About SDHQ

Contact Us





















Dive Centers




Shop Online

[SportDiverHQ the complete scuba resource]

About SDHQ | Learning to Dive | Nitrox | Wreck | Deep | Cave | Deco | Eanx | HOTx | Trimix
PADI | NAUI | IANTD | Schedule | Articles | Reviews | Charts/Tables | Gallery |
Dive Centers | Destinations | Organizations | Information | Shop Online

An Introduction to Enriched Air Nitrox

Call it Oxygen Enriched Air, Enriched Air Nitrox or just plain Nitrox, this gas has taken the Sport Diving community by storm. Enriched Air Nitrox is a breathing gas consisting of air mixed with a higher percentage of oxygen. By adding additional oxygen to the mixture the rate of nitrogen absorption into the body is reduced. "Nitrox" is commonly used by recreational divers for one of two purposes: to increase the length of time one may stay at depth without requiring decompression stops and/or to reduce the risk of decompression sickness by lowering the overall nitrogen levels within the body's tissues.

A common misconception among divers is that Enriched Air Nitrox (EANx) is a deep diving gas. In fact, EANx is best applied to shallower dives. As an example of the improved bottom time one may realize by using EANx a diver making a dive to 60 feet on air has a no decompression limit of 55 minutes. In contrast, a diver making the same dive on Nitrox containing 36% oxygen would have a no decompression limit of 115 minutes. That's an hour more bottom time! (Results based on the PADI Recreational Dive Planner)

Another common use for EANx is to accelerate (shorten) the amount of time required at stops during planned stage decompression dives. By reducing the amount of nitrogen being breathed by the diver, the excess nitrogen loaded in the tissues is expelled faster. An additional benefit to the process, oxygen tends to reduce the size of any bubbles that may have formed in the divers blood stream during the ascent, reducing the odds of these "Silent bubbles" from reaching a size large enough to cause decompression sickness. Cave and technical divers using enriched air for this purpose will typically use a mix containing 40% to 100% oxygen.

NAUI Oxygen Enriched Air Nitrox Certification

This course is to provide the diver with the information necessary to utilize EANx as a breathing medium. The course may be taught as a stand-alone specialty course to certified divers or the knowledge and skills development may be integrated into the NAUI Scuba Diver course.

Academic development for this course entails reading the NAUI Nitrox Textbook, completing the review questions at the end of each chapter and attending one or more classroom sessions. The instructor classroom presentations are supported with a Power Point slide presentation. Upon completion of the academic development session(s), students are required to pass a multiple choice written exam. Students are also required to participate in a practical application workshop during which time the observe and actively analyze the oxygen content of various EANx mixes.

The NAUI Oxygen Enriched Air course requires students to complete at least two scuba dives utilizing Enriched Air. At least one of the required dives is to be a repetitive dive. Students are required to analyze their own breathing mixes and to plan and safely execute each dive.

PADI Enriched Air Nitrox Certification

The purpose of the PADI Enriched Air Diver specialty course is to familiarize divers with the procedures, safety protocols, hazards, risks, benefits and theory of no decompression diving with oxygen enriched air containing 22% to 40% oxygen. The emphasis is on diving with EAN32 and EAN36 (NOAA I and NOAA II). The course emphasizes the importance of proper procedures to ensure safety, and realistically balance the pros and cons of enriched air diving. Visiting divers can easily complete to training over a period of two days.

Academic training for this course consists of viewing PADI's Enriched Air Diver video, reading the Enriched Air Diver Manual, completion and review of Knowledge reviews and an instructor led discussion/lecture. During a practical application session students get hands on experience using oxygen analyzers and get to observe EANx tank filling procedures. Academic development ends with the successful completion of the PADI Enriched Air Diver Exam.

Upon completion of all academic requirements students will complete two dives using Enriched Air. The emphasis on these dives is on pre-dive planning and proper planning for repetitive dives when using nitrox. During the actual dives students simply take advantage of the increased no decompression limit while exploring one of North Carolina's exciting wreck diving sites.

Enrollment Form


For more information contact us via email

About SDHQ | Nitrox | Wreck | Deep
Cave | Deco | Eanx | HOTx | Trimix
PADI | NAUI | IANTD | Schedule
Articles | Reviews | Charts/Tables | Gallery |
Dive Centers | Destinations | Organizations | Information | Shop Online