On your Nitrox video, the 2nd benefit you stated was "shorter surface interval time". After watching this video I was surprised that using air on the first dive yielded a much shorter surface interval time because it seems to fly in the face of the logic from your Nitrox video. Does that make sense?
It does, and what you have to remember though is, you are switching to a richer blend for the second dive, which will help slow the amount of nitrogen that is being absorbed during the second dive, and by helping flush out the residual nitrogen you have absorbed from the first dive. The same principle applies to tech divers during there staged decompression stops. They switch to a richer blend, to help bleed off residual nitrogen they just absorbed through out the dive.
Makes perfect sense now. Thanks for explaining that. Really like your videos. Subscribed last evening. BTW, and to the energy point you made on the other Nitrox video, I am 71 years old and relatively new to SCUBA. (I hope to earn my PADI Master Diver qual next month.) Empirically I notice a huge difference between air and Nitrox in my energy level after a dive. Perhaps I notice it where you don't because of my age. I had 6 dives on air before I began my Nitrox course. I had been really "dragging with energy" after each dive (at 5' 10" and 155# carrying 60# of gear around, maybe 100-200 yards to/from the water). After 2 Nitrox dives in one morning I was sitting on the back gate of my SUV washing my gear when I realized that I still had extra energy. It struck me like a revelation. Since then I have used nothing but Nitrox. FWIW
I think fitness is the key. If you are very fit diver then you dont tend to notice the difference as much. I completed a dive on nitrox and not being that fit noticed a huge difference at the end of the dive in relation to energy levels
My understanding of the PADI air and Nitrox tables are that they can not be interchanged, what ever Nitrox mix you started with didn't allow you to to switch to the air dive table. Does SSI dive tables allow the two to be interchanged?
Hello bikeon143, You can interchange the PADI Nitrox tables and the PADI Air tables, but not PADI and other agency tables. The SSI Air and Nitrox tables are all one table, making it somewhat easier to read. As with any agency's tables, being able to calculate equivalent air depths is crucial, simply because most agencies only show NOAA 1 and 2 (Nitrox 32 and 36), and not other mixtures.
Interestingly, PADI tables indicate no SI for either case. At EAD36 of 50 ft, you exit the first dive at Group M. Require Group R for a 40 ft/60 min air second dive. (Other depths/times do support the Air First conclusion, however.)
Great video! Very informative. I also found that the PADI tables show no SI for either case. I went through all my calculations twice (lol). This was a good review of my Nitrox training info.
Having just completed my nitrox cert for an upcoming trip through padi. I think I really like the ssi tables much better. Way less confusing in my opinion. I would imagine I can just order a set of these?
Hello John Montgomery, you can actually get the digital version for free. First go to divessi.com and create a free profile. Then download the MySSI app from either the play store (on Android) or App Store (on Apple) for free as well. Then use the same log in from the profile you created. The tables are under the tables tab on the app. Hope this helps.
i dont know why someon put thumbs down i thing the video was great informing and etc..i do think nitrox atleast in the higher percentages will make a diver or none diver feel better ...
Do you use the same regulator for Nitrox and Air? Scubapro recommends a regulator be serviced after using it on air before returning it to use with nitrox. I've read that other manufacturers make the same recommendation, but haven't researched it beyond the SP literature.
Hello Alex Millender great question, and yes I do. Most regulators today, if not all of them, are Nitrox ready (at least up to 40%). Also, unless you are diving pure O2 in a Deco cylinder, there is not need to re-clean a regulator after using air.
Bryan no criticism, just trying to understand. Go to the 5 minute mark in the video and you say “go from G to F” for surface interval of 41 minutes but i think you actually went to E for the surface interval of 41 minutes. Is it me?
Hello 391wombat, if you will take a close look at the SSI dive Tables you will notice by intersecting the Pressure Group G with Pressure Group F (on the bottom of the table), that 41 minutes is the minimum surface interval. I believe the confusion is you are looking at the E pressure Group above the 41 minute mark.
LakeHickoryScuba Got it Bryan thanks. I missed the arrows which indicate the column to the LEFT of the designated letter group, not the actual column that the designated letter group is in. John
40 minutes is the maxiumum amount of time you can stay at 70 feet, even if you used the PADI Dive Tables to plan with. Just because it's in the black, doesn't mean you go into DECO. The Black Box is the maximum allowed time, not the DECO time. Though sometimes these two get mixed up.
