RECOMMENDATIONS FOR THE ELECTROMETRIC DETERMINATION OF THE PH OF ATMOSPHERIC WET DEPOSITION (ACID-RAIN)

International studies to ascertain the extent of the environmental problems associated with the pH of atmospheric wet deposition (acid rain) are ongoing. Unfortunately, the measurement of pH in unbuffered, low ionic strength solutions, such as wet deposition, is prone to a variety of experimental difficulties which can compromise the validity of the data. Consequently, it is essential that all investigators use measurement procedures that are consistent and reproducible. This document provides recommendations on all aspects of the analytical process, including collection, handling and analysis of acid rain samples, to assure the quality and comparability of the resulting pH data.