Nitrox is the most misunderstood certification in recreational diving, and the misunderstanding is always the same.
It does not let you go deeper. It restricts how deep you can go.
Once that is clear, it becomes obvious why it is genuinely useful — and why it is arguably the best short course a Lebanese diver can take.
What nitrox actually is
Ordinary air is roughly 21% oxygen and 79% nitrogen. Enriched air nitrox increases the oxygen and correspondingly reduces the nitrogen. Common mixes are EAN32 (32% oxygen) and EAN36.
Two consequences follow, and they pull in opposite directions.
Less nitrogen means you absorb less inert gas at a given depth. That extends your no-decompression time and reduces your decompression stress.
More oxygen means you hit oxygen-related limits shallower. Oxygen becomes toxic at elevated partial pressures, which puts a hard ceiling on the depth at which a given mix can be used. The richer the mix, the shallower that ceiling.
So: longer at a given depth, but a shallower maximum depth. That is the whole trade.
Why it matters in Lebanon specifically
Look at where the diving is.
| Site | Depth |
|---|---|
| Alice B | 27–37 m |
| Shark Point | 34–38 m |
| Batroun cement wreck | 35–40 m |
| Souffleur | 38–40 m |
And note how Lebanese dive days are typically structured: a deeper wreck first, then a second dive after a surface interval.
That is precisely the profile where nitrox pays.
On the deep dive itself, at 38 metres, your bottom time is limited by gas supply as much as anything, so the no-decompression extension matters less than people expect.
On the second dive, it matters a great deal. You surface from dive one carrying substantially less nitrogen, which means a longer, more comfortable second dive and a more conservative day overall.
Across a diving holiday, over several days of repetitive diving, the cumulative effect is meaningful.
What the course involves
One of the shortest in diving.
Theory. Oxygen partial pressure, maximum operating depth, how to use nitrox tables or set a computer for the mix, oxygen exposure tracking, and the equipment considerations.
Practical. Analysing a cylinder with an oxygen analyser — you do this yourself, every time, without exception — labelling it correctly, and logging the analysis.
Dives. Many agencies do not require training dives for the entry-level nitrox certification. Some centres include them anyway, which is not a bad thing.
Typically a few hours. It can often be added to a diving weekend without costing you water time.
The rules that actually matter
The course content compresses to five habits.
- Analyse every cylinder yourself. Not the fill station's word. Not the label someone else wrote. Yours.
- Label it. Mix, maximum operating depth, your name, the date.
- Set your computer to the actual analysed mix. A computer set to air on a nitrox cylinder gives you conservative but wrong data. A computer set to nitrox on an air cylinder is dangerous.
- Know your maximum operating depth before you get in, and treat it as a hard ceiling.
- Track your oxygen exposure across repetitive dives and across days.
None of that is difficult. All of it is non-negotiable.
What nitrox does not do
Worth listing, because the marketing is sometimes vague.
It does not reduce narcosis. Nitrogen narcosis is related to depth. Some divers report feeling clearer on nitrox; the evidence for a real narcotic difference is not strong. Do not plan around it.
It does not stop decompression sickness. It reduces nitrogen loading, which reduces risk. It does not eliminate it, and it does not license a fast ascent.
It does not make you less tired. Divers often report less post-dive fatigue on nitrox. It is a widely reported subjective effect rather than a well-established one — enjoy it if you experience it, but do not buy the course for it.
It does not let you skip safety stops. Ever.
Availability in Lebanon
One practical question before booking: can your centre actually supply nitrox reliably?
Nitrox requires appropriate blending or membrane equipment and oxygen-service-clean cylinders. In a small market, availability varies by centre and sometimes by season. There is no point holding the certification if you cannot get the gas.
Ask directly: do you blend nitrox, which mixes, and is it available on the boat days I would be diving? See also regulator servicing and tank fills in Lebanon.
When to take it
After advanced training, before you start diving the deep wrecks regularly. That is the point at which it starts earning its cost.
Some agencies allow nitrox to count as one of the five adventure dives in the advanced course, which is efficient — one dive, two useful outcomes.
If you are further back on the path, the Open Water course comes first, and the full ladder is in every diving course we run.
