Mouthpiece Retaining Head-strap

Rickoz said:
Thank you for that link jptaylor9 :thumbsup:
Anyone got Pictures or Links to any of the others talked about :crossfing
Click to expand...

Here is the link:

Dräger Mundstück mit Kopfband | Online Shop | W+S Water Safety Europe GmbH | Seit 1999 (it works!).

Given the strong views by Paul and Dave on the subject, I would suggest they write to the UK Committee currently writing the new rebreather EU standard and suggest that a Crown Strap be provided with rebreathers.

The current standard requires one, but the new proposed standard removes such requirement (going against the overwhelming opinion of those who favour it in this thread).

I wrote to the EU responsible Committe in favour of the Crown Strap (and BOV and more)... but I was ignored. If you all write something to them, in addition to this very good thread on CCRX, maybe they will not remove the requirement from the next standard.

You can find details of how to do that here:

http://www.rebreathermallorca.com/video/poverosub/20100308DAN Letter.pdf

and here:

http://www.rebreathermallorca.com/video/YD/prEN14143 2010 Comments and Proposals Final IE-2.pdf

It is never too late to try to make your opinion count (although your comments might be dismissed on frivolous grounds or other CE technicalities).
 
gianaameri said:
Given the strong views by Paul and Dave on the subject, I would suggest they write to the UK Committee currently writing the new rebreather EU standard and suggest that a Crown Strap be provided with rebreathers.

The current standard requires one, but the new proposed standard removes such requirement (going against the overwhelming opinion of those who favour it in this thread).

I wrote to the EU responsible Committe in favour of the Crown Strap (and BOV and more)... but I was ignored. If you all write something to them, in addition to this very good thread on CCRX, maybe they will not remove the requirement from the next standard.
Click to expand...

Great idea worth considering
 
Paul Haynes said:
...a minor personal success was managing to raise the profile of the use of the mouthpiece retaining strap.
...
I do not pretend for a moment that a retaining strap offers a guarantee of survival, it simply provides mitigation against the risk of drowning by limiting the likelihood of you encountering it, thus increasing your chances of surviving a LoC event underwater.
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Here's Garspeed's example for you guys to ponder:

P6050006.jpg

P6050015.jpg


Matt.
 
I dived my Sentinel with the AP strap fitted this weekend.

Went fine.

To be honest in the water the strap wasn't noticeable, and on the surface kitting up etc, it wasn't that much of a pain either.

£15 well spent.
 
jackdiver said:
I dived my Sentinel with the AP strap fitted this weekend.

Went fine.

To be honest in the water the strap wasn't noticeable, and on the surface kitting up etc, it wasn't that much of a pain either.

£15 well spent.
Click to expand...

This one:

headstrap_650.jpg
 
matthewoutram said:
Here's Garspeed's example for you guys to ponder:

P6050006.jpg

P6050015.jpg


Matt.
Click to expand...

Thanks Matt. Used the AP one initially which is good value for money but found it a little bulky and realised that once length is set you don't need adjustment. Stole neoprene strap from oceanic stealth mask and made this one up which works fine (strap length just long enough!)

Cheers
Gar
 
If you are wearing a strap and you need to go to your bail-out then how does this work - do they just come away easy enough?

Sorry for my ignorance on gag-straps!

Matt.
 
I found that I can pull against the strap to get the mouthpiece out, but the most comfortable method in normal use is to slide the strap over the top of my head before taking out the mouthpiece.
 
matthewoutram said:
If you are wearing a strap and you need to go to your bail-out then how does this work - do they just come away easy enough?

Sorry for my ignorance on gag-straps!

Matt.
Click to expand...

You can simply pull mouthpiece out from front which may or may not break o-rings (that's what they are there for) but I grab straps at side and pull forward to remove from back to front as the neoprene has enough stretch to allow this easily. Then you can let loop float up or push down as you prefer whilst firing up bailout reg.

