Full face mask and Co2

[idiot fish]

Hi Guys,

I am using a full face mask with my YBOD. The mask (Kirby Morgan Supermask) retains the normal mouthpiece bite in my mouth so when normally diving the deadspace is the same. However I was wondering if it possible to use the mask without the mouthpiece held in the mouth i.e. just taking it out the mouth but keeping mask on of course, the FFM will keep me dry.

I have heard talk about 'deadspace' in regulators and FFM.

Is this a real issue or a myth?

How do other FFMs work - especially when using comms? Do they all retain the mouthpiece bite in the divers mouth?

If deadspace and CO2 build up in it is an issue should I worry about fitting a OC/DSV to a YBOD or a FFM??

Any feedback would be appreciated.

[padiscubapro]

idiot fish once bubbled...
Hi Guys,

I am using a full face mask with my YBOD. The mask (Kirby Morgan Supermask) retains the normal mouthpiece bite in my mouth so when normally diving the deadspace is the same. However I was wondering if it possible to use the mask without the mouthpiece held in the mouth i.e. just taking it out the mouth but keeping mask on of course, the FFM will keep me dry.

I have heard talk about 'deadspace' in regulators and FFM.

Is this a real issue or a myth?

How do other FFMs work - especially when using comms? Do they all retain the mouthpiece bite in the divers mouth?

If deadspace and CO2 build up in it is an issue should I worry about fitting a OC/DSV to a YBOD or a FFM??

Any feedback would be appreciated.

with most FFM dead air space is definately an issue, besides this most mask are kept from fogging by the fresh dry gas being directed across the face of the mask, in a rb this definately is not the case.

I haven't seen the RB pod you are using but my GUESS is that the air space is small enough not to be of concern since its an isolated pocket..

[rmediver2002]

http://www.kmdsi.com/products/FAQ.html

This mask was designed with two seperate air spaces, one for the POD and one for the view port. One of the primary function this mask was designed for is rebreather use.

Deadspace is not signifigant even without using the bitepiece.


There are only a couple versions of full-face mask available that utilize a mouthpiece, it really defeats much of the advantage of a FFM...

http://www.adp.fsu.edu/HistoryOfDiving/index.html

couple different versions are listed here...

Jeff Lane