Threshold limit value  From Wikipedia, the free encyclopedia
Jump to: navigation, search  The threshold limit value (TLV) of
a chemical substance is a level to which it is believed a worker
can be exposed day after day for a working lifetime without
adverse health effects. Strictly speaking, TLV is a reserved
term of the American Conference of Governmental Industrial
Hygienists (ACGIH). However, it is sometimes loosely used to
refer to other similar concepts used in occupational health and
toxicology. TLVs, along with biological exposure indices (BEIs),
are published annually by the ACGIH.  The TLV is an estimate
based on the known toxicity in humans or animals of a given
chemical substance, and the reliability and accuracy of the
latest sampling and analytical methods. It is not a static
definition since new research can often modify the risk
assessment of substances and new laboratory or instrumental
analysis methods can improve analytical detection limits. The
TLV is a recommendation by ACGIH, with only a