Cheers
Gar
 
jackdiver said:
I dived my Sentinel with the AP strap fitted this weekend.

Went fine.

To be honest in the water the strap wasn't noticeable, and on the surface kitting up etc, it wasn't that much of a pain either.

£15 well spent.
Click to expand...

Pleased to hear it went well; spread the word.

Rgds paul
 
jackdiver said:
I dived my Sentinel with the AP strap fitted this weekend.

Went fine.

To be honest in the water the strap wasn't noticeable, and on the surface kitting up etc, it wasn't that much of a pain either.

£15 well spent.
Click to expand...

I went to the Draeger strap. Absolutely fantastick. And YES i can say that it is noticiable the diference.

Last wednesday i did a 120 minutes dive and i did not have any pain in my mounth.

I think that the APD one it is not strong enaught to hold the weight of the BOV.

Best
Mikel
 
Seems plenty strong enough for mine...

:)

Oh, one of the reasons why I felt no differance in the water is that my mouth piece is comfortable to start with.
 
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Ok so I tried the drager strap out on my bov over the weekend. Worked great, I even took off the strap during the dive to see the difference and noticed it has the added benefit of keeping the normally exposed upper lip warm during the dive.
 
Paul Haynes said:
Hi All

Today I was advised, I hope incorrectly, of the very sad news of a very recent rebreather fatality whereby a solo diver using a DPV in a cave knocked his head causing Loss of Consciousness, subsequently resulting in death by drowning.

First of all my apologies if I am referring here to a family member or friend in such impersonal terms, I don't mean to but the only information I have is what I have recited above, which may well be inaccurate. If it is true, it is again another very sad loss and so without wishing to appear insensitive, whilst avoiding the subjects of solo diving and the wearing of helmets with a DPV in an overhead environment, I thought I would start a dialogue on a subject I have been an advocate of since my very first days of rebreather diving some 22 years ago - that of the use of a mouthpiece retaining head-strap.

For those who may not have read a paper I wrote last year titled A Survival Guide To Rebreather Diving (available from the downloads section of Haynes Marine Ltd web-site) I have pasted the paragraph on this subject below and would be interested to hear what the current consensus is amongst the membership.

Rgds

Paul

Mouthpiece Head-Strap
Looking at rebreather incident reports and in particular the excellent rebreather fatality analysis undertaken by Diver’s Alert Network (DAN), although the triggering events and the problem that disables the diver are perhaps most important in understanding accidents and how to prevent them, the fact remains that in most cases the eventual cause of death was drowning. In at least some accidents a disabling problem (such as an oxygen toxic seizure) might not have led to drowning if the diver had been wearing a mouthpiece head strap.

Unless used with a full face mask, every military rebreather I can recall, both of classic and contemporary design, uses a mouthpiece retaining head-strap. The reason for this is simple, in the event of Loss Of Consciousness (LOC) there is a reduced likelihood of dropping the mouthpiece and of subsequently drowning. In other words a simple strap, similar to a mask-strap, secured to the mouthpiece, when worn correctly increases the chances of surviving the most common cause of rebreather deaths. Yet it appears that its use is resisted by both sport rebreather manufacturers and the majority of non-military rebreather divers I have discussed the matter with.

Having a military rebreather diving background, I have been conditioned to use a rebreather mouthpiece retaining head-strap from day one of my rebreather diving career. I continue to do so and I encourage my students and diving buddies to do so. Besides its obvious potential benefit should you fall unconscious, a mouthpiece retaining head-strap relieves the physical effort and resulting jaw fatigue of having to hold the mouthpiece for extended periods. In contrast to common misconception, when removed, pulled down and placed on the upper chest, the use of a mouthpiece retaining head-strap does not prevent or hinder the quick removal of the mouthpiece should you need to switch to an open circuit bailout demand valve.

