LCLO 2 : Lethal Concentration Low. Lowest airborne concentration reported to cause death in humans or animals. Acute exposures are <24 hours while chronic exposures are >24 hours
W. A. N Dorland and E. J. Taylor (editors), Glossary of MSDS Terms, Texas A&M University, USA 2001. http://www.bio.tamu.edu/USERS/TONNA/GLOSSARY.HTM, (MSDS - Amer) {631}