Definition 4 of Annex I, part 2 of Regulation (EU)1253/2014 does not explicitly provide specific indications on the reference configuration for an exhaust UVU. Therefore, the reference configuration of such products shall be in line with the general case ("‘reference configuration of an UVU’ means a product configured with a casing and at least one fan with variable speed or multi-speed drive"). The presence (or lack of) and typology of the filter are left to the manufacturer to determine (and consequently declare).
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