Enhance Your Next Dive Holiday, Be An Enriched Air Diver.

THE QUICK ANSWER

Nitrox is most useful when the holiday includes several dives

A resort week, liveaboard or compact overseas escape can involve two, three or more dives in a day. At an appropriate depth, enriched air nitrox reduces the proportion of nitrogen in the breathing gas. That can increase the time available before reaching your no-decompression limit and can help with repetitive-dive planning.

The benefit is not automatic. Your actual dive may still be limited by gas supply, temperature, current, the group plan, the boat schedule or your own comfort. Complete the training before you travel so you can decide when nitrox is useful, analyse the cylinder and use the mix within its oxygen limits.

START WITH THE GAS

What is enriched air nitrox?

Ordinary compressed air contains about 21% oxygen and 79% nitrogen. Enriched air nitrox—also called EANx or simply nitrox—contains a higher percentage of oxygen and therefore a lower percentage of nitrogen. Common recreational mixes include EAN32 and EAN36; the number describes the measured oxygen percentage.

Less nitrogen at the same depth and for the same time can mean less nitrogen uptake than on air. That is why nitrox can offer a longer no-decompression limit on suitable profiles. The extra oxygen also creates an important limit of its own, so the gas must be matched to the planned maximum depth.

Consideration	Air	Enriched air nitrox
Oxygen content	About 21%	More than 21%; EAN32 and EAN36 are common
Nitrogen exposure	Baseline for the same depth and time	Lower for the same depth and time
No-decompression time	Calculated using the air setting or air tables	Often longer at suitable depths, but not on every dive
Depth planning	Limited by training, conditions and the dive plan	Also limited by the analysed mix’s maximum operating depth
Before the dive	Complete normal gas and equipment checks	Personally analyse and record the mix, then set the computer correctly

CLEAR EXPECTATIONS

What nitrox can—and cannot—do

Nitrox can

reduce nitrogen exposure compared with air on the same dive profile;
increase the no-decompression limit at suitable depths;
support more flexible planning across repetitive dive days; and
let you keep some of the additional no-stop time as a conservative margin rather than use all of it.

Nitrox cannot

allow you to dive deeper than air;
remove the risk of decompression sickness or oxygen toxicity;
guarantee a longer dive or a shorter boat schedule; or
replace controlled ascents, appropriate surface intervals, good judgement or formal training.

THE DEPTH LIMIT THAT MATTERS

More oxygen means a shallower maximum operating depth

As depth increases, the partial pressure of oxygen increases. Each nitrox mix therefore has a maximum operating depth (MOD) based on the analysed oxygen percentage and the planned maximum partial pressure of oxygen. Going beyond that MOD raises the risk of central nervous system oxygen toxicity, which can include a seizure underwater. Cumulative oxygen exposure is a separate limit that must also be tracked.

The right question is not “How deep can nitrox take me?” It is “Which mix is appropriate for the maximum depth of this dive?” Your enriched air training teaches you how to answer that question, confirm the result and stay within the planned limit.

Remember

Analyse the gas.
Know the MOD.
Respect the limit.

BEFORE EVERY NITROX DIVE

Four checks turn the cylinder label into a real dive plan

Personally analyse the cylinder

Confirm the oxygen percentage with a suitable analyser rather than relying only on what was requested or written on the cylinder.
Record and identify the fill

Follow your training and the operator’s procedure for recording the analysed percentage, MOD, date and diver identification.
Set the dive computer

Enter the measured oxygen percentage and confirm the relevant oxygen settings before the dive. Never assume yesterday’s setting is still correct.
Match the mix to the dive

Confirm that the planned maximum depth remains within the mix’s MOD and that the profile stays within the applicable oxygen and no-decompression limits.

USE THE COMPUTER YOU UNDERSTAND

Get your dive computer ready before the trip

Most current recreational dive computers support nitrox, but menus, oxygen settings, alarms and lockout behaviour vary. Learn how your own model displays the gas mix, MOD, no-decompression time, oxygen exposure and surface interval before you are on a moving boat.

