Partial Pressure Formula Explained (PSI & Bar)

[@coreybaldwin989]

And i always thought blending gases was complicated!!!! You break it down so we all can understand!

[@LakeHickoryScuba]

Glad you enjoyed the video.

[@unclemilton815]

Mate, thank you again for Part 2 Bryan. Look forward to the next one.

[@LakeHickoryScuba]

You're welcome Minton, part 3 should be published sometime today.

[@jjohn8989]

Great refresher! Looking forward to next video as most tanks are ever empty. 👍🏻

[@LakeHickoryScuba]

The next video will hopefully be published tomorrow sometime.

[@kentmartin3746]

Great video, I'm not nitrox certified, but was always curious as to the process, great explanation of the process, and how to figure the calculations. Keep up the great videos. Always like to learn the things about the processes leading up to a dive. Possible video in the future question or just comment here would be fine. On dive reels braided line or flat, why, pros and cons to the diffent types.

[@LakeHickoryScuba]

Thanks for the video idea Kent, I will see what we can do for you.

[@kevincastro2640]

Awesome! 👏👏👌

[@LakeHickoryScuba]

Thanks Kevin Castro.

[@revtechmarine]

Tech Guy at heart can't help but the open My Big Mouth awesome videos definitely look forward to the next one based on an interesting principal the calculations that your teaching today are with the basis of the tanks or pressures starting a zero which is the easiest way the calculated as you have said you're next video what's going to be about if there is some kind of blend in the tank or you're not starting from zero oddly enough just about every scuba diver is told to in there dive with some sort of gas left in the tank so when I fill station operator goes to fill it it is easier to just continue to empty the tank and start your calculation from zero but wait why then where the divers always told to end their dive with some gas remaining everyone knows but you're not supposed to empty the tank for the possibility of moisture intrusion hummmmmm.

[@LakeHickoryScuba]

Our next video in this series will be published sometime tomorrow, and yes it will be on the scenario you mentioned. A diver comes back for another fill will x-amount still in their cylinder. Not only do they want it topped off, but they also want a different blend. There are of course two options. Option one, drain the cylinder and start over from scratched, or option two, do the math and reuse the air that is left over. Stay Tuned.

[@johnb2271]

Really nice to know how they fill my nitrox tanks. When I got my nitrox rating they said that partial pressure was possibly dangerous for the operator doing the filling if the cylinder had any grease. Made sense because O2 is explosive. So if you know how much pressure to put O2 in, which you just explained, by default you know how much regular air to pump in. Why not put the regular air in first and O2 second to mitigate some of the hazzard possibility?

[@LakeHickoryScuba]

Blending Nitrox can be dangerous to the fill operator at any stage (just as anytime we deal with pure oxygen). There is a lot of trust between the fill operator and the customer. Just because a cylinder is marked oxygen cleaned, there is not a sure fire way the fill operator can be 100% certain the cylinder has remained that way since its last inspection. In regards to the order of gases (great question by the way), one of the biggest concerns is introducing contaminated air (trace amounts of hydrocarbons) back into the O2 cylinder. In the event the cylinder being filled has more pressure than what the O2 cylinder would have, then the risk of cylinder air could potentially bleed back into the oxygen cylinder. In the event the cylinder was not cleaned, then this could be an issue.

[@johnb2271]

Great answer, thanks Bryan

[@LakeHickoryScuba]

You’re welcome

[@diversdown2116]

Yep i took notes ( getting my nerd on )

[@LakeHickoryScuba]

I find myself taking notes all the time, it has sure helped me over the years remembering formulas. When it comes to math and science, I too am a nerd, and very proud of it.

[@diversdown2116]

@@LakeHickoryScuba must say thanks also watching a video on diving warms me up its -5 here 😨

[@LakeHickoryScuba]

Sounds like you may have some Ice Diving opportunities with those temperatures.

[@varazzeliguria]

in common sense I would have done so: Ean 32 .32 x 200 = 64 bar O2 Ean 21 .21 x 200 = 42 bar O2 64bar - 42bar = i must add 22 bar of O2 in an empty bottle.

[@LakeHickoryScuba]

Hello Fabian, the only step you missed would be dividing out the fraction of Nitrogen that would be mixing in once you topped of with air. This is why it is always important to follow the formula, so that we don't miss a step.