Lin Neng-huei, a professor in the Department of Atmospheric Sciences at National Central University and head of the EPA's acid rain measurement project, says that chemistry defines a pH of seven as neutral, and less than seven as acidic.
環保署酸雨監測計畫總主持人、中央大學大氣科學系教授林能暉指出，化學上我們定義液體的酸鹼度以「pH 值 = 7」為中性，小於 7 則屬酸性。