Thank You and you're welcome. We do however encourage divers to limit themselves from reaching the maximum limits of the dive tables, just to be on the safe side though. For most new divers, reaching their maximum no decompression limit, especially at shallower depths, is limited more by the amount of air they have. Its always better to be more conservative when you dive, more or less, staying away from those black boxes. This extra bit of safety never hurt anyone.
Most computers take up to 24 hours before it will allow to switch back to air mode. If you are making several dives in a day and need to switch back to air, simply leave your computer on nitrox, but set the mix to 21%. after 24 hours, you should be able to switch it back to air mode. I have a Wisdom 2 from Sherwood, and the same applies to it as well.
I've never dived and plan on getting certified for my 21st birthday coming up, so I apologize for my noobie question... so, checking the charts if my first dive was air to 70 ft for 40 minutes im pressure group H, what if my second dive is also air at 40 feet for 80 minutes which is pressure group H, wouldnt that result in a 10 minute surface time and result in an increased second dive time? therefor whats the point of nitrox?
You would need an hour and 42 minute surface interval to make those two dives safely, if you were using air. One of the benefits to using Nitrox is, it allows for shorter surface intervals, thus you wouldn't need to stay out of the water for an hour and 42 minutes between the two dives. When you take your basic open water course, you will learn about minimum surface intervals.
and after watching this video, diver gets all excited and used air for the first dive but forgot to switch the computer to Nitrox. Now the computer is telling him to get the f out of the water lol
I love your videos I have subscribed. I learn so much from your videos.
Thanks Daniel Thompson for the subscribe. We are glad you are liking and learning from our videos.
On your Nitrox video, the 2nd benefit you stated was "shorter surface interval time". After watching this video I was surprised that using air on the first dive yielded a much shorter surface interval time because it seems to fly in the face of the logic from your Nitrox video. Does that make sense?
It does, and what you have to remember though is, you are switching to a richer blend for the second dive, which will help slow the amount of nitrogen that is being absorbed during the second dive, and by helping flush out the residual nitrogen you have absorbed from the first dive. The same principle applies to tech divers during there staged decompression stops. They switch to a richer blend, to help bleed off residual nitrogen they just absorbed through out the dive.
Makes perfect sense now. Thanks for explaining that. Really like your videos. Subscribed last evening.
BTW, and to the energy point you made on the other Nitrox video, I am 71 years old and relatively new to SCUBA. (I hope to earn my PADI Master Diver qual next month.) Empirically I notice a huge difference between air and Nitrox in my energy level after a dive. Perhaps I notice it where you don't because of my age. I had 6 dives on air before I began my Nitrox course. I had been really "dragging with energy" after each dive (at 5' 10" and 155# carrying 60# of gear around, maybe 100-200 yards to/from the water). After 2 Nitrox dives in one morning I was sitting on the back gate of my SUV washing my gear when I realized that I still had extra energy. It struck me like a revelation. Since then I have used nothing but Nitrox. FWIW
You're welcome.
I think fitness is the key. If you are very fit diver then you dont tend to notice the difference as much. I completed a dive on nitrox and not being that fit noticed a huge difference at the end of the dive in relation to energy levels
My understanding of the PADI air and Nitrox tables are that they can not be interchanged, what ever Nitrox mix you started with didn't allow you to to switch to the air dive table. Does SSI dive tables allow the two to be interchanged?
Hello bikeon143, You can interchange the PADI Nitrox tables and the PADI Air tables, but not PADI and other agency tables. The SSI Air and Nitrox tables are all one table, making it somewhat easier to read. As with any agency's tables, being able to calculate equivalent air depths is crucial, simply because most agencies only show NOAA 1 and 2 (Nitrox 32 and 36), and not other mixtures.
Interestingly, PADI tables indicate no SI for either case. At EAD36 of 50 ft, you exit the first dive at Group M. Require Group R for a 40 ft/60 min air second dive. (Other depths/times do support the Air First conclusion, however.)
We hope others study on this as well, just like you did Paul. The more you know, the safer you will be.
Great video! Very informative. I also found that the PADI tables show no SI for either case. I went through all my calculations twice (lol). This was a good review of my Nitrox training info.
Having just completed my nitrox cert for an upcoming trip through padi. I think I really like the ssi tables much better. Way less confusing in my opinion. I would imagine I can just order a set of these?
Hello John Montgomery, you can actually get the digital version for free. First go to divessi.com and create a free profile. Then download the MySSI app from either the play store (on Android) or App Store (on Apple) for free as well. Then use the same log in from the profile you created. The tables are under the tables tab on the app. Hope this helps.
