Air cleaning units; Air filtering installations; Air purifiers for automobiles; Air purifiers for household purposes; Air purifying apparatus; Air purifying apparatus and machines; Air sterilizers for household purposes; Filters and filtering devices for air and gas conditioning; Gas purification machines; Germicidal lamps for purifying air; Household air cleaners; Ionization apparatus for the treatment of air; Ozone sanitizers for air and water; Vehicle-mounted air purifying apparatus