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

International studies to ascertain the extent of the environmental pro blems 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 variet y of experimental difficulties which can compromise the validity of th e data. Consequently, it is essential that all investigators use measu rement procedures that are consistent and reproducible. This document provides recommendations on all aspects of the analytical process, inc luding collection, handling and analysis of acid rain samples, to assu re the quality and comparability of the resulting pH data.