Ventilation hoods for laboratories; apparatus for ventilating; air filtering installations; ventilation air-conditioning installations and apparatus; ventilation air-conditioning installations for vehicles; ventilating apparatus for vehicles; air sterilizers; germicidal lamps for purifying air; ionization apparatus for the treatment of air; air purifying apparatus and machines; filters for air conditioning; air filters for industrial and household use; air treatment equipment; household air cleaners; air purifiers