How close to your dive buddy...

[TSandM]

Freeflows can empty a tank pretty darned fast, too . . . I happen to know this.

 

[cascas]

Your chances are slim, indeed ... but not "non-existent". The reality is that it does happen ... even at times to experienced divers ... and if you don't have a source of breathing gas handy, then your life is measured in seconds.

Things that can cause even an experienced diver to run out of air ...

- debris clogging a dip tube (ask Dr. Bill about that one)
- an SPG that is either stuck or malfunctioning
- task-loading and/or narcosis

The primary reason to dive with a buddy is to have a redundant air source nearby. If you're going to adopt the philosophy that "it can't happen to me", then I highly recommend a pony bottle ...

... Bob (Grateful Diver)

With my setup (DIR/Hogarthian) :
Debris in a dip tube has to happen twice before becoming a problem.
Malfunctioning SPG is not very likely to cause a big problem if your starting tank pressure and gas consumption is known.
Taskloading and narcosis... these are very easy to recognize and prevent. If those get you in trouble you have crossed your comfort zone border a great deal.

That makes it close enough to non-existent for me....

 

[rhwestfall]

.... thumps chest.... surveys those subordinate....

 

[rhwestfall]

p.s. - is that what/how you teach???????

 

[tr3a]

At the risc of sounding cocky, here goes...

What are the chances that your next breath is the last you get from your tank ? I would say next to nothing.

When diving a diver should have a sense of time and gas consumption. Checking time and spg on a regular basis will eventually lead to being able to predict your tank pressure by just looking at the dive time. If in the first 15 minutes of your dive your tankpressure drops from 200 to 150 bar ( or 3000 - 2250 psi ) it will not be very likely that you will hit 100 bar or 1500 psi within the next 10 minutes if cirumstances do not change drastically.

Checking your spg every 5 - 10 minutes will prevent a situation where your gas supply suddenly stops causing you to start sprinting to your buddy. This will increase your comfort and will enable you to comfortably be more than arms length away from you budy.

A diver that unknowingly empties his tank is a diver that should take up knitting or checkers. Running out of gas is a situation that a no-brainer should be able prevent and should thus be non existent.

Equipment failure will cause freeflow and will deplete your gas supply really quick but gives you enough time to get to your buddy or reach the surface. A failure like this is more likely to happen with higher tank pressures than lower tank pressures so an occurence like this in the second half of your dive is quite low risk.

Knowing your gas consumption and current tankpressure is a much bigger safety measure than staying frantically close to you buddy. Knowing your buddies gas consumption more than doubles that. And if your buddy knows yours, well... need i say more ?

??? Not true

 

[cascas]

p.s. - is that what/how you teach???????

I don't teach (anymore) too busy thumping chest and surveying...

Kidding.. I found recreational courses lacking in so many ways that I prefer not to be a part of that system. Only when someone really is interested ( and not just wanting to go dive on holiday) I will do an OW course. But I add all things I found worthwhile in my Technical and Cave courses. I don't stop at the requirements that PADI wants, I stop when I am satisfied. Even if it takes me twice or three times as much time.
I can cause I'm not in it for the money...

 

[cascas]

??? Not true

Enlighten us then....

 

[MXGratefulDiver]

Cascas ... perhaps before providing answers to the OP's question you should consider the forum you're responding in, and the experience level of the person who asked the question.

I seriously doubt that this person wears doubles, or dives in caves ...

... Bob (Grateful Divr)

 

[tr3a]

Most freeflows I have seen happen well into the dive.

 

[BDSC]

Most of my diving is done in clear tropical waters. I'd say on average I don't want anyone closer to me than 10 to 15ft and no farther than say 40 ft. or so.