What if...? Computer Issues

[Dive Hawk]

***Computer Issues***

*What would you do if your computer stopped working during a dive?

If my computer stopped working during a dive, I’d inform my buddy and/or divemaster that I was thumbing the dive. I’d then make a normal ascent using my watch (watch includes a depth gauge) making a three minute safety stop at 15 feet.

* What would you do if you exceeded your NDLs (table or computer)?

I would follow the protocols written into the computer. If using a table, I’d follow the plan we’d set before the dive.

* What would you do if your buddies computer went into deco but yours still showed NDL time remaining?

We’d follow his computer, as you always follow the more conservative computer aka the Suunto!

* What would you do if you were gearing up on the boat and realized you forgot your computer and no one had an extra?

First, you would never use another person’s computer as your own. If you have a depth gauge and an air pressure gauge, and you understand how to plan a dive using tables or an eRDP, you should be good to go.

 

[g1138]

Bad internet connection last night, apparently everything didn't get posted.

All good answers from the new divers, but there's one thing some are forgetting to mention.
- What if you were low on air
-How to you deal with your buddy? For this example take control, you tell us the reader what you would tell your buddy to do; you're the diver in command.
- What do you do after the dive is over?

Try to think of these situations specifically. It doesn't always end after you finish the dive.
Here's my take on the situation. This isn't universal, but rather advice. Take it as it is and apply your own logic and reasoning to it

* What would you do if your computer stopped working during a dive?

I'd let my buddy know and begin a safe ascent ASAP, along side my buddy. If my buddy had good buoyancy control I'd trust him/her to be my point of reference for a safety stop. After surfacing I'd wait 24 hrs before diving again on tables or a computer.

* What would you do if you exceeded your NDLs (table or computer)?

Let my buddy know and end our dive. I'd skip the optional Deep stop and would instead go for my deco stop as dictated by my computer. I assume this is at 15-20ft as it states on NAUI tables. I'd hold the deco stop until my computer clears me or until my buddy and I are down to 300psi (personal preference). I would share air with my buddy or vice versa if needed to complete our deco stop.
Once cleared or low on air we would then surface.
I would not leave my buddy he/she still had a deco and I had cleared. I would expect the same but wouldn't force my buddy to stay down with me. If my buddy decided to surface and I still had the air, I would try to complete my deco stop.
If I didn't clear the deco stop I would ask for O2 and not dive until my computers clears me to. I would also ask to be monitored for signs of DCS

* What would you do if your buddies computer went into deco but yours still showed NDL time remaining?

The same procedure as above, but swtiched roles. I will always follow the most conservative computer within the buddy group if one computer in the group has an obligation (ie. deco stop). If you don't know which computer is more conservative here's a hint: it's the one that goes into deco sooner.

* What would you do if you were gearing up on the boat and realized you forgot your computer and no one had an extra?

First off my computer is attached to my first stage. No computer, no first stage, no diving. Even is I had my first stage and no computer, I would have to skip out on diving. I carry no analogs beside my pressure gauge.
If I have no timer, depth gauge, and pressure gauge, I'm not going diving.

 

[Cave Diver]

Ok, time to throw another wrench into the scenario.

You've recently finished your AOW class and for the first dive of the day you're doing a shore dive and exploring the outside of a wreck sitting on a hard bottom. It's a multi-level dive where you and your buddy went to the sand and worked your way up around the wreck as you explored it. You've been keeping a close eye on your computer and consistently checking it every 5 minutes. Neither of you has a backup computer, but you both have tables back on shore with your log books. You are using a wrist mounted computer. Your buddy is using an air integrated computer and he is also wearing a watch that records depth, time and temperature. You are just wearing a standard dive watch. The last time you looked at your computer you had 7 minutes of NDL time left. When you look next, your computer is blank and doesn't respond. You glance at your buddies watch and see the following information:

Spoiler

Question 1: Describe your next courses of action, until you're safely back on shore. Please be as detailed as possible in your response.

Question 2: Based on the information and the circumstances given, can you still make a second dive on the wreck? If no, why not? If yes, explain your dive plan.

Question 3: Explain what difference, if any, your response to question 2 would be if your buddies dive computer failed instead of yours.

 

[Jewls]

Question 1: Describe your next courses of action, until you're safely back on shore. Please be as detailed as possible in your response.

Thumb the dive immediately and make a slow ascent at 30 ft per minute, while buddy watches time and depth at the safety stop, inflate SMB, surface and inflate BCD. I would assume from this point I would have to surface swim to shore. Prior to the shore dive, my buddy and I should have chosen an offshore object as a reference point in which to exit and have a compass to guide us safely back to shore. I can either surface swim with snorkel or regulator. I could also switch between snorkel and reg until I reached the shore, while carefully monitoring air supply on my SPG.
(I have no idea if this is the right way to proceed, I’m interested to see what the more experienced divers have to say about what procedure to take.)

Question 2: Based on the information and the circumstances given, can you still make a second dive on the wreck? If no, why not? If yes, explain your dive plan.

Today, I cannot make a second dive to the wreck for several reasons.
1. My computer has failed and the rule is that you should not dive for at least 24 hours.
2. The dive tables (assuming I do not have the eRDPml) does not account for multi-level dives, only a single depth.
3. I should not share a dive computer. Therefore, I cannot use my buddies profile to calculate my next dive, even if I did have an eRDPml.

Question 3: Explain what difference, if any, your response to question 2 would be if your buddies dive computer failed instead of yours.

I would suggest to my buddy to follow the same procedures as given in answer #2. Not to dive for at least 24 hours.

 

[Jax]

Computer Issues
* What would you do if your computer stopped working during a dive?

