Impingement 1 : As used in air sampling, impingement refers to a process for the collection of particulate matter in which a particle-containing gas is directed against a wetted glass plate and the particles are retained by the liquid
Barbara A. Plog, Patricia J. Quinlan, Jodey B. Schonfeld and Patricia M. Dewey (editors), Fundamentals of industrial hygiene 5th ed., Appendix E - Glossary (Michael Horowitz, MS, CIH - Compiler), National Safety Council, Illinoise, USA 2002. http://www.wbcsd.org/web/projects/cement/tf3/fihAp pendices.pdf, (Env and Occupn Sfty and Hlth - Amer) {680}