves, decompression, cylinder placement, and whether the planned route still has an acceptable margin.

Scenarios I want to simulate

  • Loss or failure of a DPV at different points on an hours-long cave route
  • Complex gas scenarios: unavailable cylinders, gas sharing, bailout, and reserves
  • Route alternatives with different distances, depths, speeds, and exit times
  • Changes in team size, equipment, cylinder placement, and hand-offs
  • Combined failures, because contingencies do not always happen one at a time

Questions the plan should answer

  • Can every team member exit if powered travel becomes swimming?
  • Where does the limiting gas move when the route or speed changes?
  • How do lost gas and gas sharing change reserves and decompression?
  • Which route segments or assumptions leave too little margin?
  • What should the team brief, stage, or change before committing to the dive?
Explore DivePlanner

Gas-analysis hardware

Practical tools for gas analysis and cylinder identification.

The analyser projects make the path from a checked reading to a readable cylinder label clearer, while keeping the diver responsible for verification.

DIY Nitrox Analyser

A compact ESP32-S3 oxygen analyser with MOD calculation, a local setup interface, and direct Niimbot cylinder-label printing.

Explore the Nitrox Analyser

Trimix Analyser Connector

An external ESP32-S3 adapter that leaves the Divesoft analyser as the measurement source and turns checked O2 and helium readings into practical cylinder labels.

Explore the Trimix Connector

Why I built them

Gas logistics become a system problem on demanding dives.

From hours-long cave dives to dives deeper than 100 metres, mixed teams, and complex logistics, clear gas analysis and readable cylinder identification are not conveniences. They are part of disciplined preparation. I wanted tools I could understand, maintain, verify, and use without adding friction when a team is already managing gases, equipment, time, and task loading.

Technical and cave context

  • Long-duration and multi-stage cave dives
  • Dives deeper than 100 metres
  • Mixed-team procedures and communication
  • Multiple cylinders, gases, MODs, and hand-offs
  • High task loading before and during the dive

Engineering response

  • Keep the verified analyser reading visible as the source of truth
  • Turn checked values into clear, repeatable cylinder labels
  • Make building practical: obtain the parts, solder a few wires, and flash
  • Keep setup and maintenance understandable at user and builder level
  • Document verification steps and failure boundaries clearly

Diving and engineering background

Experience centred on technical, cave, and CCR diving.

The projects are informed by direct experience planning, supporting, and carrying out technically complex dives, backed by engineering practice and instructor experience.

Technical and cave qualifications

  • GUE Cave 2
  • GUE CCR 2+
  • GUE Tech 2+
  • More than 30 years of diving experience

Teaching and engineering

  • BSAC Open Water Instructor
  • BSAC Twinset Instructor
  • Chartered Engineer
  • Builder-focused hardware and firmware documentation