Thirty years ago in the UK, there was considerable resistance from the motor industry and the motoring public to a proposed new law to make the use of car seat belts mandatory. Thankfully, despite this resistance the law came into force and driving accident fatalities immediately dropped by a significant amount. Today very few of us would consider setting off in a vehicle as either a driver or passenger without wearing a seatbelt, the use of which has become part of driving safety culture.

In my opinion it is likely that the rebreather fatality list would not be so long had the use of a mouthpiece retaining strap been common practice. Again I say be a thinking rebreather diver, use a mouthpiece retaining strap and the probability of encountering the hazard of drowning, the single largest cause of rebreather fatalities, will be reduced.
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Hi All

This post has now had over 8000 viewings and so appears to have raised quite a lot of interest amongst a membership of just over a 1000. However despite the interest shown, because the topic is a rebreather safety crusade of mine, I'd like to re-energise the thread.

By now most of you will have read Mike's courageous post about his hypoxic loop experience on the lessons learnt forum. Ceasing to exist is just one mistake away for all of us who enter an alien environment. I make no judgement on Mike other than to thank him for having the courage and integrity to share the experience with us so we can all learn from it. I'm sure the vast majority of the membership share the sentiment.

I believe the general scenario Mike found himself in, common to a number of rebreather incidents, some unfortunately fatal, is a great example of where a mouth piece retaining strap can make the difference between surviving an incident or not. Whilst swimming at the surface, Mike was sufficiently self aware of something not being right to look at his hand display; PO2 0.1 bar! Unconsciousness was likely seconds away. Good fortune was on Mike's side that day, a likely and alternative physiological hypoxic response might have been a feeling of well being as he peacefully slipped into unconsciousness oblivious to his PO2.

Bearing in mind you can drown / asphyxiate face down in a puddle, let us then consider a diver in this situation and assume Loss Of Consciousness (LOC) and the diver is positively buoyant. A mouthpiece retaining strap, if worn correctly, will prevent that mouthpiece from being dropped. As a consequence the airway and breathing loop are wholly or partially protected from flooding, likely providing sufficient time for the diver's situation to be comprehended by those around and an effective rescue implemented (this could be many minutes if swept away in the tide from a buddy / safety boat). If the diver was negatively buoyant he/she would cease to fin and as a result begin to sink. The PO2 would quickly rise to the point where consciousness would be regained. Because the diver has not inhaled water and because the breathing loop has not flooded, the diver is now potentially given a second chance of life through the implementation of self rescue or a buddy has been given time to initiate an effective response. The probability of a positive outcome has now been increased.

Lets now look at the alternative and let us assume no mouthpiece retaining strap is used, the very likely scenario now is the mouthpiece is dropped as the diver relaxes into unconsciousness. If face down, the next inhalation will be water and asphyxiation will quickly ensue. Even if positively buoyant, face down in the water for a few minutes will most likely result in death or brain injury. If the diver is already negatively buoyant, the situation is of course now much worse, the descent rate accelerates as the loop / lungs vent gas, which is replaced by water, along with of course Boyle's law acting upon every other gas space, which the unconscious diver is unable to compensate for. The diver will likely be lost and the probability of surviving this incident has now significantly diminished; all for the sake of failing to use what can be in it's simplest form, a $10 rubber mask strap.

As I keep saying, there are no guarantees here, however hypoxia is one of, if not the largest rebreather disabling injury and drowning is by far the single largest cause of death in rebreather fatalities (it's over 90% of cases according to DAN research). By putting a simple measure in place to protect both the airway and breathing loop from water ingress in the event of LOC, will significantly increase the likelihood of delaying drowning and loop flooding thus potentially providing either yourself or a buddy the opportunity or additional time to implement a rescue.

For those then who do use, or have started to use a mouth piece retaining strap, please let us know how you have got on so new members can learn from your experience. Also if you have ceased to use a mouth piece retaining strap or refuse to use one, again please let us all know why so we can discuss your reservations.

2013 - The Year Of Rebreather The Mouthpiece Retaining Strap?

Come on CCRX, together we can do it ;-)

Rgds Paul
 
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