You definitely will have residual nitrogen after the safety stop. The smallest bubbles go too fast, use your depth gauge and bottom timer to go 10m per 1 min.
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Remember that whole flying after diving rule? And calculating your RNT and pressure groups between dives? No, the 3 minute safety, not deco, stop does NOT completely purge the system...Thanks for the input guys. I'm presuming, too, that the 3min @ 5m/16ft deco stop does completely purge the system of residual nitrogen so even if using the 'smallest bubble' advasc method you are still safe?
Remember that whole flying after diving rule? And calculating your RNT and pressure groups between dives? No, the 3 minute safety, not deco, stop does NOT completely purge the system...
There is no contradiction here.
The PADI RDP was based upon the standard ascent rate when it was created--60 FPM. All their research was based on that ascent rate, and the table they created was based on that ascent rate. That means they cannot change that recommendation when you are using the tables, because the numbers on those tables would no longer be valid.
That is not what the computer version of their course says, though. There they tell divers to ascend at the rate called for by the computer algorithm they are using, which as Diver0001 says, is almost certainly going to be 30 FPM.
Your ascent rate depends upon the system you are using to control your dives.
Thanks for the input guys. I'm presuming, too, that the 3min @ 5m/16ft deco stop does completely purge the system of residual nitrogen so even if using the 'smallest bubble' ascent method you are still safe?
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You have a great timing device. It is a classic! It will actually show you seconds, which most dive computers will not do (they only display minutes). Keeping an eye on your depth gauge, and your dive watch, you should be able to manage your ascents, to keep the rate in the 30 - 60 fpm range. As many have suggested, keeping the ascent rate closer to 30 rather than 60 is the prevalent practice these days. But, if you ascend at 45 fpm rather than 30, it is NBD. I wouldn't worry about tracking bubbles, or trying to distinguish between small bubbles and large bubbles. Ascend 15 feet, letting 30 seconds elapse. Ascend another 15 feet, and let another 30 seconds elapse. There are no data to suggest that you cannot dive safely with that approach. Just because a device gives a digital readout does not necessarily mean it will make you safer. I didn't have a DC for the first 3 years and several hundred dives I did. I just watched my depth gauge and inexpensive digital watch from Chez Target (which was nowhere near as nice as your Citizen ). Even today, while I usually dive with 2 (not inexpensive) DCs, I have a pretty good visceral sense of how fast I am ascending (developed by watching my time and depth, NOT some readout on my DC), and do most ascents with 15 foot increments, and don't assiduously watch my DC-monitored ascent rate.. . . my information equipment is only a Citizen Promaster Diver AY5000-05L, instrument console depth gauge and a PADI eRDP. Any thoughts, opinions, recommendations, etc, about this would be appreciated.
Excellent advice!PfcAJ:Learn to use a watch and your depth gauge.
Practice and master your equipment. Strong basic skills are valuable.
You have a great timing device. It is a classic! It will actually show you seconds, which most dive computers will not do (they only display minutes). Keeping an eye on your depth gauge, and your dive watch, you should be able to manage your ascents, to keep the rate in the 30 - 60 fpm range. As many have suggested, keeping the ascent rate closer to 30 rather than 60 is the prevalent practice these days. But, if you ascend at 45 fpm rather than 30, it is NBD. I wouldn't worry about tracking bubbles, or trying to distinguish between small bubbles and large bubbles. Ascend 15 feet, letting 30 seconds elapse. Ascend another 15 feet, and let another 30 seconds elapse. There are no data to suggest that you cannot dive safely with that approach. Just because a device gives a digital readout does not necessarily mean it will make you safer. I didn't have a DC for the first 3 years and several hundred dives I did. I just watched my depth gauge and inexpensive digital watch from Chez Target (which was nowhere near as nice as your Citizen ). Even today, while I usually dive with 2 (not inexpensive) DCs, I have a pretty good visceral sense of how fast I am ascending (developed by watching my time and depth, NOT some readout on my DC), and do most ascents with 15 foot increments, and don't assiduously watch my DC-monitored ascent rate.
Yes, even as just an 'occasional diver', you can dive safely with basic equipment, and you will fare better with good skills than by reliance on technology-managed ascents.Excellent advice!
My Perdix does as well. And, it took me a while to realize what the advancing bar meant. (Of course, when I actually went back and read the manual, it was an 'Aha!' moment. ) I prefer my (sadly, no longer made) Liquivision X1, which does show seconds. And, I like the 'seconds' feature for deco stops.My Petrels actually have a seconds bar under TIME. You can't read it to the second, but you can definitely read it to see how far along in the computer's minute you are before it clicks over to the next minute. The seconds bar gradually underlines TIME until it goes blank and starts over. It took me forever to notice this. I usually read my computers in glances!
Thanks for the input guys. I'm presuming, too, that the 3min @ 5m/16ft deco stop does completely purge the system of residual nitrogen so even if using the 'smallest bubble' ascent method you are still safe?