Nitrox course. What's the point?

[lermontov]

The advantage to the triangle is that it is 3 equations in one easy-to-remember format. It does require an extra step (converting pressure to depth), but the easy-to-remember aspect trumps that defect.

im with you - I cant see how this can be any simpler to remember -the only thing I do is write ATA instead of P.

For many people when they see a maths equation their eyes glaze over. When I talk to people who are going to do a nitrox/deco course I advise them to learn and understand Daltons T until it's ingrained . Its one thing you will use over and over again right through to advanced diving

 

[Manatee Diver]

For many people when they see a maths equation their eyes glaze over. When I talk to people who are going to do a nitrox/deco course I advise them to learn and understand Daltons T until it's ingrained . Its one thing you will use over and over again right through to advanced diving

Unless you decide to go for standard gases, then you just need to know your max depth and select the gas appropriate for that depth.

 

[EFX]

Right but the computer doesn't know that you are at 115 feet, it knows that you are at 4.5 ATA, and then it converts that to feet based on what you set it to (fresh or salt water). So you are determining whether or not you get a warning based on whether or not you set that toggle. It should give you the warning at the same ambient pressure, no matter what you are diving in, or no matter how many actual feet there are between you an the surface.

The computer actually gives you a warning at the same ambient pressure as long as you set it for fresh or salt water. Why? I think you mentioned it already. Salt water is denser and therefore a column of salt water weighs more than an equal column of fresh water. Hence, at the same depth the pressure will be different. An automatic way of compensating for this is if the computer also had a sensor to distinguish salt water from fresh water.

 

[rick00001967]

An automatic way of compensating for this is if the computer also had a sensor to distinguish salt water from fresh water.

some computers can do this ?

 

[Bigbella]

In past threads, most people say a good way to see the difference is a week of diving on a liveaboard.

When the shop that I worked for, first offered nitrox, back then, all of us were using it almost exclusively, since we were not charged at the time; and when I did stints on live-aboards, often did the same.

Didn't notice anything.

The only guy who claimed any difference, at that time, was a co-worker, the size of a Buick . . .

 

[Dody]

Original Post or Original Poster depending upon the context.

Thanks. I thought that it was either newbie or operator . SB is the first american forum I am in.

 

[EFX]

An automatic way of compensating for this is if the computer also had a sensor to distinguish salt water from fresh water.

some computers can do this ?

Not that I know of. An additional sensor adds more cost and another failure point. It's easier to enter salt or fresh water. We already enter in ppO2, fO2, last stop depth, minutes at the safety stop (some computers). On my Shearwater Perdix I can enter EN13319 and forget about setting water type again unless I want a more accurate depth reading. This setting interpolates the water pressure between fresh and salt to provide a depth reading midway. 1 atm (atmosphere gauge) of water pressure is equal to 33 ft of sea water or 34 ft of fresh water, so we're not talking about much difference in depth.

 

[boulderjohn]

Right but the computer doesn't know that you are at 115 feet, it knows that you are at 4.5 ATA, and then it converts that to feet based on what you set it to (fresh or salt water). So you are determining whether or not you get a warning based on whether or not you set that toggle. It should give you the warning at the same ambient pressure, no matter what you are diving in, or no matter how many actual feet there are between you an the surface.

That's exactly what it does. If my computer is set to warn me that my partial pressure of oxygen has exceeded 1.6, it will do that when the partial pressure exceeds 1.6. Period.

If I am diving 50% nitrox in the ocean, that will be at about 70 feet (not exactly). If I am diving in the lake where I dive at altitude, it will do that at about 80 feet (not exactly).

 

[Blackcrusader]

When the shop that I worked for, first offered nitrox, back then, all of us were using it almost exclusively, since we were not charged at the time; and when I did stints on live-aboards, often did the same.

Didn't notice anything. The only guy who claimed any difference, at that time, was a co-worker, the size of a Buick . . .

I do dive vacations where I do 35 - 40 dives in two weeks so 3 or 4 dives a day. I dive mainly on air. One vacation I dove on Nitrox and I did not feel any different.

 

[Dody]

I do dive vacations where I do 35 - 40 dives in two weeks so 3 or 4 dives a day. I dive mainly on air. One vacation I dove on Nitrox and I did not feel any different.

Interesting. So, it is possible to safely do 4 dives a day on air.?