Dive comp with freedive capabilities?

[clara.chan]

hi all
I have the shearwater perdix AI. unfortunately, it doesn’t come with a freedive mode. How important is it that I use a computer with freedive mode when freediving? Isn’t time and depth all that’s important, which is something the perdix is fully capable of?
Thanks all!

 

[aquacat8]

Freedive computers do more freedive specific stuff.

 

[aquacat8]

If money is no object you could always back up your Shearwater computer with the new Shearwater watch which actually does have a free diving mode. Otherwise for free diving a nice free diving watch will set you back about $400. Be careful if you’re just getting into Free Diving It’s actually more dangerous than Scuba because of shallow water black out. Read up about it, get a buddy, and never free dive after Scuba.

 

[Nick Steele]

I Started freediving before I started scuba and I never had a watch. Before getting into scuba I never knew how long I was under or how long my surface interval was. I knew I had a dry breath hold of 2-3 minutes so I was never worried because I didn’t stay long and never had the urge to breath I simply came up way before that.

Since becoming certified I have obtained a mares smart computer which has a freedive mode and I use it all the time. It’s nice having the time on the watch for parking responsibilities as well has recording the depth/time of the dive. Since getting the comp I limit myself to 45-60 seconds under since I’m mainly by myself Freediving. Although my deepest recorded is 47’ for 1:40 I don’t do that often and only with a buddy.

 

[RIHappyDiver]

I don’t free dive but kind of remembered something about nitrogen accumulation during free diving, so I looked into it in the manual for my dive computer. Here is what it says regarding it’s free dive mode;

ADDITIONAL INFORMATION PERTAINING TO FREE DIVE MODE
• Although breathing apparatus is not utilized for Free Dive activities, nitrogen tissue loading remains a factor. Nitrogen loading is calculated based upon a xed FO2 of Air.
• Since a user has the option of alternating between SCUBA and Free Dive activities within a 24 hour period, nitrogen calculations and the displayed value of No Deco Dive Time Remaining (NDC time) are carried over from one operating mode to the other, which permits the user to maintain awareness of nitrogen absorption and offgasing status.
• The mathematical models currently used in the GEO 2 are based on no decompression/ decompression multilevel repetitive dive schedules.
• These algorithms do not take into account the physiological changes associated with the high pressures that competitive type Free diving can expose a diver to.

ADDITIONAL WARNINGS
• Ensure that you know which Operating Mode is selected (NORM, GAUG, or FREE) prior to commencing any dive.
• Conducting Free dives within a 24 hour period after conducting SCUBA dives, combined with the effects of multiple rapid Free Dive ascents, increases your risk of decompression sickness. Such activities may result in accelerated entry into decompression which could cause serious injury or death.

Hope that helps,

Erik