MSA
Pressure Demand Exhalation Valves
part numbers 461613 and 461860
Refer to the illustrated parts list for the apparatus
CLEANING INSTRUCTIONS
General:
Moisture in the breath, saliva, dust collected in the mask,
and perspiration adhering to the valve create a bonding effect
on the valve, which may cause it to stick on the first exhaled
breath. Two styles of valves exist which require different
attention to this problem (See Figures 1A and 1B for pictorial
differences).
Style A in Figure 1A can be manually opened should it
stick during storage. Press on the center pin until it is flush
with the guide hole. The following procedures are
recommended for cleaning. A leaking valve probably only
needs cleaned.
After Each Use:
After washing and rinsing the facepiece, the valve in Style
A must be held open (See Figure 1A) and flushed with rinse
water. Style B does not have this feature. Before the
facepiece is stored, the valve must be forced air dried as
described in Step #8. The purpose of this procedure is to
insure the valve is stored in a dry condition.
Periodic Cleaning:
1. Remove the valve from the Ultravue' facepiece by
unscrewing the nut, Part Number 461610, inside the facepiece
with the special wrench supplied with the apparatus. Remove
the valve from the Clearvue® facepiece by removing the
clamp, Part Number 57909.
CAUTION: When performing the next step
do not stretch or deform the spring which
is inside the valve. Handle the seat
spring
and
valve
stem
assembly
carefully. DO NOT scratch or nick the
valve seats.
2. Disassemble the valve by removing the four screws shown
in figures 1B and 2 with the proper size screwdriver.
over ä
Figure 1A - Manual Opening
Figure 1B - Removing Screws
Figure 2A - Disassembled Valve
