Enriched Air - Diving with Nitrox

Extend Dive TImes Well known as PADI's most popular specialty course, it is still common for new divers to wonder what are the advantages to scuba diving with enriched air nitrox?  The simple answer is that in most cases a diver can stay down longer, and experience shorter surface intervals using enriched air.  For those reasons alone, Enriched Air Diver is often the first specialty course taken by new divers.  However, there are several other benefits to diving with enriched air nitrox.

1. More Time to Explore: It's why we dive!  Longer bottom times are possible because  the reduced percentage of nitrogen in enriched air nitrox allows divers to extend their no-decompression limits (dive time) by reducing nitrogen absorption. Recreational enriched air nitrox (21-40% oxygen) contains a lower percentage of nitrogen than air.

Here's a simple comparison. Two divers set off to explore a wreck in 90 feet of sea water.  Diver A is using a standard tank of air.  Diver B is using an enriched air gas mixture of 36% oxygen and 64% nitrogen.  According to the NOAA (National Oceanographic and Atmospheric Association) no-decompression dive tables, Diver A may stay only a maximum of 30 minutes at this depth.  Diver B has up to 20 minutes longer (a total of 50 minutes) diving with the enriched air nitrox 36 mixture.

Enriched air nitrox can have a huge effect on allowed bottom time, even doubling it under the right circumstances.

2. Less Time Between Dives: Surface Intervals, the time a diver remains out of the water between dives, are taken so that the nitrogen absorbed during the first dive may off-gas (be released from a diver's body). A diver has less nitrogen in his body at the end of a surface interval than at the beginning of it. A diver using enriched air nitrox absorbs less nitrogen for a given depth and dive time than a diver using air. This means that the diver using enriched air nitrox has less nitrogen to off-gas during a surface interval, which can shorten the required surface interval time.

3. Extended Repetitive Dive Times:  A diver using an enriched air nitrox mix absorbs less nitrogen. In addition to the benefits outlined above, a diver using enriched air will benefit from longer allowable bottom time on a repetitive dive than a diver using air.

More diving, less waiting between dives, a richer experience!  No wonder the enriched air specialty is so popular! It is also a classroom-based specialty, and may be obtained through e-learning and an evening Practical Application Class at Seal Sports.

Diving with enriched air nitrox benefits all types of diving, but it goes especially well with these specialties:

  • PADI Wreck Diver course – Popular wrecks tend to be deeper, so enriched air nitrox maximizes your exploration time.
  • PADI Deep Diver course – The deeper you dive, the shorter your no stop time – but enriched air nitrox increases it, giving your more time at depth
  • PADI Digital Underwater Photographer – Photographers usually like to make several dives so they can get lots of pictures. Enriched air nitrox reduces the amount of residual nitrogen you accumulate, allowing repetitive dives to be longer.
  • PADI Master Scuba Diver - The PADI Enriched Air Diver course counts toward your Master Scuba Diver rating -- the highest non professional rating in recreational diving.

And for those divers ready to experience Rebreather diving, the Enriched Air Specialty is a required prerequisite.  Seal Sports offers an enriched air course each month. Check out our calendar or give us call at 985-674-3088.