Biomarine BioPak 240R Revolution, Benchman Manual, Page: 8 / 48

BioPak 240R Benchman Manual
A47D257, Revision K
Page 8 of 48
snaps together in a secure fashion without
the need for connection hardware.
2.4 Breathing Loop
The breathing loop consists of the
breathing chamber, breathing hoses,
facemask connector and facemask.
The breathing chamber consists of the
center section, center section lid and
diaphragm. The spring loaded diaphragm
will maintain positive pressure within the
apparatus. All oxygen gas additions will
occur within the breathing chamber as well
as over pressure venting. Carbon dioxide
is removed from exhalation gas by the
carbon dioxide scrubbers located within
the breathing chamber. Excessive
moisture will be retained by the moisture
containment sponges located within the
center section. Inhalation breathing gas
cooling will be achieved as the gas travels
around the two coolant canisters of the
breathing chamber.
2.5 Oxygen Delivery System
Oxygen will be delivered from the oxygen
cylinder to the breathing loop through a
pressure regulator and manifold system in
one of three different methods.
Pressure demand oxygen additions are
provided whenever the diaphragm of the
breathing chamber reaches the upper
level of its travel and depresses the
demand valve plunger. Additions will be
made at 80 liters/minutes whenever the
demand valve plunger is depressed.
Pressure demand additions occur
whenever the wearer consumes more
oxygen than is supplied by the constant
add.
Constant add oxygen additions are
continually added to the breathing loop at
an average rate of 1.8 liters/minute. This
oxygen addition rate is equivalent to the
oxygen consumption rate of a wearer at a
moderate work rate.
Emergency add oxygen additions occur
whenever the wearer depresses and holds
the red emergency bypass button. This
add will provide 80-100 liters/minute of
oxygen flow and is utilized only for
emergency situations.
2.6 Oxygen Cylinder
The oxygen cylinder is a fully wrapped
aluminum carbon fibre composite cylinder
that is secured into the apparatus via
connection to the pressure regulator and a
hold down strap. The cylinder will provide
containment of the oxygen supply at a 207
bar to provide 440 liters of breathable
oxygen to the wearer.
2.7 Alarming System
The alarming system consists of a
pneumatic pressure gauge and an
electronic monitor to provide the wearer
with independent and redundant system
status indications.
The pressure gauge is mounted on the
harness and retained by a snap strap and
magnet. Remaining stores of oxygen will
be indicated on the gauge and a red band
of color will indicate to the wearer when
oxygen stores have reached 25% of
capacity. The pressure gauge is protected
against sudden loss of oxygen stores in
the event of gauge line severing by a
manual disconnect located at the gauge
pass through point of the housing.
The electronic monitor will provide the
wearer of indications of system status as
listed below through the LED located on
the pneumatic pressure gauge and via an
alarm horn located on the monitor
package.