TDI Nitrox

Standard nitrox certification qualifies you to dive enriched air up to 40% oxygen, extending your no-decompression limits meaningfully beyond what air allows. TDI Nitrox Diver is the entry-level course that gets you there. It covers mixtures from EAN-22 through EAN-40, the gas planning and equivalent air depth (EAD) calculations that come with them, and the equipment and analysis procedures every nitrox diver needs. It's a knowledge-based course, no additional open water dives are required beyond what you already hold, which makes it one of the fastest certifications to add to your card. TDI Nitrox is also the entry point into the wider TDI technical track: it's the prerequisite for Advanced Nitrox, Decompression Procedures, and Semi-Closed Rebreather training.

Who This Course Is For

• The certified open water diver who wants to extend bottom time using enriched air nitrox
• Divers curious about the benefits and hazards of nitrox as a breathing gas and want to understand the physiology behind it
• Divers considering the move toward technical diving education, since Nitrox is a required first step

What the Course Covers

Benefits, Hazards, and Nitrox Physiology

Nitrox extends no-decompression limits by reducing the nitrogen content of your breathing gas, but that comes with oxygen toxicity considerations that don't exist when diving air. The course covers oxygen exposure limits, the physiology behind them, and how to work within safe limits for mixes from 22% through 40% oxygen. Understanding where those limits sit is the foundation for every other decision the course covers.

Gas Planning and EAD Calculations

Diving nitrox means calculating equivalent air depth (EAD) to know your actual decompression status at a given depth and gas mix. The course covers EAD calculations by hand and with tables, dive computer use for nitrox, and how to plan a dive around a specific mix rather than defaulting to a standard air profile.

Equipment, Cylinder Labeling, and Gas Analysis

Nitrox cylinders require correct labeling, and using the wrong gear or an unverified mix creates real risk. The course covers proper cylinder labeling for nitrox, how to analyze a gas mix with an oxygen analyzer before every dive, and an introduction to gas blending procedures. Analyzing your own gas before every dive is the habit this course is built to instill.

Course Format

TDI Nitrox has no open water dive requirement. It's completed through classroom study or eLearning, a hands-on oxygen analysis exercise, and a written exam. That makes it one of the quickest certifications to add, and a natural companion to another course you're already scheduling.

[H2] What Nitrox Unlocks

Completing TDI Nitrox qualifies you to:

• Dive using enriched air mixes from EAN-22 through EAN-40 without direct supervision
• Enroll in TDI Advanced Nitrox
• Enroll in TDI Decompression Procedures
• Enroll in TDI Semi-Closed Rebreather courses

For most divers, Nitrox is the natural first step beyond recreational certification, extending your bottom time now, and setting up everything that follows if you decide to go further into the technical track. Call us at (480) 881-4013 if you want to talk about where this fits into a longer-term training plan.

Who Can Enroll

The TDI Nitrox course is open to certified Open Water Divers or those currently enrolled in an Open Water Diver course. Additional requirements:

• Minimum age 15 with parental consent, 18 without

Gear and Equipment

No additional gear is required beyond your existing open water setup. If you're planning to continue toward Advanced Nitrox or the wider technical track, gear requirements change, stop by the shop and we can help you plan ahead. All students enrolled in a course receive a discount on purchases during enrollment.

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Frequently Asked Questions

What is TDI Nitrox?

TDI Nitrox Diver is the entry-level certification that qualifies divers to use enriched air nitrox mixes from EAN-22 through EAN-40 to extend no-decompression limits. It covers the benefits and hazards of nitrox, oxygen exposure limits, EAD calculations, cylinder labeling, and gas analysis procedures. It's also the prerequisite for TDI Advanced Nitrox, Decompression Procedures, and Semi-Closed Rebreather training.

What is the difference between TDI Nitrox and TDI Advanced Nitrox?

Standard TDI Nitrox covers enriched air mixes up to 40% oxygen for recreational no-decompression diving. TDI Advanced Nitrox covers everything above that threshold, gas mixes up to 100% oxygen, the physiology of oxygen toxicity at higher percentages, and the equipment requirements specific to high-O2 gases. Nitrox is the prerequisite you need before enrolling in Advanced Nitrox.

Do I need to complete open water dives for this course?

No. TDI Nitrox is a knowledge-development course completed through classroom study or eLearning, an oxygen analysis exercise, and a written exam. There's no open water diving requirement, which is part of why it's one of the quickest certifications to add.

What can I dive after certifying?

After completing TDI Nitrox, you're qualified to dive using enriched air mixes from EAN-22 through EAN-40 without direct supervision.

What courses does Nitrox unlock?

TDI Nitrox is the prerequisite for TDI Advanced Nitrox, TDI Decompression Procedures, and TDI Semi-Closed Rebreather courses. Call us at (480) 881-4013 if you want to talk through how Nitrox fits into a longer training plan.

Ready to Extend Your Bottom Time?

Contact us to schedule the TDI Nitrox course. Call us at (480) 881-4013 or stop by the shop. We are open Monday through Saturday 11am to 6pm and Sunday 11am to 5pm, at 18618 S 186th Way, Queen Creek, inside The Shooting Range.

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