DIR- Generic Why use GUE nitrox only

[jadairiii]

Like most shops, Extreme Exposure's primary market is the people diving nearby, and for the people diving nearby, EANx 32 is ideal. I can't imagine why I would ever go into Extreme Exposure and ask for air. In contrast, people diving nearby where I live in Colorado have little to no need for nitrox, so most shops don't even have the ability to make it. Until I retired from instruction, the shop I used could only get nitrox when I made it for them, using all my own equipment.

.....refilling tanks for the next dives required us to bleed out much of the remaining gases in order to get the tank levels low enough be able to transfill from the supply bottles without a booster. We sent thousands of cubic feet of expensive helium into the stratosphere because of that.....When I finally got a booster (electric),

That was the beauty of Fill Express in Pompano, you could just top off what ever you wanted. Problem with Fill Express, if you left your tanks, no telling what you would have in them when you picked them up! You had to stand there and tell them what you needed.

 

[crofrog]

In contrast, people diving nearby where I live in Colorado have little to no need for nitrox, so most shops don't even have the ability to make it.

I think at altitude there is even more a reason to lower your risk by using 32...

 

[boulderjohn]

I think at altitude there is even more a reason to lower your risk by using 32...

In Colorado, the deepest water you will find easily for diving is about 35 feet. One of the two most popular diving spots has a maximum depth of 21 feet. A lot of people do not see DCS as a significant threat at those depths.

For deeper diving requiring nitrox or trimix, we go to New Mexico, about a 400 mile trip from the Denver area. The site most people dive there is about 80 feet deep. The site calling for trimix is about 280 feet deep, but very few people have access to it.

 

[sparragus]

The site calling for nitrox is about 280 feet deep but few people have access to it.

Did you mean trimix?

 

[boulderjohn]

Did you mean trimix?

yep--I'll fix it.

 

[DeepSeaExplorer]

It’s not as much of an issue with shallow dives, but the major benefit of standardized gasses is everyone having similar deco schedules/runtimes.

I’ve been a boat where 10 divers have four different gas mixes between them. Some are doing best mix, some have a standardized mix, and somebody’s got something weird because they topped off tanks they used on their last dive. (I’ve done it many times myself) So everyone’s doing different deco schedules and not staying together. Boat Capt wants to know the runtime, and it’s a mess.

I’ve seen divers completely wiped out after a dive because they used the wrong mix. It used to be common to see divers passed out on the boat after the dive. Standard gas mixes changed that.

There’s also some institutional learning going on too. On a dive to 180fsw, I was diving 21/35 and felt a little loopy. Other divers noticed it too. Now the recommended gas for 180fsw is 18/45. Not because of the PO2, but because 35% wasn’t enough Helium for 180fsw. There’s more to standardized gas mixes than just PO2.

 

[boulderjohn]

So everyone’s doing different deco schedules and not staying together. Boat Capt wants to know the runtime, and it’s a mess.

Why is it a mess? I have been on many such boats. The DM asks for the run times. People tell them. Then they do the dives. If my group's plan is different from another group's, what's the problem?

I’ve seen divers completely wiped out after a dive because they used the wrong mix. It used to be common to see divers passed out on the boat after the dive. Standard gas mixes changed that.

I have no idea what you mean by using the "wrong mix" and being wiped out. I have never seen divers passed out on the boat after a dive because they used the wrong mix. I have never even heard of it until now.

If you have trimix training, you should know the range of acceptable mixes for the dive you plan to do, and you should be able to plan the dive accordingly. Any mix in that range should be safe.

 

[OrcasC205]

So they don't have to "school" folks like the OP on this post for coming to their shop and simply asking for an air fill.

There is no revenue in "schooling" someone to not get the gas they ask for. Dive shops are for profit businesses and often are affiliated with more than one training agency (e.g. GUE and NAUI.)

 

[crofrog]

In Colorado, the deepest water you will find easily for diving is about 35 feet. One of the two most popular diving spots has a maximum depth of 21 feet. A lot of people do not see DCS as a significant threat at those depths.

Sure they made consider the risk acceptable, but I think this is one area where it's pretty easy to unequivocally say nitrox 32% has a lower absolute risk compared to air.

Is there a practical difference, maybe not, but there is an absolute difference.

 

[grf88]

I think anyone going deeper that 100ft. should be using readily available trimix. After all it hardly makes any difference to the cost.