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Rebreather Fundamentals

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					BSAC Full Face Mask (FFM)
      Experience




Using a Full Face
     Mask
        BSAC FFM
        Experience    FFM Experience outline

          Theory Workshop
           • Advantages of a FFM
           • Fitting a FFM
           • Precautions to be taken
          Dry workshop
           • Practice fitting and removal
          Pool session
           • Work in pairs (usually)
           • 1 mask per pair
           • Rota system
          Be ready in shallows
FFM.1
06/07
        BSAC FFM
        Experience               Aims


              What is a Full Face Mask?
              Why use a Full Face Mask?
              Using a Full Face Mask
              Precautions




FFM.2
06/07
        BSAC FFM
        Experience             What is a FFM?


          A full face mask (FFM) encloses the
          whole face
           • Eyes, nose and mouth!
          Most FFMs are divided into two
          halves
           • A mask
                – provides an air space for the eyes
           • An oro-nasal pocket
                – allows you to breathe through
                  mouth or nose
                – reduces the “dead space” volume
                – prevents build up of carbon dioxide
FFM.3
06/07
        BSAC FFM
        Experience             Why use a FFM?

          Allows natural nose and mouth
          breathing
            •   Less stress
          Communications
            • Diver to Diver e.g. for monitoring
            • Diver to Surface e.g. aids project work
          Insulation from cold or polluted water
          Breathing supply secured through
          mask
            •   Less jaw ache on long dives
            •   Gas supplied in event of blackout
FFM.4
06/07
        BSAC FFM
        Experience   Parts of a Full Face Mask


   Face plate



   Regulator



FFM.5
06/07
        BSAC FFM
        Experience   Parts of a Full Face Mask

                                        Nose
                                        block
   Skirt


    Spider



FFM.6
06/07
        BSAC FFM
        Experience               Fitting a FFM

          Correct fitting and adjustment key to:
            • Comfort
            • Preventing leaks
          Demist using antifogging agent.
          The cup of the spider should be positioned so it
          sits at the back of the head, below the crown.




FFM.7
06/07
                Incorrect               Correct
        BSAC FFM
        Experience            Fitting a FFM

          Normally accomplished by
          tightening the bottom straps
          first….


                 …then working the way up.




          PRACTICE before use.
FFM.8
06/07
        BSAC FFM
        Experience        Releasing a FFM

          Most masks have quick release buckles on
          lower straps.
          Pull mask up and away from face, use thumbs
          to release straps.




          PRACTICE before use.
FFM.9
06/07
         BSAC FFM
         Experience            Dry Workshop



           Practice Session
             •   Work in pairs
             •   Ensure air is on or regulator is removed!




FFM.10
06/07
         BSAC FFM
         Experience                Precautions

           Mask malfunction
             • Practice clearing a flooded mask
             • Carry spare half (normal) mask and AS
           Alternative Supply
             • In case own mask floods
             • For buddy - sharing FFM not practical
           Carbon dioxide build-up
             •   Caused by poorly fitted/vented mask
             •   Hypercapnia
           Increased air consumption

FFM.11
06/07
         BSAC FFM
         Experience           Hints and tips


           Take time to ensure a good fit
           Practice fitting and releasing until
           competent
           Check for leaks in shallows
           Equalisation method depends on mask
            • Pinch nose as normal (Scubapro) OR
            • Push whole mask against face until nose
              block blocks nose!


FFM.12
06/07
         BSAC FFM
         Experience                 Summary



         Why use a Full Face Mask?
         Parts of a Full Face Mask
         Fitting a Full Face Mask
         Releasing a Full Face Mask
         Precautions



FFM.13
06/07

				
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