Crotch Strap in PSDs

[Stoy D Dabbs]

I am new on Scubaboard, This is my 2nd Post.

I notice on last thread on BCD Choice for PSDs.
I see teams are useing Backplate and Wing Setups.

I have been diving on our County Water Rescue Team for last 4 years, Our team members are volunteers, They supply there own equipment, There is no real standard, Except must have weight belts on.
I was also been interested in Tech Diving, so I started diving with Backplate and wing with doubles tanks. And then two years ago I started diving with single tank setup on the team.
I went threw GUE Fundamentals year ago last july, (got provisional).
The Only Objection I got was the Crouch Strap, That keep the Backplate from rideing up on the back.
They say it would keep the wight belt to be remove in a rescue.
Can sumeone tell me about the use of Crouch Strap in PSDs ?

[Gary D.]

First off welcome to the board.

For PSD I don't like a crotch strap. Seeing how we are right next door to each other we have like conditions so I would say no to the extra strap. It's just one more thing to deal with and we need to stay with KISS. As far as the weight belt it shouldn't matter as the belt BETTER be over that strap. But if you have to remove your gear the belt will have to come off as well. Not good in the great vis we have up here.

Again welcome aboard down stream.

Gary D.

[bridgediver]

There is no clear answer for this one.

I'm GUE trained as well as a PSD instructor so I knid of have a perspective on both as well. Alot of teams are gravitating towards the BP set-up as its very "robust" minimal and modular. Heres my take on both sides:

The BP evolved or was made popular by the DIR crowd - which is essentially a more advanced diver that dives usually with much more frequency than the average diver (and perhaps more than the average PSD) as such their skill set and equipment configuration is more refined (notice I didn't say better?).
One of the cornerstones of this rig is to dive a "balanced rig" with much more attention given to weighting than the average diver would do. When done properly they should have the ability to swim up their rig within 2-3ft of water with a couple of effortless fin kicks. They then maybeonly need to ditch 1-2lbs to get positive (or the weight of their light). Many will not even wear weightbelts and incorporate their weighting into fixed things like heavier tanks and BPs -- this is for drysuit diving only!
Wet suits are not really DIR as they have bouyancy swings and allot more ditchable weight is required -- you cannot "balance" a rig if wetsuits or a great deal of neoprene is worn.
Unless you have a really short BP and a longer torso a weightbelt over top of the crotchstrap may be uncomfortable and insecure - which is why you see people wearing the belts beneath.
Another option for the BP rig is to add integrated weight pouches but not my personal choice for PSD
For the BP to really do its job you have to have the crotch strap - it keeps everything stable and in place, not the shoulder straps

For the PSD, the biggest difference is that we usually dive 2-3lbs overweighted (some up to 5X more!) so our rig is already unbalanced. Being able to ditch the belt or more weight than becomes very important.
The easiest way to shed weight is the weightbelt - it is KISS as Gary said and we don't want a complicated system for PSD. The more complex and fancy things are the less likely you are to ditch as well.
The other eason why I don't like a BP for PSD is that on the surface (we spend allot of time on the surface) the wing will tend to tip you face down and so the diver will struggle with staying upright. Add a victim into the mix and the diver is exerting himself heavily which could lead to injury.
A standard jacket style BC affords both a weightbelt and good balance on the surface

the gear removal aspect is another good point (DIR guys would NEVER remove their gear but a PSD may have to someday)



Answer - they are 2 very different ways of diving so you probably need 2 different tools to do the job. I'd recommend BP for tech and jacket BC and weightbelt for PSD -- its what I do. I have tried to find a way to meld the 2 disciplines together for years and I can't find a way. Still in pursuit though...


wait till you tell your DIR buddies that you will be diving PSD without a buddy and use a pony bottle instead:D

[Anti-Hero]

I WISH my PSD team was diving BP/W systems. The charlie foxtrot PSD-centric BC's we use are a task loading, entanglement nightmare! They're also hard to clean, expensive to maintain, and are IMO very poorly designed.

