Kirby Morgan 77 - Manual (Page 20)

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© Copyright 1970-2008 Kirby Morgan Dive Systems, Inc. All rights reserved. Document #080626002
Kirby Morgan 77
from inverting the helmet exhaust valve when hitting
the water.
The diver must report to the surface immediately
after the entry. It is a good policy to descend 10 or
20 FSW (3-6 MSW), pause and check the regulator
adjustment knob to ensure adjustment for the least
breathing resistance.
The purpose of this adjustment knob is to allow the
diver the ability to compensate for variations in um-
bilical supply pressure. This adjustment device oper-
ates by simply increasing or decreasing the amount
of spring bias tension on the demand regulator inlet
valve.
This adjustment device is not intended as a minimum-
maximum device. Minimum and maximum applies to
supply pressure only. The adjustment knob should be
adjusted by the diver to be at the easiest breathing
setting at all times.
Diving a KMDSI helmet or band mask with a bias
setting greater than that just necessary to keep the
demand valve from free flowing increases the work of
breathing and reduces the diver’s ability to perform
heavy work.
Then the diver checks in with the surface before
descending to the job. If a closed bell is being used,
the diver enters the water from the bell and pauses
for a short time outside the trunk until he is sure all
systems are operating properly.
During the decent the communications must be
checked again and the diver supply pressure should
be adjusted as necessary to maintain the required
over-bottom pressure. It may be necessary for the
diver to readjust the demand regulator by means of the
adjustment knob once at the work site to compensate
for the variation in umbilical supply pressure.
3.11 Emergency Procedures
3.11.1 Flooding
In the event of partial or complete flooding, the diver
may clear the helmet quickly by tilting the helmet
forward and slightly down and activating the defogger
control knob. Pressing in on the manual purge but-
ton in the center of the regulator cover will dewater
the regulator.
After clearing, cautiously check for additional flood-
ing. If the helmet continues to take on water, return
to the diving station, swimming with the water dump
valve positioned at the lowest part of the hat: that is
with the diver’s face forward and slightly tilted down.
Keep the free flow knob on. This increases the air/gas
pressure slightly inside the hat and keeps the water
out. Any incoming water is automatically purged.
3.11.2 Inhalation Resistance
If breathing becomes difficult, adjust the demand
regulator adjustment knob, for easier breathing by
rotating the adjustment knob counter clockwise. If
the breathing does not get noticeably better, press the
purge button in the regulator cover. If a surge of gas
does not flow with this action, open the emergency
valve.
If the flow is noticeably better, immediately notify
topside that you are on emergency gas. Insure your
umbilical is clear and return to the stage or decent line.
The diver should stay in communication with topside
personnel and make preparations to abort the dive.
The console operator should check to ensure the sup-
ply pressure to the diver is at the proper pressure.
3.11.3 Gas Flow Stops
A stop of flow in the demand regulator usually in-
dicates the main gas supply has stopped. The diver
should first open the emergency valve by turning
the knob. If there is still no flow from the demand
regulator, the defogger valve knob should be opened.
Keep in mind that if the defogger valve is left open,
the bailout bottle will drain very quickly, particularly
if the diver is deep.
Immediately notify topside, check to insure your
umbilical is clear and return to the diving station us-
ing the emergency breathing supply. Avoid making a
rapid ascent if at all possible.
Once at the surface, or inside the bell, the diver may
remove the helmet if needed. Never ditch the hel-
met underwater unless conditions absolutely require
that.