Action Level 06 : A specific concentration of a toxic substance in the air established by OSHA that when reached makes the performance of certain procedures necessary, e.g., monitoring the air, notifying all employees affected
Environmental Health & Safety, Glossary of Common Laboratory Safety and Hygiene Terms, Columbia University in the City of New York, USA 2008. http://ehs.columbia.edu/Glossary.html, (Lab Sfty and Hyg - Amer) {57}