[Rec2Tek]

The other eason why I don't like a BP for PSD is that on the surface (we spend allot of time on the surface) the wing will tend to tip you face down and so the diver will struggle with staying upright. Add a victim into the mix and the diver is exerting himself heavily which could lead to injury.
A standard jacket style BC affords both a weightbelt and good balance on the surface

the gear removal aspect is another good point (DIR guys would NEVER remove their gear but a PSD may have to someday)


Bridgediver
I have been told if I am being pushed forward, then My harness is not adjusted properly. So what is happening to you to cause you to go forward? No crotch strap?

[Gary D.]

Over inflating any back inflate BC can push you forward. Watch the inflation level.

Gary D.

[TC]

We're using weight harness systems so we wear those under the BP/W, crotch strap goes on top. There's a weight pocket on each side that pulls out. Takes a bit of adjusting in the pool to make sure everything is right but once it's dialed in it's comfortable and safe.

If your wing is pushing you face forward then some adjusting or weight realignment is needed. One thing I do is to put a 5 Lb. weight in a single weight pocket on my lower cam band. (On the opposite side from my pony so it helps balance that too)

[bridgediver]

Hi Rec2

If what you're thinking about is maintaining good horizontal trim while u/w then what you've been told is correct. What I'm refering to is when the diver is on the surface. Gary is quite right in the more air thats in the back inflate the worse it is but the characteristic will always be there no matter what volume of air is in the bladder.

As I said, a PSD may spend allot more time upright on the surface and performing tasks in this position. Most sport divers will spend very little time on the surface and if they are chances are that they are on snorkle - so they're horizontal, face down anyway.
So, if all of our bouyancy is on our back and up high (there is none on our front or sides) we will end up face down or horizontal the moment we relax -- this is perfect for a diver u/w as it puts you in the optimum diving postion; which is another reason why the DIR crowd insists on them. On the surface, not so good. Have you ever seen a PFD with all the floatation on the back?
Now the diver can overcome this effect by arching his back, and floating ontop of his back while constantly finning to keep the legs arched but this is a fairly limited postion for doing work on the surface AND it produces unecessary exertion. The more air in the bladder the greater the amount of effort.

Contrast this to the bladder on a jacket BC and most of the air will be all around the diver and lower on the body (also tends to bouy the diver up higher). Floating head up is allot easier

Try it for yourself in the pool. Get 1 of each type back inflate and jacket; inflate both and float in the water completely relaxed and see which one is better at keeping your face out of the water

I don't condemn BP and wing because I own a few of my own but its just something to think about - not my first choice for PSD

[dittrimd]

Great feedback by everyone. Here is my 2 cents. I dove a Zeagle Ranger on my PSD Team for 8 years before switching to a Halcyon. I immediately removed the crotch strap and have been quite pleased with the BC's performance.

As I understand it (I am not a tech diver) the Tec divers use the strap for two main purposes. One is scooter attachement which does not apply to PSD and the other is for better fit. It keeps the BC from moving around. I have to say that once I got my fixed harness adjusted correctly the thing does not move at all. That was one and only complaint I had about my Zeagle over time the straps would loosen and the BC would move around.

As for trim on the surface I always dive dry with my Viking. I use this as my primary bouyance control and keep my BC as a reserve. I agree with Gary when I have used my BC on the surface with proper inflation I have had no trouble keeping proper trim in any activity whether it be just floating or handling a victim.

Hope this helps.

Mark D.

[Gary D.]

Here is a pic of a couple of us very much upright with Zeagles on. I'm holding onto a gentleman we just recovered from 100' and he is over 250 pounds. I cropped it down to cover his face.

http://www.scubaboard.com/gallery/showphoto.php?photo=120012&nocache=1

Gary D.

[bridgediver]

yep, looks good Gary.
Like I said, it isn't impossible to stay upright but it does require work to do so - the more air you put into the bladder the greater the work but why not get a bladder where it requires no work at all? - ie a jacket BCD. Be honest now - Can you actually stay in a vertical position on the surface, even with a half filled back inflate bladder, without movement?
This is simple physics: air filled things float (back of diver goes up); not air filled things don't float (face and head of diver goes down)
I think you're missing my point


Looking at the picture (I don't know who's who) and please correct me if I'm wrong - I can only evaluate what looks apparent to me in the photo as I obviously wasn't there. The blue guy has very little air in his bladder and he might be holding onto the body with 1 hand at arms length so it doesn't look like much effort would be getting expended there. The red guy has a bit more air but again very little and it doesn't look like he's holding on to the body at all
Also something to note is look how low in the water the diver's heads are.
There is nothing "wrong" with anything in this picture but I'm the type of person always looking for the better mouse trap. Just because we've been using XYZ in past has never been good enough for me.
Why would you use something that you know you can't (or shouldn't)fill up completely? There will come a day when somebody does

:coffee:

[Stoy D Dabbs]

OK Thank You All For Responses.

