The elapsed time between initial contact of a hazardous chemical with the outside surface of a protective clothing material and the time at which the chemical can be detected at the inside surface of the material
John R. Cashman, Emergency Response to Chemical and Biological Agents, Glossary, ISBN 1-56670-355-7, Lewis Publishers, CRC Press LLCU, USA 2000. https://books.google.com.kw/books?id=i0lCG8f_6T8C& pg=PA319&lpg=PA319&dq=Fog+%26+Mist+Emergencies+Glo ssary&source=bl&ots=65he7jtVb3&sig=eihli-g4gRSarGm f6usuIOCuksQ&hl=en&sa=X&ei=odQOVZWKDcv3auXvgKgD&ve d=0CDUQ6AEwBA#v=onepage&q=Fog%20%26%20Mist%20Emerg encies%20Glossary&f=false, (Chem&BiolEmr - Amer) {973}