Would you really know what was going on if your computer went into Deco...?

[MikeFerrara]

Does any one have their DAN card handy. This might be a good time to post the emergency number.

 

[rcohn]

Let's remember the original question was

Would you really know what was going on if your computer went into Deco...?

This is clearly a recreational diver's question, not a technical diver intending to enter into planned decompression dives. Unforeseen circumstances such as an entanglement could send a diver into decompression range. They will also be stressed and might misinterpret an unfamiliar display on their computer.

Keeping that in mind let’s consider your comments.

Just a start...
A more reasonable way to do it is to learn to make ascents and descents with presice control while managing other taske or problems at the same time. Can you precisely control depth and maintain buddy contact and replace a mask?

Isn’t precise control what every diver practices during safety stops? After all many like to say “every dive is a decompression dive”. Remember the original question is would you understand your computer’s display if it went into decompression mode.

Just a start...
Learn the planning and responses to problems like a lost decompression gas or malfunctioning reg on a decompression gas and responding to problems like ommited stops (as in say you took an injured diver up).

Recreational diver do not carry decompression gases, therefore we do not need to know what to do if the gas we never carry or use is lost. The dive computers have omitted decompression built into the algorithms (typically return to stop within 3 to 5 minutes). Beyond that, most authorities would advise a recreational and probably a technical diver to get out of the water, breathe O2, and monitor for symptoms of DCS. Obviously learning an omitted deco procedure is a good idea for all divers.

Just a start...
Now that you can execute a schedule all you need to know is how to figure out what it should be.

Again, this was a recreational computer diving question based on accidentally going into deco mode due to inattention or mishap. The computer will guide the diver through the necessary stops. The profile can be improved by adding additional deep stops if that is the diver’s usual practice. This is an area where it is valuable to test the computer in deco mode to understand how additional deeper stop(s) would affect the computer's planned profile.

Ralph

 

[truva]

The original question was what would you do if you went over and your dive became a “deco” dive according to your computer. Now we’re calling DAN? The Suunto computers will cover you in this situation; they say not to use it for “deco” dives for the same reason no one else wants to take responsibility for the actions of others.

Why are there people here that think their way is the only way? Sometimes this place sounds like a Baptist Convention in its intolerance. This isn’t the Tech forum or DIR, this is the Basic SCUBA forum.

Exceeding the NDL limits by a few minutes because you just want to and you have the gas to complete your obligation is an easily manageable risk. I don’t call DAN when I do it and I for sure don’t let a Joe Dive Master check my computer afterward.

Truva

 

[kalvyn]

Does any one have their DAN card handy. This might be a good time to post the emergency number.

Diving Emergencies (Remember: Call local EMS first, then DAN!)
1-919-684-8111
1-800-446-2671 (toll-free)
+1-919-684-9111 (Latin America Hotline)



For what it's worth, I've put my Mosquito into deco twice, both on fairly deep (for recreational!) dives (124 fsw). By the time I actually got up to 20 fsw, the deco obligation (5 minutes at or below 10 fsw) was long gone.

The key, as has already been pointed out, is to understand that the computer is not telling you to go to 10 fsw IMMEDIATELY and sit for 5 minutes, then get out. Unfortunately, if the person wearing said computer doesn't understand this and DOES shoot up to 10 fsw and wait the 5 minutes out, poop could occur. This is where I agree that diving a computer could actually do more harm than good... but it's the human causing the problem, NOT the computer.

Jimmie

 

[MikeFerrara]

The original question was what would you do if you went over and your dive became a “deco” dive according to your computer. Now we’re calling DAN? The Suunto computers will cover you in this situation; they say not to use it for “deco” dives for the same reason no one else wants to take responsibility for the actions of others.

Why are there people here that think their way is the only way? Sometimes this place sounds like a Baptist Convention in its intolerance. This isn’t the Tech forum or DIR, this is the Basic SCUBA forum.

Exceeding the NDL limits by a few minutes because you just want to and you have the gas to complete your obligation is an easily manageable risk. I don’t call DAN when I do it and I for sure don’t let a Joe Dive Master check my computer afterward.

Truva

No this isn't the tech forum but when people start talking about running their recreational computer into decompression just to see how it works I get worried and get the urge to post the DAN phone number in my sig line just to make sure you all have it. I don't think any one actually called. Did they?


BTW, when you do it do you have enough gas left for your buddy to make that ascent with you if he doesn't?

 

[MikeFerrara]

Let's remember the original question was This is clearly a recreational diver's question, not a technical diver intending to enter into planned decompression dives.