Bridgediver: You have good Information.
Gary D: Yes need to keep it simple.
Dittrimd: You have A good Ideal.
Also thanks to: Anti Hero, Rec 2 Tek, TC

I was diving with BCD jacket, It was an old Scubapro that I got in 2001, It was A used rentail.
And sense than I had to put A coating of aquaseal on it to keep the air inside it.
It had seen its day.
Befor I gotten that BCD jacket, I was diving with Sub-Aquatic System back BCD for over 20
years, It had tendency put my face foward in the water.

I have to be sensitive with open mind with the use of BP/W on my PSD team.

Conclusion:
There is no clear answer on this yet.
BP/W should be dive with the Dry Suit.
I feel that A Dry Suit should not be use for BC, but redundant BC
Be cautious of weighting on BP/W.

[Mphill9929]

Since the stock market crash erase my retirement account, I can only offer once cents worth ...

I do not pretend to know all there is about diving and am always open to new ideas. I am a bit reluctant to buy advanced "techie" stuff but that is more resistance to change than anything.

I do not like rear inflation BCDs for Public Safety Diving. I do not like integrated weights either. I do like crotch straps on MY teams BCDs. Since it is late, I will make this short and we can discuss at length more later. MANY years ago we dove single hose regulators, rarely wore a weight belt, used steel 72s and if we had it - uses a WWII Mae West as a flotation device. To make it stay in place you HAD to use the crotch straps. 30 Years later I helped design a BCD specifically for Public Safety Diving. It was and still is one of the finest BCDs for the job I have ever see or used. It was made in the USA by Amersea. Amersea closed shop two years ago and we were unable to find a company willing to buy the BCD and put it in their catalog.

The Search 25 was purposefully designed for PSD work. One of the issues we satisfied by adding crotch straps was size differences between team members who might be sharing equipment. Because the crotch strap prevents the BCD from rising, they not only keep it a snug fit but also allow a smaller person to wear it without fear of it coming off. This allowed teams on limited budgets to (for example) buy 2 Mediums for three team members who wore medium and the one who wore a small.

As rough as we usually are on team gear, the added weights of an integrated weight BCD seem to cause the BCD to wear out faster. Plus we always seem to lose a weight pocket at the worst times and inmost cases revert to belted weights.

We purposefully avoid rear inflation. The short reason is if our diver goes unconscious and makes it to the surface, we want them floating face up - not pushed forward face down by a rear inflation BCD.

I like and appreciate that teams are finding multi task equipment and if you are training for worst case scenarios and are satisfied that your gear - not just your training - your gear is adding safety to your team then keep on doing what you are doing. But if you play "Worst Case Scenario" and multi task equipment is not helping to prevent accident, injury or death - then some thought needs to be done to figure out what can be added, deleted, altered or replaced.

Mark Phillips
Editor / Publisher
PSDiver Monthly
www.PSDiver.com

[buckidma]

some great post on this so let me weight in as a psd inst for years i have fought this battle in departments and mostly in my own sole. the bp is comfort and good looking and in certain conditions they should work as for the jackets the rite comfiguration and issues such as entanglement night mares go away. at this point i will not give you my choice but rather the way i made my choice and here are the questions i ask.
[LIST=1]
is it safe?
does it make sense?
will it work in a worse case senerio?
where will a diver float if unconsious
where will a divers eyes be in a backup position on surface will he be able to look down the line at all times.
The back up diver must be ready at all times to respond with every ounce of energy he can muster so if he spends that energy staying uprite is he giving his best if he is fatigued at the start.
where do I place tools lights ect...you must carry some tools with you and a well deigned pocket and proper hose routing and diver harness should lessen entanglement hazards.
if any psd wishes to discuss this topic off line i would welcome the comunication as i am always looking to learn . psd inst. b.buchanan

[Stoy D Dabbs]

Thank You for your Responses, I need to do some Research in the water this summer.