How to CORRECTLY check your NITROX mix 🤓🤓 ¦ UKDiver

[@Hoveton9513]

This is a very informative video, highlighting many issues that are often overlooked by almost every diver who occasionally dives Nitrox.

[@craigmiles298]

Fantastic video. Been diving on nitrox for two years and I've realy learned a load from this video. Many thanks and keep up the great work.

[@UKDiver]

Here’s for the positive vibes pal! I really do appreciate it. Glad you likes the video. Be sure to check out the website to for more hints and tips 😎

[@cwilliams6884]

it should be noted that an air conditioner will remove moisture from the air so the humidity in a building with air conditioning will be much lower than the humidity outside

[@turgutvelettin6727]

Thanks Andy for sharing that was very educational 👏👏👏👏🤙🤙🤙🤙

[@UKDiver]

No probs man. Glad you found it useful

[@stevenbaxter5149]

Brilliantly educational video mate, I consider myself relatively informed on diving but this information didn't enter my thought process! I shall be ANALysing my gas mixes a lot more accurately now thanks to your good self 👌 cheers mate

[@UKDiver]

Cheers Steve, I’m glad you found it useful! We’ll have to catch up on a dive soon 👍

[@stevenbaxter5149]

@@UKDiver yeah that would be fantastic mate, maybe we should try and get our 2 clubs together for a weekend of east coast diving 👌

[@UKDiver]

@@stevenbaxter5149 great idea. I know as soon as we can we’ll be out on the east coast. Drop me an email pal with more details about you and your club and we’ll get something sorted 😎😎

[@stevenbaxter5149]

@@UKDiver whats your email mate and we can try and possibly sort something out 👌

[@UKDiver]

@@stevenbaxter5149 [e-mail]

[@albertokusmic9239]

Very well explained, thanks for sharing! 👌

[@UKDiver]

No worries. Dive safe 👍

[@Yggdrasil42]

Thanks, you mention the display lock is hendy while blending your own Nitrox. Could you please explain how you'd use that feature?

[@UKDiver]

The way I use it is once the reading has stabilised, I lock the screen and then I don’t have to worry about the reading changing whilst I’m completing the paperwork or showing the client the mix if I’m blending for anyone else. I don’t use it if I’m just doing a check on my own gas, but deffo a useful feature especially if you’re mixing your own 👍👌 Dive safe!

[@Yggdrasil42]

@@UKDiver Ah I see. Thanks, that makes sense.

[@jondouglass-bull6729]

Excellent explanation

[@UKDiver]

Cheers Jon. Appreciate the comment 👍

[@matthewwilliams2128]

Hang on - you can't use the Google outdoor humidity and your living room indoor temperature. Got to be temp and humidity of the same parcel of air jj

[@UKDiver]

That’s correct. It’s pretty clear I wasn’t filling that cylinder while I was making the video as I don’t have a compressor in my living room 😂. If you decide to calibrate by finding out the current humidity level then obviously you have to do it there and then whilst your filling. However, the best and most reliable way to calibrate is to use a known air cylinder as I say in the video. It’s dry air and therefore no need to worry about humidity at all 👍

[@jean-pierreross1027]

have a nice dive from montreal

[@UKDiver]

Cheers!

[@darrenbrewer7587]

Hi Andy, thanks for the vid. Would be interested in the reading of the nitrox mix when the ANALox is set up from the chart for relative humidity then crossed ref to when calibrated to a tank of known qty. We would expect the same but is this the case. Very interesting the effect of pressure on the sensor reading I'm sure many divers do this wrong, I have been thinking of buying my own tester for a while now to take on trips that haven't happened due to covid I take it you would recommend ANALox? Sorry can't help myself with the capital letters 😁

[@UKDiver]

Ahhhh Darren, a teenager trapped in an adult body just like me! 😂 With regards to your first question, the only way to ensure the mix percentage was known would be to use 💯 O2 as any other mix will ALWAYS be variable due to the type of testing unit, the accuracy of the unit and all the other variables. Remember also that the Ananlox is only accurate in itself to +/- 0.5% so there will always be slight variation. I’m just trying to show you how to not introduce even more in by incorrectly calibrating the unit in the first place. That aside, I can’t see any reason why we couldn’t do a test with 💯 O2 as and when I can get access to some 👍 Yes I would recommend this unit. Well made, simple to use and reliable. Come up regularly second hand, often needing a new sensor. These can be bought from Vandergraph in Leeds for around £40 when in stock as currently all cells are being snapped up for use in respirators for treating COVID patients. A more worthy cause I’m sure you’ll agree 👍 but as and when things return to normal, yeah, keep an eye out as they are handy, if not necessary, to have. Dive safe pal 👍😎 Andy

[@tridoc99]

Great video! It may be too hard to explain here, but I don’t understand how the O2 percent can increase as the cylinder cools. The fraction of O2 molecules to N2 molecules can’t change in the closed system. Does it have to do with changes in partial pressure due to differences in the weights of the O2 molecule vs the N2 molecule so the changes to their partial pressure with temperature are not linear? If you have a link to a resource I could read up on and learn the answer that would be awesome!

[@UKDiver]

Hey. I’m afraid the only resource I could provide is the BSAC course manuals. But you’d have to do the course to get hold of those. The non - linear weirdness gets worse the higher the pressures get and it’s weirder still when your blending tri-mix. Excellent courses I recommend them all 👍

[@generalmustache9762]

Just one question why don't you callibrate it agains 100% oxygen?

[@UKDiver]

Hey. Well a few reasons. Firstly, as the O2 sensor reacts with oxygen, blasting it with neat O2 will fry the sensor much quicker than not. Second, you have to be qualified to use 100% O2 as it doesn’t play well with oils and such and not everyone who is qualified to use Nitrox will be qualified to use 100% O2 and you really don’t want and oxygen fire on your hands. Thirdly, if your testing anywhere else other than the fill station, perhaps if you’re whipping gas across to top up a cylinder and are testing the residual mix, you may not have access to 100% and finally there is the cost, bit of a waste of gas to calibrate an analyser that can just as easily be calibrated with known dry compressed air. Hope this answers your question! Thanks for watching 👍👍

[@greatwhitesharky3261]

Hi, Should you start with the analyser on 20.9 or 21? ta

[@Yggdrasil42]

You should calibrate using the percentage from the table he shows in the video. If you don't have it available you can use 20.9, which is the 'standard' percentage om normal air. It may be a bit off depending on temperature and humidity so stay conservative in your diving.

[@greatwhitesharky3261]

@@Yggdrasil42 exactly, so many divers out there don't understand temperature/humidity can effect the readings.