Checking the opening pressure of the exhalation valve
If using the Quaestor test unit, the opening pressure must at least be
4.2 mbar with a constant flow of 10 liters/minute through the facepiece.
If not, replace spring and repeat test. If using test equipment that does
not permit this constant flow rate (e.g. Testor) the minimum opening
pressure must be 4.5 mbar.
After testing
1. Press button and remove adapter.
2. Remove the facepiece from the test head and dry it if necessary.
3. Fit the exhalation valve cover. Ensure that it engages.
4.4
Special maintenance and care
NOTICE
i
i
Required tools are listed in chapter 8 on page 112.
4.4.1
Replacing the visor
1. Facepieces with metal visor frame:
Unscrew screws, hold tight hexagon nuts.
1. Facepieces with plastic visor frame:
Unscrew screws.
2. Pry the visor frame apart at the joints with a screwdriver, and then
pull the top and bottom halves apart.
3. Remove the support plate if necessary (see chapter 4.4.2 on
page 110).
4. Detach the old visor from the rubber frame.
5. Insert the new visor first in the upper and then in the lower half of
the rubber frame.
The midposition markers on the visor must line up with the seam
on the facepiece body.
6. Pull the rubber frame to the right and left over the rim of the visor.
110
7. Moisten the outside of the rubber frame and the inside of the visor
8. Press on the visor frame, top half first, then lower half.
9. Insert the support plate if necessary.
10. Facepieces with metal visor frame:
11. Facepieces with plastic visor frame:
4.4.2
1. Pull the nose cup out of the groove in the threaded ring.
2. Open the clamping ring with a screwdriver.
3. Remove clamping ring and the parts underneath it (slip ring and
4. Pull the equipment connector out of the facepiece body.
5. Fit the new equipment connector with speech diaphragm and
6. Fit the slip ring and new clamping ring.
7. Attach the hook to ensure the tightest possible fit of the clamping
8. Push the support plate between the clamping ring and the slip ring;
9. Compress the nose on the clamping ring with pliers until the
10. Attach the nose cup. Make sure that the edge is positioned in the
(Use Instructions for NIOSH-approved full facepieces)
frame with soapy water.
Screw the screws into the hex nuts and tighten them until the
distance between the clamping pins is 3 to 0.5 mm.
Insert the screws and tighten them until there is no gap remaining
between the upper and the lower visor frame.
Replacing the equipment connector
support plate).
inhalation and exhalation valves and insert the equipment
connector so that the midposition markers of the equipment
connector and facepiece body line up.
ring.
fit it into the lower visor frame and align.
equipment connector is securely fitted in the facepiece body.
groove all around. The midposition markers of the equipment
connector and the nose cup must line up.
Panorama Nova P