Teaching of SMB/Safety Sausage Deployment in Basic Scuba training

[Blackwood]

If my understanding is correct, you should be able to fill a safety sausage (with no over-pressure relief valve) 3/4 full and deploy it from 15ft (~5m) without rupturing it.

Depends on well it was made, I suppose. That would represent about 8% overstrain. Probably within margin, but who knows?

 

[Blackwood]

Managing the task loading of the bag shoot and controlling my buoyancy and spooling up the line and keeping track of my buddy and monitoring my ascent rate and handling my stops . . . it was absolute chaos, and several times resulted in me losing control, shooting to the surface, and ending up there covered in line and laughing hysterically. (Note: All this practice was done in very shallow water.) I don't even want to THINK about what would happen if you turned people in their OW class loose with something which floats and something which contains a great deal of malignant, autonomous cave line.

Sure, but if a diver in a non-classroom environment (i.e. real diving) started struggling with the additional task of spooling up, he/she could simply lock it, go up the line, and then pull it up.

Numb hands have caused a few dropped spools within my dive group. Dealing with the line at the surface is annoying, but I suppose better than the alternatives.

 

[Splash-X]

Depends on well it was made, I suppose. That would represent about 8% overpressure. Probably within margin, but who knows?

Not to sound stupid or question your math, but what formula did you use to calculate 8%? Assuming that 15ft is 1.5 atm. of pressure, the sausage 3/4 filled would expand to 1.5 times that, or 1.125, which is roughly 12 - 13%

Thats pretty close to your 8% so I just wonder what formula you used so I might gain a better understanding of it.

 

[The Chairman]

I teach it in AOW ... primarily because that's where we are exposing divers to more challenging conditions where a deployable SMB could be useful.

Me too. This is part and parcel a part of problem solving at depth.

I am at the end of my dive and near to my NDL. I just lost my buddy with the flag. What do I do? Blow off my deep stop and 5 minute Precautionary Stop and ascend? Nope. It's time for plan "B". Now the boat captain knows he has one or more divers separated from the flag.

 

[Blackwood]

Not to sound stupid or question your math, but what formula did you use to calculate 8%? Assuming that 15ft is 1.5 atm. of pressure, the sausage 3/4 filled would expand to 1.5 times that, or 1.125, which is roughly 12 - 13%

Thats pretty close to your 8% so I just wonder what formula you used so I might gain a better understanding of it.

You're doing scuba math and I'm doing calculator math, so your 1.5 is my 1.45.



[1+(15/33)]*.75=1.09 (the 8 was a typo).

 

[CamG]

Greetings Bluefabian and that was very unfortunate that it was never discussed or brought up during your OW. It was discussed right after the reason we were seeking training. He explained that it was not a part of our Padi training but offered to do a extra dive with us. Since we followed OW with AOW we had bag blowing practice for the Search and Recovery and it was great.
On the flip side I know what TSandM is talking about very well. I found myself in a like situation on Lake Huron. I find humility to be a great teacher and motivator!
I would find it very useful information to share with your instructor what and where you are planning to dive and ask for specific help with surface marker deployment.
If diving from a boat in the ocean or lake it is a must! In my opinion it would and should be a priority in the beginning dive skills. It is a great way to practice at the end of dives and making your safety stop. It is best to train in a safe environment under a watchful eye not necessarily an instructor but a more experienced buddy etc.
I assure you it will be a experience the first time. But that is why it is important to practice and train. Mastery takes time and discipline.
Good luck and ignorance is not an excuse, it is suicide. This skill can and will save your life in a emergency situation.
CamG Keep diving....keep training....keep learning!

 

[Splash-X]

You're doing scuba math and I'm doing calculator math, so your 1.5 is my 1.45.



[1+(15/33)]*.75=1.09 (the 8 was a typo).

I rounded which accounts for my higher number, but either way we were on to the same formula.

 

[Steve50]

I teach OW to have an SMB and audible signal device to use at the surface....deployment of SMB from depth to AOW and any other cont.ed. diver beyond AOW who has not already had the experience...

 

[drivsea]

For OW students the use of safetysausages (surface deployment) would be quick and easy to teach, and encourage students to purchase this simple piece of safety gear (some even include a whistle). For the OP this could have increased the chance of being seen in rough seas etc.
SMB deployment at depth should probably be taught in shallow water before conducting dives that require a safety stop (deep diver specialty at the AOW level), and be mastered before dives with deco.