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Threshold Limit Values MeSH Descriptor Data 2025


MeSH Heading
Threshold Limit Values
Tree Number(s)
N03.706.615.917
N06.850.460.350.600.807
Unique ID
D020711
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D020711
Scope Note
Standards for limiting worker exposure to airborne contaminants. They are the maximum concentration in air at which it is believed that a particular substance will not produce adverse health effects with repeated daily exposure. It can be a time-weighted average (TLV-TWA), a short-term value (TLV-STEL), or an instantaneous value (TLV-Ceiling). They are expressed either as parts per million (ppm) or milligram per cubic meter (mg/m3).
Entry Term(s)
STEL
Short-Term Exposure Limit
TLV-BLV
TLV-Biological Limit Value
TLV-Ceiling
TLV-STEL
TLV-TWA
TLV-Time Weighted Average
NLM Classification #
WA 450
See Also
Maximum Allowable Concentration
Public MeSH Note
2000; see MAXIMUM PERMISSIBLE EXPOSURE LEVEL 1976-1999; for TLV see MAXIMUM PERMISSIBLE EXPOSURE LEVEL 1976-1999
History Note
2000; use MAXIMUM ALLOWABLE CONCENTRATION 1976-1999; for TLV use MAXIMUM ALLOWABLE CONCENTRATION 1976-1999
Date Established
2000/01/01
Date of Entry
1999/11/09
Revision Date
2008/07/08

No Qualifiers
Threshold Limit Values Preferred
Short-Term Exposure Limit Narrower
TLV-Biological Limit Value Narrower
TLV-Time Weighted Average Narrower
TLV-Ceiling Narrower
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