Nitrox

PADI Enriched Air Specialty

Minimum age: 15

Minimum qualification: PADI Open Water Diver

Enriched Air analyserThe PADI Enriched Air (Nitrox) Specialty, or as it’s more commonly known the Nitrox course, is the subject of more urban myths than the Yeti, or puma sightings in Dorset. Let’s scotch the two biggest now. Nitrox will not allow you to dive deeper or give you more air. Clear? Now you’re confused aren’t you? Nitrox in this context is a mix of gas that contains between 22% and 40% oxygen. What this does is to extend your no decompression limit (NDL) beyond what diving on air would allow you to do.

Remember your Open Water Course tables? No I didn’t think so. Well dust them down and check them out. Your NDL for 30mtrs diving on air is 20 minutes. If you raise the oxygen in the mix up to 32% or 36% for example, then your NDL is extended to 30 and 35 minutes respectively. That’s quite a difference isn’t it? However, the maximum depth that you can dive to on those two mixes is 33 and 29mtrs respectively as opposed to 56m on plain old air.

This means that although you can stay down longer on Nitrox, assuming you have sufficient air, you can’t go as deep. The benefit to us as divers is that at shallower depths we are breathing reduced amounts of nitrogen. That pays dividends on repeated dives over multiple days such as on a diving holiday, and nowadays lots of overseas diving operators offer free Nitrox when you dive with them.

This is a very popular course and understandably so.

Nearly all regular divers both here and overseas dive on Nitrox to varying degrees and without doubt, it’s a major bonus whatever your current qualification. The course is classroom based learning how to decide your optimum gas mix, how to analyse it as well as how to use the tables required in order to dive safely.

No qualifying dives are required so you can have one day in the class and then use the gas the next day on holiday.