What to do when you no longer trust your computer ....

[Doc Intrepid]

..."The fact that my dive buddy / spouse also uses the same two models of dive computer as I do while diving with me increases the team level redundancy"...

Do you mean you and your buddy routinely do every dive with four computers?

 

[Diver Dennis]

I would never use someone else's computer even if they are in my team.

 

[bradshsi]

The TUSA IQ-700 and the Dive Rite Nitek3 both use a Buhlmann algorithm. The primary difference is the TUSA algorithm uses 12 theoretical tissue compartments while the DR NT3 uses 9 theoretical tissue compartments. The half-times of the fastest and slowest theoretical compartment are the same for both models, the TUSA has 3 more between slowest & fastest than the DR NT3.

Having used both side by side on recreational dive profiles, the TUSA is slightly more conservative - not my much. Say I've done a two tank day dive and a night dive within the last 24 hours. The TUSA might show 22 hours and 30 minutes to completely desaturate per the algorithm, the DR NT 3 might say 22 hours and 15 minutes for the same parameter. In terms of NDL time remaining, I've never seen them differ by more than 2 minutes on any profile I've executed while wearing both.

You've obviously done a fair amount of comparison with your 2 computers. As you say having the same algorithm helps. Even so given that both the algorithm and how it is programed have an effect, you can't be certain that the performance of both computers will be consistant 100% of the time. At best you can only be "very sure".

Though personally if I was to use computer(s) (which I don't for previously stated reasons), I'd find your approach logical for risk mitigation.

The fact that my dive buddy / spouse also uses the same two models of dive computer as I do while diving with me increases the team level redundancy.

I'd have to disagree with that statement. You rely on your own computer(s). You can't be sure your buddy is on the same profile as you are. If both your computers fail you call the dive.

Thanks for the informative post. I've enjoyed reading the different viewpoints on this thread.

 

[Zero]

Compact two gauge console (depth & pressure) clipped on left chest D ring.

Vyper and Timex Reef Gear watch on right wrist.

Suunto SK7 Compass and Sunnto D3 (Depth & Bottom Timer) on left wrist.

Dive tables in right pocket of X-shorts.

and yes my buddy has a similar configuration. Hopefully, we have all the bases covered in case of a failure.

 

[moneysavr]

Dive the tables dive the tables!

 

[ghostdiver1957]

Buy A New Computer

 

[WarmWaterDiver]

Do you mean you and your buddy routinely do every dive with four computers?

Yes.

 

[gcbryan]

Do you mean you and your buddy routinely do every dive with four computers?

I'll bet they have four regulators too.

 

[jeckyll]

Dive the tables dive the tables!

Well that would make alot of sense ... unless you take into account that all my dives so far have been shore dives. Even the wheel wouldn't work out all that well given the diving around here (many many levels ).

Darnold: As for the 'using your head' part of the dive planning, maybe we dive different here in Canada (note: for those of you that are need it pointed out, that is a JOKE ).

 

[pt40fathoms]

I have an analog depth gauge and a Timex Ironman watch as my backups. I dive tables exclusively when doing deco dives, and as a result, I can switch to NDL tables quickly in the event of a computer failure when not doing a planned deco dive.

I have not had a failure with my dive computer....yet, and have a few hundred dives on my current model. But like all things that run on batteries and witchcraft, they can do the unexpected, just when you least expect it.

>>Advice Mode ON<<

Carry two computers, one really nice and spiffy with all the blinking things and stuff, and one that just gets the job done for a backup. Or make sure you have an analog depth gauge and timer along for ALL your dives, and put that plastic dive table in your BCD pocket where it belongs! Not in the bottom of your dive bag all lonely and forgotten.

>>Advice Mode OFF<<

Now lets see who listens to advice, and starts carrying some backup?