Warning deep "bounce" dives warning

[CamG]

Greetings to all divers new, old , or not yet certified.
In recent days there have been some accidents that were a result of dives that have been described as bounce dives.
What are bounce dives?
Well they are dives that are short in duration, Bottom Time but are deep done on single tanks.
What is deep? Well anything that is over 60', past recreational limits, or simply beyond the personal divers training and or gas planning requirements.

At this point some of you will shudder at the mention of gas planning but a single tank does require planning and is taught in OW!
I understand that when you gain more experience your gas consumption goes down but there still is a limit to the available gas.
Whatever gas plan you commit to:
a. return with 500-700psi
b. rule of thirds
c. no plan at all
there are factors that will directly impact your gas consumption.

Conditions; Currents, waves, surface swims,etc.
Personal Physical issues; fitness, hydration,etc.
Personal Mental issues; proper training, anxiety, narcosis,etc.
I am making this very abbreviated forgive me for leaving so many out.

Diving Planning takes your planned dive and these criteria into consideration while tempering it with conservatism to form a safe detailed dive plan that includes emergency procedures for the what ifs.

A BOUNCE DIVE DOES NOT ACCOUNT FOR WHAT IFS!
I am assuming that a true BOUNCE dive is done on a single tank!
I have read of several in the last month and will not mention any particular accident nor wish to demean any diver, agency, LDS that is not my purpose!
My purpose is simple, BOUNCE DIVES ARE NOT SAFE!

If you choose to do this type of dive then be very aware of what DCS is and how it kills those who violate the limits.
It is tragic to loose members of our diving community to these dives.
Please consider your family both immediate and your dive family.
WE ALL WILL MISS YOU!
I have not witnessed a DCS incident but what I have researched and been TOLD it is horrible to experience.
Please consider these warnings and dive within your limits and training.
I am not trying to push anyone around but THINK before you dive!
Make good choices, LIVE TO DIVE ANOTHER DAY!

CamG Keep Diving....Keep Training....Keep Learning!

 

[theduckguru]

Beyond 60 ft is deep?

 

[VooDooGasMan]

Well not sure true bounce dive, yet your talking a single cylinder bounce, and you are correct maintain you safe ascent with an amount of gas supply to allow for deco, and 500 or more psi when surfacing.

 

[CamG]

I was making the point to NEW and not yet divers that the "deep rec. line is 60'".
For advanced or tech divers it would be quite a bit deeper but they would not consider doing a bounce dive in the first place.
Or should I say "hope" they would not!

CamG Keep Diving....Keep Training....Keep Learning!

 

[down4fun]

What is deep? Well anything that is over 60', past recreational limits, or simply beyond the personal divers training and or gas planning requirements.

A BOUNCE DIVE DOES NOT ACCOUNT FOR WHAT IFS!
I am assuming that a true BOUNCE dive is done on a single tank!

My purpose is simple, BOUNCE DIVES ARE NOT SAFE!

If you choose to do this type of dive then be very aware of what DCS is and how it kills those who violate the limits.

Please consider these warnings and dive within your limits and training.

Make good choices, LIVE TO DIVE ANOTHER DAY!

If you are new or old or not yet certified and drawn to the deep...I understand.

Good or bad I too was drawn to the deep. But there is a way to get there safely and that is through proper training, including gear selection and redundancy and experience. Diving is no different than any other group of people. There are different mind sets within the community and it's up to you who you follow. I hope you will make the safe choice and listen to those who deep dive safely through a proven and accepted means of training. And not follow the yahoos who actions have proven fatal to others.

I am not claiming to be some expert, but i do have little experience at this and there are countless others with way more experience than me who are willing to share our journey and knowledge so that others can get there safely, if that's your desired destination. And if you are one of the ones for whom the deep holds no intrest, that's kewl too. Dive on and be safe.

 

[Blue Sparkle]

My perspective is as a fairly new diver who has taken two different (and probably "typical") PADI OW classes (one when I was first certified in 2005 and one in 2009/2010 as a refresher).

I had a "good news/bad news" thought as I was reading your post.

At this point some of you will shudder at the mention of gas planning but a single tank does require planning and is taught in OW!

