abstract:In this study, the improved Japanese salt sampler wasadopted for the air-borne salt sampling tests in coastal areas ofnorthern Taiwan. Thirty-five collection stations were set up inthe northern coastal areas to collect air-borne salt data monthlyfrom 2006 to 2009. As the exposure of structures in thenatural environment, the chloride on the concrete surface ofRC structures would be washed away by the precipitation. Therefore, a two-phase collection method was used to get the total air-borne salt “Cair” and the adhesive air-borne salt“Cadh”. The statistic results showed that the percentage ofCadh/Cair has a high correlation with the volume of effectiveprecipitation. Conclusively, the concentration of chloride ionon the concrete surface can be inferred a linear empiricalformula according to the regional climatic characters to indi-cate the total air-borne salt and the adhesive air-borne salt onconcrete surface respectively.