Despatch LCC1-51-3 - Manual (Page 34)

25
Handling
The filter is shipped in the original carton or package that the filter manufacturer uses.
This will give good storage and maximum protection from dirt and moisture.
HEPA filters should be stored and moved in the shipping carton with in the upright
position. Handling should be kept to a minimum. During installation the filter should be
removed from the shipping carton and installed directly into the oven.
If for any reason an unpackaged filter unit must be placed with its face on the floor or
other surface, the surface must be cleared of every object or irregularity, which might
damage the filter pack.
HEPA Filter Validation Testing
This section describes the Despatch position and recommendations for HEPA filter
testing and oven validation procedures. Despatch guarantees that the filters will meet
specified efficiency ratings when the filter is:
•
properly installed
•
run at or below 200° C, at a constant temperature
•
run before burn-in
D.O.P. Testing
In D.O.P. testing aerosol particles of submicron size are used to spot defects or
measure filter efficiency. Degenerative by-products of this test are distributed
throughout the oven chamber upon heat-up. Therefore Despatch does not recommend
D.O.P. filter testing.
Class 100 Testing
Despatch guarantees the environment within the oven to be Class 100. This
classification is based upon measurement of the particulate level within the oven work
chamber.
Class 100 testing may be performed before or after a proper filter burn-in procedure has
been performed. Despatch will guarantee Class 100 conditions measurements based
on two methods of test. The direct method of test employs an extraction-type
particulate analyzer. The indirect method involves particle settling over a specified
period of time onto a clean disk.