First, the "bad news." I think it would be a stretch to say that "gas planning" was taught in either of my OW classes. It was drilled in to us to check our SPG's early and often, and to be back at the surface with 500 psi, but as far as how to actually "plan" gas ahead of the dive... I don't remember any real mention of it. If it was there it was not emphasized.

I learned about gas planning here on SB (oh, it exists!), and then from reading further here and on linked pages written by SB members, and then from a one-day class with an instructor that I set up.

My purpose is simple, BOUNCE DIVES ARE NOT SAFE!

The "good news" is that a healthy respect of depths (and overheads) beyond our trained limits was absolutely drilled into us both times -- especially by the text. I actually had to expend some effort to "get over that" when the time was right to go deeper. I can't imagine getting any hint of a hint that it would have been okay to do a deep "bounce" dive.

Actually, if I could go back to OW class and wave a magic wand, I would remove some of the emphasis on "don't dive beyond your training" (not because it's not a good message, but because it was mentioned over and over again and is a simple concept), and I would in its place add gas planning (which can be used to good effect on the dives within our OW training).

My purpose here is not to say your message isn't good, but just to share my initial reaction --- as a fairly recent, "typical" OW student --- to two facets of your post.

I wonder how my experience compares to others' who took "typical" OW classes.

 

[redacted]

A BOUNCE DIVE DOES NOT ACCOUNT FOR WHAT IFS!
I am assuming that a true BOUNCE dive is done on a single tank!
I have read of several in the last month and will not mention any particular accident nor wish to demean any diver, agency, LDS that is not my purpose!
My purpose is simple, BOUNCE DIVES ARE NOT SAFE!

WHY? What is the difference between a bounce dive and any other dive done on a single tank that makes a bounce dive unsafe?

 

[eponym]

I think it would be a stretch to say that "gas planning" was taught in either of my OW classes. It was drilled in to us to check our SPG's early and often, and to be back at the surface with 500 psi, but as far as how to actually "plan" gas ahead of the dive . . . I don't remember any real mention of it. If it was there it was not emphasized.
[snip]
Actually, if I could go back to OW class and wave a magic wand, I would remove some of the emphasis on "don't dive beyond your training" (not because it's not a good message, but because it was mentioned over and over again and is a simple concept), and I would in its place add gas planning (which can be used to good effect on the dives within our OW training).

Nice post, Blue.

Here is one gas planning rule of thumb I use in OWD courses:

Don't plan to go deeper than the number of cubic feet of gas on your back.​

And here is one gas management rule of thumb I use in OWD courses:

With a single AL80, it's time to ascend when your tank pressure (in PSI) is current depth times ten, plus 300.​

Both these rules of thumb take into account the need to preserve a portion of "your" backgas for a buddy who runs out. As with all rules of thumb, their derivations are not as important as the ease of remembering and implementing them. And with increasing experience and knowledge one can begin to trade these rules for more detailed and more accurate plans.

 

[redacted]

Nice post, Blue.

Here is one gas planning rule of thumb I use in OWD courses:

Don't plan to go deeper than the number of cubic feet of gas on your back.​

And here is one gas management rule of thumb I use in OWD courses:

With a single AL80, it's time to ascend when your tank pressure (in PSI) is current depth times ten, plus 300.​

Both these rules of thumb take into account the need to preserve a portion of "your" backgas for a buddy who runs out. As with all rules of thumb, their derivations are not as important as the ease of remembering and implementing them. And with increasing experience and knowledge one can begin to trade these rules for more detailed and more accurate plans.

Unfortunately, that first rule is excessively conservative. The second rule could bring you to the surface with 300 psi which some might feel is a bit aggressive.

In this case, Rules are for fools. Learn and apply proper gas planning and neither rule is needed.

 

[FuzzyNutz]

WHY? What is the difference between a bounce dive and any other dive done on a single tank that makes a bounce dive unsafe?

Going down to 70-80 ft is not really all that different. Going down to 200... 300... 400+ feet is REALLY different.

I'm not a deep diver (130' max), so I'm not the most knowledgable on this, but it's pretty clear that: it's gonna take a while to get to the surface if something bad happens, air eventually becomes toxic, your tissues will load TONS of nitrogen, you'll be narced crazy, etc. And these are just some of the reasons keeping me above my limits until I have the necessary training and equipment to deal with those issues safely.