Oral Nasal Mask; Oral Nasal Mask Removal; Inspection Of Oral Nasal Mask; Oral Nasal Mask Replacement - Kirby Morgan KMB-18 A/B Operation And Maintenance Manual

KMB 18 & 28 MANUAL
6.15

ORAL NASAL MASK (9)

Fig. 6.66 The oral nasal mask.
6.15.1 Oral Nasal Mask (9) Removal
Tools Required:
7/16 inch Open End Wrench
The oral nasal mask (9) is easily replaced.
1) Remove the nose block device (3) first. See
Section 6.3.2.
2) Remove the oral nasal microphone (12).
3) The oral nasal mask (9) can then be pulled off
the regulator mount nut (8). It is held on by a snap
fit.

6.15.2 Inspection of Oral Nasal Mask (9)

1) Inspect the oral nasal mask (9). If it is torn or
rotting it must be replaced.
2) Inspect the oral nasal valve (5). If it is torn or
rotting it must be replaced.
6.15.3 Oral Nasal Mask (9) Replacement
1) Snap the oral nasal mask (9) back over the
regulator mount nut (8).
2) Reinstall the microphone (12).
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© Copyright 1970-2003 Kirby Morgan Dive Systems, Inc. All rights reserved. Document # 010518001
3) Reinstall the nose block device (3) as per
Section 6.3.3.

6.15.4 Oral Nasal Valve Replacement

1) Remove the valve body (53) by pushing it
out of the oral nasal.
2) Remove the old valve (52) by pulling it out.
3) Install the new valve by feeding the thin tail
through the valve body and pulling on it until
the valve is seated.
4) Install the valve body in the Oral Nasal. The
valve MUST be on the inside of the Oral Nasal.
DANGER: The oral/nasal valve must
be replaced correctly to provide gas flow in the
proper direction. The flow through the valve
must be from the interior of the helmet into the
oral nasal mask. This will allow the diver to
breathe the gas from the defogger valve freely,
yet help to reduce carbon dioxide inside the
helmet. If the valve is not replaced properly
this could make it difficult to breathe the gas
supplied by the defogger and expose the diver
to an excess of carbon dioxide. This could lead
to exhaustion and blackout.
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