PADI OW and BPW

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

Eric Sedletzky

Contributor
Messages
7,523
Reaction score
6,244
Location
California
# of dives
500 - 999
Any instructor teaching in the same relative conditions over and over again year after year should eventually have some sort of clue about how divers should be weighted. I’m sure most students are renting the stuff from the shop so it’s not like it’s a big mystery to the instructor what their gear is going to be.
I’ve taken people on demo dives in my neck of the woods (50 degree water) who bought BP/W from me. Most wore jackets prior and this was their first BP/W experience. How is it that I can get them to within a lb or two even before we hit the water just by looking at their suit and body composition, and I’m not even an instructor.
An instructor deals with this a hell of a lot more than I do on a regular basis, so what’s the excuse?
 

wetb4igetinthewater

Instructor
ScubaBoard Supporter
Scuba Instructor
Divemaster
Messages
6,562
Reaction score
5,092
Location
Seattle
# of dives
500 - 999
If we measured the diver's buoyancy, and their gear's, and their wetsuit's in the pool and all those items weights on the pool deck, and we did the math, how far off could we be? Drysuit in this case. And we had done this with 10 prior students.
Where in God's name did I state that the student's gear and exposure protection should be measured in a pool?

Did I not write how I performed the measures of the scuba kit using a rowboat? When is the last time you've seen a rowboat in a swimming pool? I'll concede that I wasn't as clear about the wetsuit using a mesh bag to contain it and then add weights to an attached weight bag to determine a rough estimation of its buoyancy (which I clearly stated would be a little high). Though now that I think about it, it would be interesting to try the buoyancy of the wetsuit in a pool and see how that works, as the lower density of fresh water would result in a lower number, how this would be offset by the higher number from it not being worn (stretched) and compressed (surface vs 15 feet) would be interesting.

The point is that this only needs to be done ONCE per wetsuit (though wetsuits from the same manufacturer/size/thickness could be grouped together). Same with the scuba kit. Do it ONCE with the largest and smallest BCD used at the shop, and use an average for everything in between (though I doubt it will differ by more than a pound).

The number for the scuba kit is spot on as that doesn't' change with depth. The number for the wetsuit determined in salt water will be a tad high. This will be slightly compensated from the measurement to get the student to sink in a pool, as it would be slightly higher in salt water. This should be addressed at the end of the first open water dive. OW2 should be dialed in

Now if the student is in a dry suit, then you don't have the same problem with students getting cold as you do dry suit. There's no excuse for not properly weighting a dry suit student other than laziness or ignorance. When i started teaching, all of our students were in dry suits, but we weighed them without their scuba kit and we were told by "our betters" that the scuba kit with a steel 80 at 500 psi would be neutral (it isn't as I determined later).

Don't you and @tursiops realize that that I'm trying to address the reality that is industry wide? This isn't PADI specific. Sure, I'm attacking PADI here, but also SSI, NAUI, SDI, heck, even RAID for allowing students to be placed on their knees. This is an industry problem. Full stop.

That's the whole reason why I submitted a blog series on my way for teaching neutrally buoyant and trimmed. There are of course other ways of course. Probably better ways. The only thing that matters is that students have their weights distributed so that they are effortlessly horizontal and that they only have enough weight to keep them at their safety stop with nearly empty cylinder and empty wing/BCD. I don't care how all open water students all over the world get there, just that they do. Maybe I'm unaware of material that your agency provides students with specific advise on how to accomplish proper weighting (including trim). If that is the case, show me, as I'm always listening.

An instructor deals with this a hell of a lot more than I do on a regular basis, so what’s the excuse?
$50 max per student. That's only if the student gets certified (so there is incentive to not be too stringent). That's why they pack them in as much as they can. Get 2 assistants, and you have 12 people. That's $600 for (this is a rough guess for these classes) for 40 hours work (probably more hours). That's $15/hour. Subtract equipment expenses, insurance, wear and tear on your car, agency dues, and the compensation becomes much less.

Now if you have "only" 8 students in your class, that's $400, so $10/hour, minus the same expenses distributed throughout your courses.

Split a class with someone, so you get paid for fewer than 8 students, and you are working for less than minimum wage.

So that's the excuse. No incentive. The only people that go above and beyond don't care about compensation or have goals to open their own dive center. But I have heard more than once that putting in more effort just isn't worth their time due to the low pay.

