Ключевые слова: aeration, air, airflow, architecture, bathroom, black, building, circulation, close, contour, drawing, duct, element, emblem, exhaust, flow, frame, graphic, grate, grid, grille, hole, icon, illustration, industrial, industry, iron, line, object, outline, pictogram, round, shape, silhouette, simple, square, symbol, system, technology, vent, ventilate, ventilation, ventilator, white, wind, window,