Ключевые слова: air conditioner, air duct, air pollution, air pressure, aspirations, building activity, built structure, construction industry, cracked, crawl space, cross section, danger, dangerous, depressurization, domestic life, house, industry, insulation, material, membrane, natural ventilation, permeability, pipe tube, pipeline, poisonous, polyethylene, polythene, protection, radiation, radioactive contamination, radium, radon, radon gas, radon test, risk, soil, tube,