Penetration 7 : Visible physical entry of a chemical in liquid form through an opening such as a seam, zipper, or similar area. Not on a molecular level as with permeation
DuPont (The Miracles of Science), Literature & Technical Information, Industrial Personal Protection Glossary, Wilmington, DE, USA 2010http://www2.dupont.com/Personal_Protection/en_ HK/tech_info/glossary_industrial.html, (IndPP - Amer) {49}