Overshooting NDL and mandatory deco stops

[RayfromTX]

Yes you are correct. On the new Teric the defaults are 40/85 for rec and 30/70 for tec mode. I have both my Perdix and my Teric set to 40/85. I apologize for the confusion.

Edited to remove incorrect statement about the default settings on the Perdix.

 

[NAUI Wowie]

Yes you are correct. The default on the perdix is 30/70 for both rec and tec modes. On the new Teric the defaults are 40/85 for rec and 30/70 for tec mode. I have both my Perdix and my Teric set to 40/85. I apologize for the confusion.

40/85 is a less conservative setting? Why is Shearwater going less of a conservative dive profile on the Teric I wonder?

 

[RayfromTX]

The least conservative setting is 100/100 although I don't know if you can actually set 100/100 on the Perdix. That represents the m-value line on the algorithm chart. The further you get from the m-value, the more conservative your dive profile will be. It is the second number that determines your NDL and a setting of 30/70 will give you less bottom time before you incur a decompression obligation than a setting of 40/85 would.

If you ask your question in the Shearwater forum, you may get a response from Shearwater.

 

[tursiops]

Yes you are correct. The default on the perdix is 30/70 for both rec and tec modes. On the new Teric the defaults are 40/85 for rec and 30/70 for tec mode. I have both my Perdix and my Teric set to 40/85. I apologize for the confusion.

No. There is no 30/70 in Rec mode.

 

[NAM001]

Hi Dale.
The reason that you might want to know which GF is appropriate for your diving is because it is possible to change it either on purpose without enough info to make a good choice, or by mistake when scrolling the menus. I dive on the medium setting 40/85 but if I have reason to question my overall health or I'm doing 4+ dives a day I might set it to high conservancy 30/70. It is simply a fudge factor that is applied to the most aggressive version of the dive algorithm that is used by Shearwater. You don't have to study deco science to understand what your settings should be so that you can check and confirm you are diving in a way that you decided for yourself.

Yes, the last 10 feet should be done very slowly like in a full minute. I think the fizzies have a bit to do with sinus passages equalizing on the way up. I could be wrong.

Hi rayform. one thing on your post in rec mode you only have low med and high for selectoins. yo have to go to tech mode to

 

[scubadada]

High conservancy in rec mode is 35/75, default in tec mode is 30/70

Medium in rec mode is 40/85, low is 45/95. Rec mode has just those 3 settings, tec can be custom set

 

[RayfromTX]

Perdix rec mode gf high = 35/75
gf med = 40/85
gf low = 45/95
on tec mode the least conservative value I was able to program was 49/99 or 90/90.

On the Teric the rec mode values are the same but the default is gf medium
Also on the Teric I was able to program in a gf of 99/99 unlike the Perdix.

I will edit my previous post. Sorry

 

[The Chairman]

So you absolutely noticed a difference making the optional safety stop at 15ft 2 minutes longer?

Yes, I did. If there's a crowd waiting to get on the boat, I'll extend my stop as long as they're getting on the ladder and I have gas. If I made a long deco dive in a cave, I relax an additional 5 minutes in waist deep water before I start lugging gear ashore. I would love to sit for five after I get on the boat, but ain't nobody got time for that. Instead, I swap gear and then I sit as long as I am not needed (no students in tow). It's not only important to allow extra time for offgassing at the end of your dive, but you should also be careful that you don't "shake the soda", so to speak. Go slow with the least amount of exertion for the next 15 to 20 minutes and no running or gym for at least 12 hours.

 

[NAUI Wowie]

Yes, I did. If there's a crowd waiting to get on the boat, I'll extend my stop as long as they're getting on the ladder and I have gas. If I made a long deco dive in a cave, I relax an additional 5 minutes in waist deep water before I start lugging gear ashore. I would love to sit for five after I get on the boat, but ain't nobody got time for that. Instead, I swap gear and then I sit as long as I am not needed (no students in tow). It's not only important to allow extra time for offgassing at the end of your dive, but you should also be careful that you don't "shake the soda", so to speak. Go slow with the least amount of exertion for the next 15 to 20 minutes and no running or gym for at least 12 hours.

im going to start doing 5 minute safety stops. But potentially my insta buddies on liveaboards and even monterey random boat weekend dives wont like the extra two minutes on an "optional" safety stop. That could lead to being alone on many safety stops, not worrisome for me though.

 

[The Chairman]

That could lead to being alone on many safety stops, not worrisome for me though.

Let them know before the dive starts and remind them that you should never abandon a buddy in the soup as long as you have gas. Don't be an "SOB", or Same Ocean Buddy: plan to come out together.