Ключевые слова: air, allergens, allergies, caucasian, ceiling, check, cleaning, conditioner, conditioning, construction, dirty, duct, dust, filter, furnace, grille, hands, home, homeowner, house, hvac, indoors, inside, intake, interior, maintenance, male, man, old, opened, out, person, pleated, removing, repair, repairman, residential, room, safety, service, square, support, system, take, technician, unclean, vent, wall, work, worker,