>How about 40 percent oxygen and 60 percent nitrogen? (Note: This is real stuff, >it's called Nitrox.)
As a nitrox certified diver I can offer that most common nitrox mixes do not exceed 34% oxygen and often are 32% oxygen. For safety, a diver with 32% oxygen is typically limited to about 112 feet water depth, before potential oxygen toxicity sets in to the nervous system.
For safety a diver with 36% oxygen is limited to about 95 feet water depth.
A large majority of underwater reefs around the world are above these maximum nitrox depths.
Furthermore, nitrox is quite popular, especially among older divers as many seem to agree they have more energy near the end of a 2 tank or multiple tank dive day.
Using plain air and 2 tanks or more dives per day, it's been common to come back to the hotel and fall asleep to get a rest (or similar on liveaboards).
But using nitrox on all dives it's common for even the older crowd to have enough energy to be ready to go downtown to the bars and have some drinks after a day of diving.
> As a nitrox certified diver I can offer that most common nitrox mixes do not exceed 34%
You're right. I have never practically seen a Nitrox mixture with 40% oxygen. 28% would be far more typical. Mostly I dived with mixtures around 32%.
For wild and wonderful reasons, however, my SSI Nitrox certification allows mixtures of up to 40%. This would allow a maximum operating depth of 25 meters (30 meters if you stretch the safety margin), which is not very much when you go - for example - wreck diving at a lot of places.
I think thermal insulation plays a FAR bigger role in how tired one feels. I wear 7mm wetsuit even in tropical waters. All the “tough guys” make fun of me for it, but I’ll do five 1-hour dives a day on a live aboard trip while they get in two or three 1/2-hour dives. Even in 85 degree water, your body gets cold fast.
>Furthermore, nitrox is quite popular, especially among older divers as many seem to agree they have more energy near the end of a 2 tank or multiple tank dive day.
Anecdotally, Nitrox is supposedly good for hangovers.
>How about 40 percent oxygen and 60 percent nitrogen? (Note: This is real stuff, >it's called Nitrox.)
As a nitrox certified diver I can offer that most common nitrox mixes do not exceed 34% oxygen and often are 32% oxygen. For safety, a diver with 32% oxygen is typically limited to about 112 feet water depth, before potential oxygen toxicity sets in to the nervous system.
For safety a diver with 36% oxygen is limited to about 95 feet water depth.
A large majority of underwater reefs around the world are above these maximum nitrox depths.
Furthermore, nitrox is quite popular, especially among older divers as many seem to agree they have more energy near the end of a 2 tank or multiple tank dive day.
Using plain air and 2 tanks or more dives per day, it's been common to come back to the hotel and fall asleep to get a rest (or similar on liveaboards).
But using nitrox on all dives it's common for even the older crowd to have enough energy to be ready to go downtown to the bars and have some drinks after a day of diving.