Definition:
Threshold Limit Value (TLV) refers to the maximum concentration of a substance, such as asbestos fibers, in workplace air that is considered safe for most workers during a standard workday and workweek without adverse health effects.
Phonetic Pronunciation:
(Thresh-hold Lim-it Val-yoo)
Etymological Origin:
The term originates from English, with "threshold" meaning a limit or boundary, "limit" indicating a maximum allowable level, and "value" referring to a numerical measure. It was first introduced by the American Conference of Governmental Industrial Hygienists (ACGIH) in the mid-20th century as a guideline for occupational exposure.
Significance in Asbestos Context:
TLVs are critical in the field of asbestos as they have historically been used to set workplace exposure limits for asbestos fibers. However, these values have been controversial, as early TLVs for asbestos were set at levels now known to be unsafe, leading to widespread occupational exposure and subsequent asbestos-related diseases like mesothelioma and asbestosis. TLVs are often cited in litigation to argue whether employers or manufacturers adhered to safety standards or failed to protect workers.
Synonyms or Related Terms:
Example Sentence:
"The outdated TLV for asbestos exposure in the 1960s failed to protect workers, many of whom later developed mesothelioma."
Common Misconceptions:
