DIN EN 253-2015 區域供暖管道.直埋式供熱網絡用預隔熱粘結管系統.鋼制給水管、聚氨脂保溫層和聚乙烯外護套的管道組件.德文版本EN 253-2009+A2-2015
District heating pipes - Preinsulated bonded pipe systems for directly buried hot water networks - Pipe assembly of steel service pipe, polyurethane thermal insulation and outer casing of polyethylene; German version EN 253:2009+A2:2015