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Description
2.1
Operating Principles
The PremAire Cadet Escape Respirator is a combination supplied-air respirator with self-contained
breathing apparatus (SCBA) for escape.
The PremAire Cadet Escape Respirator utilizes a pressure-demand regulator mounted at the face-
piece. This mask mounted regulator (MMR) maintains a slight positive pressure within the facepiece
while regulating and reducing the air supply to a breathable pressure. This is accomplished by using
a diaphragm that senses the breathing demands of the user in a controlled feedback state. The posi-
tive pressure of air inside the facepiece, whether the wearer is inhaling or exhaling, is to prevent
contaminants from entering the facepiece, should there be slight face-to-facepiece seal leakage.
The respirator is suitable for use with a large, compressed air cylinder of breathable air or a bank of
cylinders set up in cascade fashion. Alternatively, the PremAire Cadet Escape Respirator can be used
with a compressor system designed and configured to supply respirable breathing air to the respirator,
within the NIOSH approved pressure range.
In normal use, the PremAire Cadet Escape Respirator is connected to an air supply of a type and
duration selected by the user and will provide respiratory protection as long as the user remains
connected to the air supply. The respirator allows the wearer to work within the limits of the approved
air-supply hose. The escape cylinder is not to be used for entry. The escape cylinder should not be
used to switch from one airline to another. However, should the primary air supply fail or be inter-
rupted, the emergency escape cylinder enables the wearer to egress from the potentially IDLH atmos-
phere.
2.2
Cylinder and Valve Assembly
The cylinder and valve assembly consists of a cylinder and a combination cylinder valve and first
stage regulator valve. The cylinders are available in 5, 10, and 15 minute rated service time durations.
The cylinders are available in aluminum or carbon fiber material options.
The valve assembly includes a handwheel to open and close the cylinder air supply, a recessed/
protected pressure gauge to measure cylinder contents, a cylinder fill port with check valve to pres-
surize the cylinder, a high pressure relief device to protect the cylinder from over-pressurization, an
intermediate pressure relief valve to protect the second stage regulator from over-pressurization, and
a first stage regulator valve to reduce cylinder pressure to a suitable intermediate pressure. The first
stage regulator valve incorporates a downstream design and dual springs to provide maximum relia-
bility.
2.3
Attachment Hose
The attachment hose is used to connect the air supply hoses to the cylinder and valve assembly. The
attachment hose includes a large sintered filter to remove particulate from the supplied air source. The
attachment hose includes a check valve to prevent loss of air through the hose when the cylinder valve
is open (SCBA mode). MSA approved quick-disconnects are fitted to the end of the attachment hose.
2.4
Second Stage Regulator
The second stage regulator is a pressure-demand regulator. The release button on top of the regu-
lator stops air flow. To stop airflow, push the button in. To restart the regulator, inhale sharply. The
regulator attaches to the facepiece with Push-To-Connect connectors.
PremAire Cadet Escape G1
Description
US
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