EN 253:2009+A1:2013 地下熱水網用預制隔熱管道系統.聚氨酯熱絕緣和高密度聚乙烯外皮隔熱的供水鋼管組件 包含修改件A1,2013
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