The question is, are you more likely to suffer incidences of decompression sickness (DCS) if using nitrox? Looking at the figures released by the Divers Alert Network (DAN) 2000 DAN Nitrox Workshop, no increased risk of DCS is reported when diving nitrox over air.
This is further supported by the research of Lang (2006) The State of oxygen-enriched air (nitrox) published in the Diving and Hyperbaric Medicine Journal, Volume 36, Number 2, June 2006. You can dive to about 50 metres on nitrox; naturally the oxygen percentages are somewhat leaner reducing the effectiveness yet this is still a better option than air.
Nitrogen is the limiting factor for the majority of divers, reducing nitrogen uptake increases bottom times. This can be achieved by reducing the nitrogen partial pressure which can achieved by diving shallower with air or alternatively diving to the same depth with a gas mix with reduced nitrogen. By replacing the nitrogen in the mix, bottom times are increased although oxygen is now believed to be just as narcotic as nitrogen.
Do I decrease my surface intervals on nitrox? I don't so in that respect so while the opportunity exists I never usually take it up. That being said, I don't use nitrox for shallower dives as the increased bottom times for a 18 metre dive just don't justify the extra cost.
Depending on the computer or table used, a 51 minute no-decompression limit is normal for Buehlmann tables, PADI is 56 minutes and the US Navy tables extends out to 60 minutes. Most divers have used all their gas by this stage so the values is limited, the decompression required is also negligible at any rate.
Naturally you are depth limited by nitrox, this is the whole MOD concept and if certified divers don't have either the buoyancy control then they have bigger problems than nitrox. Likewise, should they exceed their depth limits then audible and visual alarms are built into dive computers with divers setting their own PO2, I believe in personal freedom and with training, divers can make informed decisions.
Once upon a time nitrox courses required manual calculations, as nitrox use became more widespread it was found that setting a nitrox computer was sufficient, there are not too many computers produced these days that aren't nitrox capable, twenty five years ago - this wasn't the case.
With fairly extensive research done, nitrox is not considered any more dangerous than air with current computer nitrox courses concentrating on basic principles, computer use and analysing blends - a fairly straightforward course these days.
The proponents of nitrox are old school guys stuck in another era, their diving is usually limited to a single style and they don't understand nitrox themselves and don't expect you to either.
Do I decrease my surface intervals on nitrox? I don't so in that respect so while the opportunity exists I never usually take it up. That being said, I don't use nitrox for shallower dives as the increased bottom times for a 18 metre dive just don't justify the extra cost.
Depending on the computer or table used, a 51 minute no-decompression limit is normal for Buehlmann tables, PADI is 56 minutes and the US Navy tables extends out to 60 minutes. Most divers have used all their gas by this stage so the values is limited, the decompression required is also negligible at any rate.
Naturally you are depth limited by nitrox, this is the whole MOD concept and if certified divers don't have either the buoyancy control then they have bigger problems than nitrox. Likewise, should they exceed their depth limits then audible and visual alarms are built into dive computers with divers setting their own PO2, I believe in personal freedom and with training, divers can make informed decisions.
Once upon a time nitrox courses required manual calculations, as nitrox use became more widespread it was found that setting a nitrox computer was sufficient, there are not too many computers produced these days that aren't nitrox capable, twenty five years ago - this wasn't the case.
With fairly extensive research done, nitrox is not considered any more dangerous than air with current computer nitrox courses concentrating on basic principles, computer use and analysing blends - a fairly straightforward course these days.
The proponents of nitrox are old school guys stuck in another era, their diving is usually limited to a single style and they don't understand nitrox themselves and don't expect you to either.
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