How to safely ascend with Spare Air

[ShakaZulu]

Someone explain DCS to Fisherdvm...........he's on a dangerous path here. DCS is what kill divers.

 

[wedivebc]

Thank you for the comments.

First, as far as diving is concerned, I am stupid. I have not dove for 10 years.

Second, I should not be trusted under the water, I have doved only 13 times.

Third, all doctors are arrogant, so I am not an exception.

Fourth, I am the stupid kid who keep on asking questions.... That's why I could not stop going back to school....

You guys are having too much fun... so I am joining in too...





But I am learning sooo sooo much....



So as I understand, if you use those stupid tables, and find the category you are supposed to be in, etc. etc... and stay within your time limits.... you should not have accumulated enough nitrogen so you can safely have an emergency ascend without having DCS, is that correct????

The decompression stop at 15 ft and the safe ascent rate of 30/min is a safety measure, just in case you fall outside of the bell curve, or you are too stupid (like me) to use the dive tables. Or too cheap (like me) to buy a dive computer.

So the only issue here is that you don't have to give a hoot about DCS if you obey the tables or the dive computer.

Therefore, your only concern is only with air embolism

Therefore, you must keep on breathing.

Therefore, if sucking on your empty tank is enough to keep your airway open, you will not have an air emboli.

Therefore, if you had a spare air, you would stick it in your mouth, and should have about 1 to 2 min of air - which gives you plenty of time to hit the surface.

Therefore, if you obey all the rules of diving, you really do not need a spare air, a pony tank, etc...

I am really stupid, so please tell me am I wrong????

The use of dive tables are taught in OW class and are easily understood so someone with your vast education will easily pick it up.
The people on this board are not trying to annoy you they are trying to save your life. If you asked a doctors forum 'how much cyanide could I take with out killing myself' you would get a similar response.
Your physiology seems flawed ie. you can close your airway with a reg in your mouth. Your phsics is flawed ie. a tanks holds the same amount of air no matter what depth.
I hope you can also see your diving knowledge needs a little tweaking as well. I am sure I speak for most members here when I say I would hate to hear about someone dying, while trying to do deco on a spare air. It is just insane!

 

[StSomewhere]

I apologize fisherdvm.

I only intended on trying to get you to see it another way. You see, I wanted a Spare Air or pony bottle or ??? too. It wasn't until I had a long discussion on the topic with an instructor and a DM (plus the reading the threads here!) that I began to understand. I only suggested you should take the current OW because it covers exactly what you have questions about. If you are lucky and have a great instructor like I did, you will spend a significant amount of "drill down" time over and above the course's allocated time to really start to understand this. For instance, most embolisms happen within 10m of the surface. Now you wouldn't think that would be the case but like so much in life the important stuff tends to be counterintuitive.

Again, I'm sorry if I came off as pompous or know-it-all (because I don't).

St. Somewhere

 

[Lightning Fish]

Get your pitch forks and torches! There is a Troll in the village!

For someone claiming to be doctor, a vet, and to have previously been certified, be it a while ago, you are showing a great lack of knowledge on topics that you should be knowledgeable about, a lack of understanding, poor reading comprehension skills (I don't see any sign that you are understanding the responses you've been given), and you are not presenting yourself in a mature manner that I would expect from a doctor.

I hope I'm wrong.

Bill.

 

[MSilvia]

Or too cheap (like me) to buy a dive computer.

How is it that someone too cheap to buy a useful piece of gear for a couple hundred bucks can afford to throw money away on a POS like a spare air?

 

[cornfed]

How to safely ascend with a spair air from any depth.
1. deploy it
2. throw it away
3. get buddies primary
4. terminate dive as planed

Don't just throw it away. You can use it to bang on your tank to get your buddies attention since he's probably on the other side of the wreck with his head in a hole searching for bugs.

 

[fisherdvm]

Ouch,...... stick and stone and little nitrogen/air bubbles will hurt me.... but name calling will never.....

Wow, that rescuediver is hot..... she can save me anyday!!!!

You know, I can not find my dive book. It is packed together with about 30 boxes of books I buried in the basement. But it is more fun to discuss stuff on this board.

You are right, the amount of air molecules in an empty tank is still the same. The PSI in the tank is still the same. The only variable is the partial pressure outside of the tank. That is why I am claiming that there are "spare air" in the empty tank.... If you would take a partially empty tank down to 100 ft, empty it out by purging. Take that same tank up to the surface - open up the valve - you should see about 1 cu ft of air escaping. The number of molecules of N, O, and CO2 is the same - but the partial pressure outside the tank is what prevent the tank from fully emptying at 100ft.

If you read the thread.... I saw my errors and admitted that Snowbear was right.... So I proved again that I am stupid.

Yes, I can comprehend the dive tables.....

You are right, I should retake the OW course again....

Thank you for letting me know that most air embolism occurs at the top 10 ft.

Thank you for letting me post on this board, as I am reviewing alot of good information...

Love you all.....

 

[fisherdvm]

Actually I am not a real doctor, I just play one on TV. Don't you understand sarcasm once in a while?

Honestly - no one has answered my question yet:

If you obey the dive table and dive conservatively under the recommended maximum bottom time - can you still get DCS?

If you can't get DCS - then the injury here we are concerned about is air embolism - right...????

 

[fisherdvm]

ShakaZulu, how dare you misrepresent yourself as a gorgeous woman.... I almost lost my heart for you.....

 

[cornfed]

Honestly - no one has answered my question yet:

If you obey the dive table and dive conservatively under the recommended maximum bottom time - can you still get DCS?

Yes.