Scott AIR-PAK 75i 2.2 Operating & Maintenance Instructions page 32

CYLINDER REPLACEMENT PROCEDURE
Depleted or partially depleted SCBA cylinders must be replaced with full
cylinders as soon as possible. In normal practice, the user removes the
respirator assembly and places it on solid support to change the cylinder.
Cylinder replacement may also be performed while the user is wearing
the respirator assembly with the assistance of a second individual.
Use only cylinders of the correct rated pressure for the respirator.
• Model 2.2 SCBA's must use only cylinder and valve assemblies
marked for 2216 psig service (30 minute rated only)
• Model 4.5 SCBA's must use only cylinder and valve assemblies
marked for 4500 psig service (30 minute, 45 minute, or one hour
rated)
Always inspect the cylinder valve assembly and the threads on the
cylinder valve assembly before connecting the pressure reducer hose
coupling. Never use a cylinder with a damaged cylinder valve assembly
or a cylinder valve assembly with damaged threads.
To replace a depleted or partially depleted cylinder, proceed as follows:
1. Leave the area requiring respiratory protection and be certain that
respiratory protection is no longer required.
2. Doff the facepiece. (See TERMINATION OF USE section of this in-
struction.)
3. Push in and rotate the cylinder valve knob clockwise and completely
close the cylinder valve.
4. Release residual air pressure in the respirator system by opening
the purge valve slightly. When the flow of air from the facepiece has
stopped, fully close the purge valve.
5. Unthread the pressure reducer hose coupling from the cylinder valve
by rotating counterclockwise.
ALL SCOTT AIR-PAK 75i RESPIRATORS DESCRIBED IN THIS IN-
STRUCTION USE A SPRING LOADED CYLINDER LOCKING TAB LO-
CATED AT THE BOTTOM OF THE BACKFRAME. THE LOCKING TAB
ENGAGES A HANGER TAB WHICH IS PART OF THE VALVE ASSEMBLY
ON ALL SCOTT CYLINDER AND VALVE ASSEMBLIES.
6. Disengage the cylinder retention strap by gripping the latch plate as
shown in FIGURE 15 and lifting on the end of the latch.
RETENTION
CYLINDER RETENTION
7. Grasp the cylinder below the retention strap, push the locking tab
below the valve, then lift the cylinder free from the bottom hook and
remove. See FIGURE 16.
P/N 595236-01 Rev. B 10/11
NOTE
STRAP
FIGURE 15
LATCH
PLATE
Page 32 of 44
WARNING
THE USE OF ANY AIR CYLINDER OTHER
THAN A CYLINDER AND VALVE ASSEMBLY
APPROVED FOR USE WITH THE SPECIFIC
SCOTT AIR-PAK 75i RESPIRATOR MODEL
BEING SERVICED MAY RESULT IN LOSS OF
AIR FROM THE CYLINDER OR IMPROPER
OPERATION OF THE RESPIRATOR.
SEE THE COMPLETE NIOSH APPROVAL
LABEL (SCOTT DOCUMENT 89347-01) SUP-
PLIED WITH THESE INSTRUCTIONS FOR
CYLINDER AND VALVE ASSEMBLIES AP-
PROVED FOR USE WITH SPECIFIC SCOTT
AIR-PAK 75i MODELS.
CAUTION
OVERTIGHTENING THE CYLINDER VALVE
MAY CAUSE DAMAGE THAT COULD RESULT
IN LEAKAGE OF AIR FROM THE CYLINDER.
USE NO TOOLS TO CLOSE THE CYLINDER
VALVE.
WARNING
NEVER USE A DAMAGED CYLINDER OR A
CYLINDER WITH A DAMAGED CYLINDER
VALVE ASSEMBLY OR A CYLINDER VALVE
ASSEMBLY WITH DAMAGED THREADS.
L E A K A G E M A Y O C C U R W H I C H C O U L D
CAUSE A LOSS OF BREATHING AIR OR A
SUDDEN RELEASE OF HIGH PRESSURE
AIR RESULTING IN SERIOUS INJURY OR
DEATH.