Ключевые слова: air, air pollution, analysis, analyzing, breathing, buildinradioactive contamination, chart, check up, checkup, concepts, confusion, construction industry, control, crawl space, danger, dangerous, diagram, doub, doubts, earth, environmental damage, environmental issues, examination, examining, flooring, foundation, g, gas, graph, graphic, home, house, hygiene, illustration, inspection, natural gas, periodic table, poisonous, pollution, problems, quality control, question, question mark, question marks, radiation, radioactivity, radium, radon, radon test, residential building, risk, safe, screening, single line, soil, steam, test results, trends, uncertainties, uncertainty, water pollution,