Cool
Glad you liked the video Tony Pasma.
Another excellent teaching video.
Thank You
Is the normal Air has high risk below 50 foot rather than nitrox?
Hello Vanlal Rosangliana, depending on which ppO2 you use, air can become toxic at a depth of 187 feet.
Great info Brian
Thanks Darren Wooten, glad you liked the video.
i dont know why someon put thumbs down i thing the video was great informing and etc..i do think nitrox atleast in the higher percentages will make a diver or none diver feel better ...
Hello BEST GIRL EVER, glad you liked our video and thank you for the kind words.
Do you use the same regulator for Nitrox and Air? Scubapro recommends a regulator be serviced after using it on air before returning it to use with nitrox. I've read that other manufacturers make the same recommendation, but haven't researched it beyond the SP literature.
Hello Alex Millender great question, and yes I do. Most regulators today, if not all of them, are Nitrox ready (at least up to 40%). Also, unless you are diving pure O2 in a Deco cylinder, there is not need to re-clean a regulator after using air.
This was one great instructional video.
Thank You.
Sir i need all tables (padi and nitrox )
Hello @umeshkoushal2788, most agencies have stopped producing their tables. However, the SSI tables can be found on the SSI app. It's a free download.
Hi
Is that a standard SSI dive table to have the 3 common blends?
Hello David, yes, the SSI Tables have Air, 32%, and 36% all on them.
Super!! Well done.
Bryan Shaw Thank You
Bryan no criticism, just trying to understand. Go to the 5 minute mark in the video and you say “go from G to F” for surface interval of 41 minutes but i think you actually went to E for the surface interval of 41 minutes. Is it me?
Hello 391wombat, if you will take a close look at the SSI dive Tables you will notice by intersecting the Pressure Group G with Pressure Group F (on the bottom of the table), that 41 minutes is the minimum surface interval. I believe the confusion is you are looking at the E pressure Group above the 41 minute mark.
LakeHickoryScuba Got it Bryan thanks. I missed the arrows which indicate the column to the LEFT of the designated letter group, not the actual column that the designated letter group is in. John
Great video and very informative
40 minutes is the maxiumum amount of time you can stay at 70 feet, even if you used the PADI Dive Tables to plan with. Just because it's in the black, doesn't mean you go into DECO. The Black Box is the maximum allowed time, not the DECO time. Though sometimes these two get mixed up.
LakeHickoryScuba oh my bad! I thought it meant that thanks for the fast reply and great videos!
Thank You and you're welcome. We do however encourage divers to limit themselves from reaching the maximum limits of the dive tables, just to be on the safe side though. For most new divers, reaching their maximum no decompression limit, especially at shallower depths, is limited more by the amount of air they have. Its always better to be more conservative when you dive, more or less, staying away from those black boxes. This extra bit of safety never hurt anyone.
My dive computer's manual (Wisdom 3) says it won't change to air mode after a nitrox dive. Is this the reason?
Most computers take up to 24 hours before it will allow to switch back to air mode. If you are making several dives in a day and need to switch back to air, simply leave your computer on nitrox, but set the mix to 21%. after 24 hours, you should be able to switch it back to air mode. I have a Wisdom 2 from Sherwood, and the same applies to it as well.
Throw it in the bin, and grab a shearwater perdix.
I've never dived and plan on getting certified for my 21st birthday coming up, so I apologize for my noobie question... so, checking the charts if my first dive was air to 70 ft for 40 minutes im pressure group H, what if my second dive is also air at 40 feet for 80 minutes which is pressure group H, wouldnt that result in a 10 minute surface time and result in an increased second dive time? therefor whats the point of nitrox?
You would need an hour and 42 minute surface interval to make those two dives safely, if you were using air. One of the benefits to using Nitrox is, it allows for shorter surface intervals, thus you wouldn't need to stay out of the water for an hour and 42 minutes between the two dives. When you take your basic open water course, you will learn about minimum surface intervals.
and after watching this video, diver gets all excited and used air for the first dive but forgot to switch the computer to Nitrox. Now the computer is telling him to get the f out of the water lol
Hello Ken10, this is the exact reason we have the Nitrox Course. Thanks for reinforcing that for the viewers.
Dude i like your vids but plz i like them better when you say feat and meter
Hello Tommy, we will make sure to include metric in our physics videos.