EnviroDive wrote the book on gas blending...The PADI/DSAT book!

As the diving depths are relatively shallow (to 90 feet), these working divers are the perfect candidates for using oxygen enriched air.

Using oxygen enriched air with this group of divers presents its own set of unique problems. Traditional enriched air Nitrox training does not meet their needs.

It was while researching the solutions for fish farmers that this oxygen enriched air program was developed.

If you trace the history of oxygen enriched air, you will find that all present training is based on stringently supervised scientific and military divers, primarily using surface supplied full-face masks or helmets. If these divers had a seizure, brought on by elevated oxygen concentrations at depth, they would survive. Unfortunately a convulsing SCUBA diver would lose their regulator mouthpiece and most likely drown.

While pondering alternatives to standard oxygen enriched air training, I consulted with David Johnstone, a former Canadian Navy clearance diver, commercial diver, and perhaps one of the best "minds" in the scuba diving industry. David suggested that by keeping the oxygen concentrations low on the deeper scuba dives, it would eliminate the risk of an oxygen toxicity event, which is the only additional risk that using oxygen enriched air poses. His simple solution made sense.

Using David's concept as the cornerstone, it was relatively straightforward to design an easy to use "oxygen enriched air table" that negates the need for the diver to remember six math formulas.

The final stumbling block was how to develop a simple way to track the total accumulated oxygen exposure. This is very similar to tracking nitrogen exposure for repetitive dives when using air tables. My editor, SueLynn Bjorkman, came up with the concept of colour coding the new table to reflect total oxygen exposure limits. Simple and brilliant.

Those of us that are safely diving using oxygen enriched air can be thankful to these two "thinkers".

This Certification Course Includes:

Introduction

Chapter 1 - Physiology

• Decompression Illness (DCI)
• Arterial Gas Embolism (AGE)

Chapter 2 - Physics

• Fraction of Gas (Fg)
• Equivalent Air Depth (EAD)
• Partial Pressure of a Gas (Pg)

Chapter 3 - Repetitive Oxygen Enriched Air Dives

Chapter 4 - Technical information

• Tank Identification
• Oxygen Analysis
• Special Equipment Requirements
• Oxygen Service
• Gas Blending
• Fill Log

Chapter 5 - Workbook

Appendix I - Answers to Review Questions

Appendix II - EnviroDive OEA Table (DCIEM)

Appendix III - DCIEM Air Dive Tables

Appendix IV - Resources

Bibliography

DCIEM Repetitive Dive Worksheet