TLV-CS Under Study (Tiers)

Chemical Substances and Other Issues Under Study (TLV-CS Committee)

ACGIH® has a procedure that provides the public with an indication of where those chemical substances and physical agents under study fall in the development process. Tier 1 indicates which chemical substances and physical agents may move forward as an NIC or NIE in the upcoming year, based on their status in the development process. Tier 2 consists of those chemical substances and physical agents that will not move forward but will either remain on or be removed from the Under Study list for the next year. For more information, please see the ACGIH® TLV®/BEI® Development Process.

Tier 1 (may move forward with an NIC proposal in 2022)

Chemical Substances

Bensulfide
Benzene
Buprofezin
1,3-Butadiene
Carbon monoxide
Desflurane
Diazinon
Dicamba
Difluorodibromomethane
Dimethenamid-P
Divinylbenzene-Ethylstyrene mixture
Enflurane
Epichlorohydrin
Ethyl ether
2-ethyl hexane-1-ol (2-ethylhexanol)
Fenoxycarb
Furan
Furfural
Furfuryl alcohol
Glycidyl methacrylate (2,3-Epoxypropyl methacrylate)
Glyphosate
Gram negative bacterial endotoxins
Halothane

Imidacloprid
Iodine and Iodides
Malathion
Methylnaphthalene, all isomers
Nitric acid
Nitroglycerin
n-Propyl nitrate
Parathion
Phenothiazine
Phosphorus (white)
Phosphorus (yellow)
Propylene dichloride (1,2-Dichloropropane)
Propylene glycol dinitrate
Sevoflurane
Silicon carbide
Sodium hypochlorite
Sodium silicates
Tetrachlorvinphos
Tolclofos-methyl
Triclopyr
Triethanolamine
Vinyltoluene, all isomers

Tier 2 (will not move forward with an NIC proposal in 2022)

Chemical Substances

Acetyl salicylic acid
Alkyl acrylates
Anisidine
Antimony and compounds, as Sb
Benzidine
Benzoquinone
Bifenazate
Cadmium
Cadmium carbonate
Cadmium hydroxide
Cadmium nitrate
Carbon dioxide
Carbon nanotubes
Chlorodiphenyl, 42%
Chlorodiphenyl, 54%
Chloromethyl methyl ether
Cobalt carbonyl, as Co
Cobalt hydrocarbonyl
Copper
Diacetyl
3,3’-Dichlorobenzidine
Diesel exhaust
Diiodomethyl p-tolyl sulfone
1,2-Dimethoxyethane
Ethyl acrylate
Fluorides
Formic Acid
Germanium tetrahydride
Hafnium and compounds
Hydrogen peroxide
Indium and compounds
Isoprene
4-4’isopropylidene diphenol (BPA)
Lead and inorganic compounds, as Pb

Manganese cyclopentadienyl tricarbonyl
Methyl acrylate
Methyl n-butyl ketone (2-Hexanone)
2-Methylcyclopentadienyl manganese tricarbonyl
Methylene bisphenyl isocyanate
Metribuzin
Molybdenum
1-Naphthylamine
2-Naphthylamine (Beta)
Nickel and inorganic compounds, including Nickel subsulfide, as Ni
Octachloronaphthalene
Pentaborane
m-Phenylenediamine
o-Phenylenediamine
p-Phenylenediamine
Phosphoric acid
Propane sultone
Sodium sulfate
Stoddard solvent
Subtilisins
Talc
Tetraethyl lead
1,2,3,6-Tetrahydrophthalic anhydride
Tetramethyl lead
Tin, organic compounds
Trichloronaphthalene
Trifloxystrobin
Uranium and compounds
Vinylidene chloride
Vinylidene fluoride
Welding fumes

Chemical Substances Removed from Under Study Effective 7-1-2021

Phosphorus (red)
Silicic Acid

Sulfur Trioxide