I'm sorry but didn't Dandy Don suggest putting the compyter into decompression on purpose?

Isn’t precise control what every diver practices during safety stops? After all many like to say “every dive is a decompression dive”. Remember the original question is would you understand your computer’s display if it went into decompression mode.

Well I would hope this is every divers goal but many just clump up on the line during safety stops. That isn't good enough when you have a decompression obligation because there isn't always a line. I wasn't speaking to the original question. I was speaking to Don's suggestion for a way to practice. I gave what I thought was better preperation. Read the book or use the simulation mode to understand the display.

Recreational diver do not carry decompression gases, therefore we do not need to know what to do if the gas we never carry or use is lost. The dive computers have omitted decompression built into the algorithms (typically return to stop within 3 to 5 minutes). Beyond that, most authorities would advise a recreational and probably a technical diver to get out of the water, breathe O2, and monitor for symptoms of DCS. Obviously learning an omitted deco procedure is a good idea for all divers.

I was listing things that should be learned before going into decompression on purpose.

Again, this was a recreational computer diving question based on accidentally going into deco mode due to inattention or mishap. The computer will guide the diver through the necessary stops. The profile can be improved by adding additional deep stops if that is the diver’s usual practice. This is an area where it is valuable to test the computer in deco mode to understand how additional deeper stop(s) would affect the computer's planned profile.

Ralph

I don't beleive that I'm reading this. The way to test the computer decompression mode is by using it's simulation mode not by going out and doing a staged decompression dive. In most recreational computers this is an emergency management feature only. You're talking about creating the emergency on purpose to see how it works.

You're kidding right?

 

[Rick Inman]

Sometimes this place sounds like a Baptist Convention in its intolerance. Truva

Hey, now... Some of my best friends are Baptist, and they tolerate me.

 

[Spectre]

My computer displays my MOD for the gas mix I'm using. Does that mean I need to drop down to that depth and spend my whole dive at the floor? Obviously not. So why do people insist on assuming that a ceiling implies to _go_ there. It's telling you what not to exceed; and how long to make your ascent. It says nothing about going to that ceiling and waiting it out.

There was a thread a while back where a computer was blamed for being screwy, when it was all diver error and mis-use of the computer... it might be worth a read:

http://www.scubaboard.com/t27465.html

 

[IndigoBlue]

...For what it's worth, I've put my Mosquito into deco twice, both on fairly deep (for recreational!) dives (124 fsw). By the time I actually got up to 20 fsw, the deco obligation (5 minutes at or below 10 fsw) was long gone.
...

I wish the scuba agencies would not teach that arbitrary 130 ft recreational limit. NACD publishes 100 ft, more specifically intended for cavern diving. However I have found 100 ft to be a much more reasonable max depth for non-tech diving. And for new divers who have not taken AOW yet, I tell them 50 ft should be their max depth limit.

For a 100 ft NDL dive, a deep stop at 50 ft for 1 min is warranted, followed by a second safety stop at 15 to 20 ft for 3 to 5 minutes. That is what your Suunto Mosquito is probably trying to tell you.

But in the first place, a dive over 100 ft is probably an unsafe dive, particularly if on air (21%O2, 78%N2, etc). Nitrox is a better mix for diving in the 50 to 100 ft range, because Nitrox lowers your EAD and is more efficient for offgassing during ascent and on your safety stop(s).

NAUI, YMCA, SSI, & PADI NDLs exist for your safety, and they are already jacked down about 10% from USN/NOAA NDLs. Even so, the message should have come across in basic open water training that NDLs should not be pushed to their limits.

What does this say for going into deco? Clearly, it means you should not even get close to deco, for recreational diving.

 

[MikeFerrara]

My computer displays my MOD for the gas mix I'm using. Does that mean I need to drop down to that depth and spend my whole dive at the floor? Obviously not. So why do people insist on assuming that a ceiling implies to _go_ there. It's telling you what not to exceed; and how long to make your ascent. It says nothing about going to that ceiling and waiting it out.

There was a thread a while back where a computer was blamed for being screwy, when it was all diver error and mis-use of the computer... it might be worth a read:

http://www.scubaboard.com/t27465.html

Well given the logic of this thread... "NDL's are something that the computer displays so that it can be avoided and every one here thinks that you need to go there to see how it works...it sounds to me like you need to go below your MOD to test the computers reaction.

I would recommend against it but some one would accuse me of trying to force them to do things my way. You could test your buddies ability to handle a toxing diver at the same time.