Air cleaning apparatus; Air cleaning filters (parts of air cleaning machines or installations); Air cleaning instruments; Air cleaning machines; Air cleansing apparatus; Air deodorising apparatus; Air filtering apparatus; Air filters for use as dust extractors; Air freshening apparatus; Air freshening instruments; Air purifying apparatus and machines; Apparatus for cleaning air; Apparatus for collecting dust from the air; Apparatus for filtering breathing air; Apparatus for purifying air; Apparatus for use in deodorising air; Electronic air purification apparatus; Filters for cleaning air; Ion generating air purification apparatus (ionisers); Ionisation apparatus for the treatment of air or water; Ionisers for air treatment; Ionization apparatus for the treatment of air or water; Ionization instruments for the treatment of air or water; Dust filters; Linear air diffusers; Perfume diffusers (electric), other than parts of vacuum cleaners; Supply air diffusers