I've always provided gear to students to compensate for what they received from the shop. From Apollo neck/wrist seals, to semi-dry gloves, to masks, to marigolds. I just tried to make their class as good as I could. Though I remember once class where I gave the student marigolds (pullover rubber gloves). The dry suit leaked really badly, and the only thing that was dry was his hands.
 

MichaelMc

Working toward Cenotes
ScubaBoard Supporter
Messages
2,316
Reaction score
1,537
Location
Berkeley, CA
# of dives
100 - 199
You were very clear on it being a rowboat, which I did take as not in a pool. Your method is very clear to me. I measured my wetsuit years ago with a mesh bag in the pool. Standing with a scale at an immovable poolside, or dockside, seems easier than in a rowboat. You just also need the land weight if done in freshwater. (ETA: To do 'if an object is neutral in fresh, and weighs x on land, how much must it weigh on land to be neutral in salt.) But either way is fine. And yes, if all students get kit from the same set of gear, you only have to do it once.
 

wetb4igetinthewater

Instructor
ScubaBoard Supporter
Scuba Instructor
Divemaster
Messages
6,562
Reaction score
5,092
Location
Seattle
# of dives
500 - 999
You were very clear on it being a rowboat, which I did take as not in a pool. Your method is very clear to me. I measured my wetsuit years ago with a mesh bag in the pool. Standing with a scale at an immovable poolside, or dockside, seems easier than in a rowboat. You just also need the land weight if done in freshwater. (ETA: To do 'if an object is neutral in fresh, and weighs y on land, how much must it weigh on land to be neutral in salt.) But either way is fine. And yes, if all students get kit from the same set of gear, you only have to do it once.
I'm sorry too, as I thought I was responding to someone else.

What is so frustrating to me is that John's article (he was the driving force according to Peter) was published ten years ago! And look how slowly progress has come!

This is a critique of the entire industry. I haven't gone through all of RAID's materials that they provide for free online, I will say their Instructor Playbook is a HUGE step in the right direction, though I think some parts regarding buoyancy/trim could be improved. I've attached the version I have for the benefit of anyone who hasn't seen this, both instructor and non-instructor. I think every IDC candidate of all agencies should take a look.
 

Attachments

  • RAID_INSTRUCTOR_PLAYBOOK_V1.5_Feb_1_2021_C.pdf
    2.6 MB · Views: 46

MichaelMc

Working toward Cenotes
ScubaBoard Supporter
Messages
2,316
Reaction score
1,537
Location
Berkeley, CA
# of dives
100 - 199
No worries on the mixup.

I would love to have a diagram in all OW texts of a diver at 45 degrees with up-down arrows for mass and buoyancy/volume. Then a second with some lead shifted to move some of the down arrow to the shoulder or high back and the diver level. Plus a diagram of vertical and horizontal drag for 45 and horizontal divers. And one of the direction of kick thrust.

ETA: Maybe component arrows for diver, fins, tank, BC, and lead and an aggregate arrow for volume and mass centers. Some of the lead shifts, splitting a lead arrow and moving the new one higher up the body. That shifts (mostly) the aggregate mass arrow, making the aggregate arrows originate in nearly the same place. Making any orientation easy to achieve. We have those diagrams for buoyancy in OW texts. We do not have them for understanding and achieving a neutral weight distribution.

ETA2: You could simplify to component arrows for just diver, fins, and ballast. Less clutter that way for the wide-eyed overloaded OW student. Yet you still get in weight distribution and dynamic changes via leg extension/retraction.
 

wetb4igetinthewater

Instructor
ScubaBoard Supporter
Scuba Instructor
Divemaster
Messages
6,562
Reaction score
5,092
Location
Seattle
# of dives
500 - 999
No worries on the mixup.

I would love to have a diagram in all OW texts of a diver at 45 degrees with up-down arrows for mass and buoyancy/volume. Then a second with some lead shifted to move some of the down arrow to the shoulder or high back and the diver level. Plus a diagram of vertical and horizontal drag for 45 and horizontal divers. And one of the direction of kick thrust.

ETA: Maybe component arrows for diver, fins, tank, BC, and lead and an aggregate arrow for volume and mass centers. Some of the lead shifts, splitting a lead arrow and moving the new one higher up the body. That shifts (mostly) the aggregate mass arrow, making the aggregate arrows originate in nearly the same place. Making any orientation easy to achieve. We have those diagrams for buoyancy in OW texts. We do not have them for understanding and achieving a neutral weight distribution.

