Long Term Exposure Limit 1 : A time weighted average concentration, usually average over 8 hours, which is appropriate for protecting against the effects of long term exposure
Working Party of the Engineering Practice Committee of the Institution of Chemical Engineers, Nomenclature for Hazard and Risk Assessment in the Process Industries, Rugby, UK 1982. http://cn.manganese.org/images/uploads/pdf/NOMENCL ATURE_OFR_HAZARD_AND_RISK_ ASSESSMENT_IN_THE_PROCESS_INDUSTRIES.pdf, (Nomenclature for Haz and Rsk Assess in the Procss Ind - Brit) {998}