Ventilation systems comprised of air impellers, exhaust fans and ventilation hoods; air filtration and air-conditioning installations; ventilation hoods; air flow regulators for air-conditioning, heating and ventilation, namely, dampers as control devices used in air ducts to regulate the flow of air; window ventilators; hygroregulated ventilators; ventilating louvers; exhauster ventilators; ventilation system elements, namely, air impellers, energy recovery ventilators, and ventilating exhaust fans; ventilation apparatus, namely, cordless floor drying cone dolly; ventilators for heat recovery; air-conditioners; air-conditioning system elements, namely, evaporative ail coolers; air-conditioning units; waste heat recovery ventilators; heating machines, namely, heating installations; radiators; air-purification installations, systems, devices and apparatus, namely, air purifiers, and air purifying apparatus and machines