Look at the one on my right wrist; if that goes, I'll pull the one out of my pocket. BTW, I also have SPG(s) and watch.

* What would you do if you exceeded your NDLs (table or computer)?

Since I've trained for it . . . I'd kick my own butt for it!

* What would you do if your buddies computer went into deco but yours still showed NDL time remaining?

LMOA while we waited through his deco.

* What would you do if you were gearing up on the boat and realized you forgot your computer and no one had an extra?

Out of six computers? I'd shoot myself!

 

[Charlie99]

....It's a multi-level dive where you and your buddy went to the sand and worked your way up around the wreck as you explored it. You've been keeping a close eye on your computer and consistently checking it every 5 minutes. .... You are using a wrist mounted computer. Your buddy is using an air integrated computer and he is also wearing a watch that records depth, time and temperature. You are just wearing a standard dive watch. The last time you looked at your computer you had 7 minutes of NDL time left. When you look next, your computer is blank and doesn't respond. You glance at your buddies watch and see the following information:

(pic of dive watch showing 82' max, 76' present, 28:32 elapsed dive time.)

Unless you have gone shallower and then descended back down, that's an awfully low profile wreck and the dive wasn't very multilevel.

82' max, 76' present sounds pretty much like around 80' average depth. That also matches that my Oceanic computer would say is approaching NDL.

Question 1: Describe your next courses of action, until you're safely back on shore. Please be as detailed as possible in your response.

I would both turn the dive and simultaneously start our ascent. At the first stop, I'd ask to see his air integrated computer out of curiosity. I would NOT ask to see his computer before starting the return and the ascent, since that just extends our bottom time and I already know that we are approaching NDL.

Just to make things interesting, let's assume that his AI computer had failed also.

I started my ascent assuming that I am right at NDL and pushing the limits. For that condition I decide on 7 minutes for ascent, so I will surface at runtime 36 at the earliest. 30fpm up to 50' and slow. Leave 40' at 31 (ascent start + 2) minute runtime. Leave 25' at 32 minute runtime (ascent start +3), headed for 20'. Do 1 minute there, then start sliding up to 10' over the next 2 or 3 minutes. Continue swimming to shore during all of the ascent, stopping if we get to 15' depth or so. If I want to pad my safety a bit more, when I get to 10 or 15' depth, I'll hang out for a couple more minutes. The above assumes that we are on track with air pressures as agreed before the dive.

Question 2: Based on the information and the circumstances given, can you still make a second dive on the wreck? If no, why not? If yes, explain your dive plan.

Yes. I'll treat the dive as a square profile 80', 30 minute dive. After an hour or so of SI, I'll be good for only 16 minute at 80', so it would hardly be worth it to head out to the wreck again. Maybe I'll wait 90 minute SI, after which I could do 20 minutes at 80', but more likely I'd find a shallower reef for my second dive.

I am well aware that technically, since the max depth was 82' that I should be using 90' on the table, but in real life a few minutes excursion to 82' at the beginning of the dive is more than balanced out by the same amount of time afterwards at 75'.

I use my buddy's computer as a sanity check on my calculation.

I'll liberally pad my ascent and stops to take care of any ambiguity of the profile we just did.

Question 3: Explain what difference, if any, your response to question 2 would be if your buddies dive computer failed instead of yours.

Since his is AI, he has lost air pressure info. He needs to fix it before diving or replace it with standard SPG. It also presents a potential problem during the return to shore after computer failure, since we are simply relying upon the fact that, at any point in the the dive, that each of us has enough air to get both of us back to safety while sharing air.

 

[Cave Diver]

Look at the one on my right wrist; if that goes, I'll pull the one out of my pocket.

Out of six computers? I'd shoot myself!

Assume this is normal recreational divers who are fairly new and only have one computer each, not 3.

 

[Cave Diver]

Unless you have gone shallower and then descended back down, that's an awfully low profile wreck and the dive wasn't very multilevel.

82' max, 76' present sounds pretty much like around 80' average depth.

A very good and well thought out response. The average depth approach is the one I would probably use, but slightly different than the one I had in mind. Many newer divers have likely not been exposed to the concept of depth averaging or it's use in calculating NDL times. There is a second approach that might yield different results.

In the scenario I originally presented to someone the profile information was slightly different. But I had a specific reason for incorporating that picture so I decided to just go with the information that was on it. (there are two clues in it that may affect the details of your answer slightly as well)

 

[gcbryan]

It's not much of a multi-level dive if the max depth is 82 feet and you have been continually moving upslope (per your description) and you are only at 75 feet currently. If your computer last showed 7 minutes before NDL and you check every 5 minutes and you have been moving upslope then you are still fine. Ascend. I'd take my time from 30 fsw to the surface but that's just a precaution.

Yes you can do another dive. Just treat this dive as a dive of 30 minutes at 90 feet (conservative) or 80 feet...whatever. Plan the second dive using your tables.

If you buddies computer fails there is no second dive since his is air integrated and I'm assuming that he has no SPG. If your computer fails you can do a second dive as detailed above if you borrow his dive watch which unlike yours includes depth info. Just plan the second dive as a square profile using your dive tables.

I know this was initially for new divers but Charlie isn't a new diver and since some time has passed I thought I'd give it a shot

 

[Cave Diver]

If your computer fails you can do a second dive as detailed above if you borrow his dive watch which unlike yours includes depth info.

Another piece of the puzzle falls into place.

My original scenario had a dive to 82' for 37 minutes, but I wanted to include the option of using a watch as a depth gauge, so I wanted to mention the Aqualand for those that weren't familiar with it. When I found that pic and saw how close the display was to my parameters, I couldnt resist including it.