Use one computer throughout the dive day because it tracks your individual depth, time and surface-interval history. Do not share a computer or swap to another diver’s unit and treat its limits as your own. Bring the charger, cable or approved spare battery that your model requires.

Browse nitrox-capable dive computers →

TRAIN BEFORE YOU TRAVEL

What the PADI Enriched Air Diver course covers

Abyss’s current course combines online knowledge development with an instructor-led practical session. You learn how oxygen percentage changes the dive plan, how to analyse and record a fill, how to set a nitrox-compatible computer and how to respect maximum operating depth and oxygen-exposure limits.

Online learning

Allow approximately two to four hours for the theory and knowledge development.

Practical session

Analyse a cylinder, record and identify the fill, and configure a dive computer with your instructor.

Optional ocean dives

Two open-water dives can be added for in-water practice; the current course page states that an additional fee applies.

Entry requirements

Minimum age 12, with PADI Open Water Diver, Junior Open Water Diver or an accepted equivalent certification.

Course formats, fees, dates and availability can change. Check the live course page before booking.

View current course details and dates Ask the Abyss team a question

MAKE IT USEFUL ON HOLIDAY

Plan the nitrox details before departure

Certification gives you the skills; the operator determines what is actually available. Before paying for a trip, ask whether nitrox is offered, which mixes are normally supplied, whether it costs extra and whether the itinerary includes depths where that mix is appropriate.

Carry proof of certification. Download an offline copy if phone coverage may be limited.
Confirm the fill procedure. Find out where and when guests analyse and label cylinders.
Check the planned depths. Nitrox may be valuable on moderate-depth repetitive dives and unsuitable for a deeper site if the offered mix’s MOD is too shallow.
Keep ordinary limits in place. Nitrox does not justify rapid ascents, skipped surface intervals or flying sooner after diving.
Pack for your computer. Bring its charger, cable or approved battery kit and know how to use the unit without an internet connection.

Use the Abyss Dive Travel Hub to compare current departures, or explore the current Vanuatu dive-trip options. Open the exact trip page to confirm current eligibility, inclusions, nitrox availability and booking terms.

WATCH THE COURSE OVERVIEW

See what enriched air training is designed to teach

This PADI overview introduces the purpose of the Enriched Air Diver specialty. Use it as an introduction; complete the required training before diving with nitrox.

COMMON QUESTIONS

Enriched air nitrox FAQ

Does nitrox let me dive deeper?

No. A higher oxygen percentage normally gives the mix a shallower maximum operating depth. Choose a mix that is appropriate for the planned maximum depth and stay within the MOD taught in your training.

Will every nitrox dive be longer?

No. Nitrox may extend the no-decompression limit at a suitable depth, but gas consumption, conditions, temperature, the group plan or the operator’s schedule may end the dive first.

Is nitrox automatically safer than air?

No breathing gas makes a dive automatically safe. Nitrox can reduce nitrogen exposure on the same profile, but it introduces mix-specific oxygen limits and does not remove decompression-sickness risk. It must be analysed, planned and used correctly.

Will nitrox make me feel less tired?

Some divers report less post-dive fatigue, but research has not established this as a reliable benefit. Do not use how you expect to feel as a reason to extend a dive or reduce normal recovery time.

Can I fly sooner after diving with nitrox?

Do not assume so. Follow the current flying-after-diving guidance from your training organisation, dive operator and dive computer, and build an appropriate no-fly interval into the itinerary.

GET NITROX-READY

Learn the procedures before your next multi-day dive trip

Build the practical skills to analyse your gas, identify its maximum operating depth and set your dive computer correctly—then arrive on holiday ready to use nitrox when it suits the plan.

Explore Enriched Air Diver Browse dive holidays

Safety references

Last reviewed August 2026 against the current Abyss course information and guidance from recognised diver-training and safety organisations.

This article provides general information and is not a substitute for certification, an instructor’s guidance, the dive operator’s procedures or the instructions for your equipment.

Why Learn Enriched Air Nitrox Before Your Next Dive Holiday?