ETA2: You could simplify to component arrows for just diver, fins, and lead. Less clutter that way for the wide-eyed overloaded OW student. Yet you still get in lead distribution and dynamic changes via leg extension/retraction.
Those are great ideas. I think I’ll incorporate those into my blog series and if modifications, I’ll add that. Fiverr, here I come.
 

KenGordon

Contributor
Messages
4,049
Reaction score
2,872
I taught almost all of my rescue diving courses to students in jacket BCDs and while wearing a jacket BCD. The surfacing victims always went face down. Its the way an inert body tends to go. A jacket BCD will not push you forward onto your face as fast as an overfilled back inflate model, but it is not going to put you on your back.

Try it yourself. While ascending in an open area where you aren't going to scare the locals, let you body go limp for the last 10-15 feet and see what happens.
This was the argument against stab jackets made by ABLJ people when stab jackets were the revolutionary new thing. There are probably paper newsletters with cutting edge divers complaining that the shops wouldn’t carry the new fangled stab jackets because all the shopkeepers were old fashioned stick in the muds.
 

Eric Sedletzky

Contributor
Messages
7,523
Reaction score
6,244
Location
California
# of dives
500 - 999
This was the argument against stab jackets made by ABLJ people when stab jackets were the revolutionary new thing. There are probably paper newsletters with cutting edge divers complaining that the shops wouldn’t carry the new fangled stab jackets because all the shopkeepers were old fashioned stick in the muds.
What is “ABLJ”? never heard that one yet.
Is there an ABLJ community? lol.

Have you ever used an actual original orange Scubapro Stability Jacket?. I have, they sucked!
I had two of them given to me by someone who never used them.
They had a plastic back pack that was sewn into the fabric in the back with no actual webbing or strapping going through any of the pack slots at all, the pack just sat there. They must have used up a bunch of plastic packs to make Stab jackets because the pack was identical to what was the Healthways pack. The tank strapped to the pack with a single tank strap. The plastic pack or plate was attached by being sewn into a place on the back and held on by a bunch of nylon fabric and it was a floppy mess. There was no way to cinch it up and the pack never rode in the right place on your back because it was moving all over. Worst design I ever saw. Dacor had a similar one and it was even worse because the plastic pack was even more awkward. I had one of those too and all of it ended up on the trash. Even the vintage community didn’t want it.

That whole warped sewn up floppy jacket BC concept was forced on the dive community by the manufacturers and the dive shops. I am really glad to see that divers are finally taking charge of their gear choices once again and choosing alternatives like BP/W, no thanks to dive shops and main line manufacturers; it took the internet and a handfull of rogue equipment makers to break it free from that.
I can say that I’m also proud to be a part of that.
 

Ucarkus

Contributor
Messages
363
Reaction score
216
Location
Berlin, Germany
# of dives
1000 - 2499
What is “ABLJ”? never heard that one yet
Strange.. I have certified my wife in 2009, below picture is from her owd manual.

D1FC4F26-197E-43B9-9B56-F14859FA3938.jpeg
 

wetb4igetinthewater

Instructor
ScubaBoard Supporter
Scuba Instructor
Divemaster
Messages
6,562
Reaction score
5,092
Location
Seattle
# of dives
500 - 999
Strange.. I have certified my wife in 2009, below picture is from her owd manual.

View attachment 647577
Yeah, in pink it says "past and present". The past part is referencing the "front-mounted" style. Sure, there is an occasional dinosaur still diving one of these, but the last sentence in my original manual states: "Of these, crecreational divers by far most commonly use the jacket style."

Question, when you certified your wife, did she use a ABLJ? If you are associated with your shop, does your shop still train new divers with these?

We should be realistic on what divers are being trained with today. I only see new divers being trained in jacket style BCDs and BP/Ws. If there is any instructor/shop that uses ABLJ in their open water courses, I'd sure like a link to their website, as I won't believe it until I see it.

After all, PADI did remove such images in their 2015 open water manual. After a quick skim, I just see jacket style BCDs being shown. There is a discussion on sidemount on page 51.
 
https://www.shearwater.com/products/teric/

Top Bottom