Replacement Of Visor - SEKUR SFERA Serie Mode D'emploi

8. Tightness test with test equipment
In the event the mask has been disassembled in order to be cleaned or to have some component parts
replaced, a tightness test must be carried out. Before carrying out the tightness test, make a visual check.
Check valves, housing and rubber gasket in particular, in order to make sure they are clean. Defective parts
must be replaced. Mask which failed the tightness test cannot be used.
8.1. Test rig
The test equipment consists of an inflatable dummy head, a mouthpiece connector, a test rig, a plug to seal
the exhalation valve and a plug to seal the threaded connector. The test equipment, allows for a negative or
positive pressure test. LABMATIC or LABTRONIC test equipment can be supplied by D.P.I. s.r.l..
8.2. Testing
Place the mask to be tested onto the inflatable head (wetting the surface with water) and tighten the head
harness. Inflate until the head becomes stable and in good contact around the sealing edge of the mask. If
necessary, adjust better the head harness. Place the sealing plug on the inlet threaded connector of the mask.
(close also the filter connector in the Sfera SP/A ASB).Follow the test equipment instructions as shown in its
instruction manual.
8.3. Leak tightness of mask and exhalation valves
The mask and exhalation valves pass the tightness test when, with the exhalation valve previously damped,
after a 10 mbar (1000 Pa) negative pressure is created inside the mask, the pressure change is not more than
1 mbar (100 Pa) per minute. If the test is positive, remove the mask from the dummy head and dry it if
necessary. The mask can be used only after passing the tightness test.
9. Storage
The masks must be stored in place at a temperature not higher than 50°C, protected from cold and humidity,
the rays of sun, intense heat, corrosive substances which can damage its rubber, shocks, risk of falling down,
dust and dirt. The rubber parts must not be submitted to prolonged tensions and pressures to avoid
distortion. The masks must be stored in their cases or in special cupboards.
10. Specific maintenance instructions and replacement of spare parts
When the mask is disassembled in order to be cleaned and disinfected, it has to be reassembled following
the same procedure of spare parts replacement unless differently indicated. Make sure that all component
parts are correctly assembled, paying attention to not damage all component parts during these operations.

10.1. Replacement of visor

Loosen the two screws on both sides of the frame paying attention not to lose the bolts. Remove the frame
and then the visor from the groove of its seal. Check that the heat protective element of the frame is
undamaged, if necessary, replace it. Unscrew the external grid of the speech module with the disassembling
tool provided and remove the inner mask by disengaging it carefully from the exhalation valve assembly. Pay
careful attention to the o-ring gasket in the speech module housing. Remove the protective grid from the
threaded connector, use the disassembling tool to unscrew the exhalation valve assembly from the outside
of the mask (following the direction indicated by the arrow) and again paying careful attention to the o-ring
gasket. At this point the threaded input connector can be removed by rotating it approximately 45°. Here
again the o-ring gasket must be carefully kept. Before re-assembling, make a visual check and, if necessary,
replace the damaged or worn component parts with original spare parts. Assemble the components in inverse
order and pay careful attention to the three o-ring gaskets. In order to reassemble easily the visor, moisten
the rubber seal of the visor and the frame with water. For a correct positioning make reference to the two
small circles visible on the upper part of the visor. While reassembling the frame keep in mind that the screws
have to placed from the upper part of the frame.
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