UL Class 1 or 2 Filters?
UL Class 1 or 2 Filters?
(OP)
Doing some air handling unit work in a hospital. I am suggesting that the contractor use UL Class 1 filters, which (when clean) do NOT support combustion. Class 2 filters WILL support combustion.
The contractor is of the opinion that once the filter loads up with lint, that it has lost the UL listing; therefore why install a Class 1 filter?
I am of the opinion that even though this may be the case, it would be foolhardy to specify a filter known to support combustion, when the same product is available that will NOT, even though that fire-proofness will only last, say for 3/4 of the filter life.
I cannot find any references in ASHRAE, ASHE, JCAHO, or even VA standards requiring the use of UL Class 1 filters.
Comments?
The contractor is of the opinion that once the filter loads up with lint, that it has lost the UL listing; therefore why install a Class 1 filter?
I am of the opinion that even though this may be the case, it would be foolhardy to specify a filter known to support combustion, when the same product is available that will NOT, even though that fire-proofness will only last, say for 3/4 of the filter life.
I cannot find any references in ASHRAE, ASHE, JCAHO, or even VA standards requiring the use of UL Class 1 filters.
Comments?





RE: UL Class 1 or 2 Filters?
Also assuming this isn't the only building or AHU, I'd suggest using filters that match all their other units for maintenance sake, so they don't have to order a new kind for every project/fit-out etc.