台灣地區大氣腐蝕環境分類

Classification of Atmospheric Corrosivity in Taiwan

大氣腐蝕環境的區分依據ISO 9223，可採用試片腐蝕速率量測與環境因子的分類進行。過去各單位研究台灣地區腐蝕環境分類時，均以現場暴露試驗進行，鮮少採用環境因子分類研究；有鑑於現場暴露試驗維護不易，且國內各地區多無十年以上的腐蝕試驗數據，本文將彙集中央氣象局公佈之相對濕度資料、環保署公佈之SO2濃度與過去各單位調查研究之氯離子濃度數據，進行台灣本島大氣腐蝕環境分類。結果顯示，台灣西部以大甲溪為界，大甲溪以北地區多為C4等級，大甲溪以南多為C3，沿海地區則為C5等級。

According to ISO 9223, classification of atmospheric corrosivity can be performed either by corrosion rate measurement or by environmental classification. In the present study, categories of corrosivity of atmosphere in Taiwan are classified based on environmental classification in terms of time of wetness, pollution of airborne salinity and SO2 guided by ISO 9223. It is found that along west part of Taiwan, northward of Daja creek, corrosiveness category is classified as C4 except Taipei city, which is rated as C3 ; while at southward of Daja creek, corrosiveness category is classified as C3. For coastal and seashore areas, corrosiveness category is classified as C5.