Air cleaning units; Air cleaning units containing an air filter, ultraviolet lights and a photocatalytic filter; Air filtering installations; Air filters for air conditioners in vehicle passenger compartments; Air filters for air conditioning units; Air filters for domestic use; Apparatus for filtering drinking water; Fibrous filtering media for general industrial use in the purification of air and industrial fluids; Filtering units for water filtering; Filters and filtering devices for air and gas conditioning; Filters for air conditioning; HEPA filters for household use; Water filtering units for domestic use; Water filters; Water filtration and purification units and replacement cartridges and filters therefor