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Immediately Dangerous To Life or Health (IDLH) Values										Related Pages
										Table of IDLH Values
Since the development of the original IDLH values in the 1970s and their subsequent revision in 1994 (NIOSH Documentation for Immediately Dangerous to Life or Health Concentrations (IDLH) (1994))pdf iconpdf icon.  NIOSH has continued to review relevant scientific data and conduct research on methods for develop­ing IDLH values. This has led to the development of Current Intelligence Bulletin (CIB) 66: Derivation of Immediately Dangerous to Life or Health (IDLH) [NIOSH 2014-100].
It is the goal of NIOSH to re-evaluate all IDLH values included in the list below using the guidelines and criteria included in CIB 66. Until this occurs, this list contains IDLH values based on both the 1994 revised criteria and CIB 66 [NIOSH 2014-100]. It is important to note which criteria was applied to develop a specific IDLH value. When a chemical entry contains more than one IDLH value, the IDLH value based on CIB 66 should be treated as current NIOSH policy.
IDLH Values
Substance
CAS no.
IDLH Value (1994)*
New/Updated Values
(2016-present)****Acetaldehyde**
75-07-0
2,000 ppm**Acetic acid**
64-19-7
50 ppm**Acetic anhydride**
108-24-7
200 ppm**Acetone**
67-64-1
2,500 ppm**Acetonitrile**
75-05-8
500 ppm
137 ppm (NIOSH Pub. No. 2017-203)**Acetylene tetrabromide**
79-27-6
8 ppm**Acrolein**
107-02-8
2 ppm**Acrylamide**
79-06-1
60 mg/m3
******Acrylonitrile**
107-13-1
85 ppm
60 ppm (NIOSH Pub. No. 2016-167)**Aldrin**
309-00-2
25 mg/m3
******Allyl alcohol**
107-18-6
20 ppm
******Allyl chloride**
107-05-1
250 ppm
******Allyl glycidyl ether**
106-92-3
50 ppm
******2 Aminopyridine**
504-29-0
5 ppm
******Ammonia**
7664-41-7
300 ppm
******Ammonium sulfamate**
7773-06-0
1,500 mg/m3
******n-Amyl acetate**
628-63-7
1,000 ppm
******sec-Amyl acetate**
626-38-0
1,000 ppm
******Aniline**
62-53-3
100 ppm
******o-Anisidine**
90-04-0
50 mg/m3
******p-Anisidine**
104-94-9
50 mg/m3
******Antimony compounds (as Sb)**
7440-36-0
50 mg Sb/m3
******ANTU**
86-88-4
100 mg/m3
******Arsenic (inorganic compounds, as As)**
7440-38-2 (metal)
5 mg As/m3
******Arsine**
7784-42-1
3 ppm
******Azinphosmethyl**
86-50-0
10 mg/m3
******Barium (soluble compounds, as Ba)**
7440-39-3
50 mg Ba/m3
******Benzene**
71-43-2
500 ppm
******Benzonitrile**


14 ppm (66 mg/m3) (NIOSH Pub. No. 2017-104)**Benzoyl peroxide**
94-36-0
1,500 mg/m3
******Benzyl chloride**
100-44-7
10 ppm
******Beryllium compounds (as Be)**
7440-41-7 (metal)
4 mg Be/m3
******Boron oxide**
1303-86-2
2,000 mg/m3
******Boron trifluoride**
7637-07-2
25 ppm
******Bromine**
7726-95-6
3 ppm
******Bromine Pentafluoride**


1.7 ppm (NIOSH Pub. No. 2017-106)**Bromine trifluoride**
7787-71-5

12 ppm (67 mg/m3) (NIOSH Pub. No. 2020-123)**Bromoform**
75-25-2
850 ppm**Butane**
106-97-8

1,600 ppm (>10% LEL) (NIOSH Pub. No. 2016-174)**1,3-Butadiene**
106-99-0
2,000 ppm
2,000 ppm (10% LEL) (NIOSH Pub. No. 2017-107)**2-Butanone**
78-93-3
3,000 ppm**2-Butoxyethanol**
111-76-2
700 ppm**n-Butyl acetate**
123-86-4
1,700 ppm**sec-Butyl acetate**
105-46-4
1,700 ppm**tert-Butyl acetate**
540-88-5
1,500 ppm**n-Butyl alcohol**
71-36-3
1,400 ppm**sec-Butyl alcohol**
78-92-2
2,000 ppm**tert-Butyl alcohol**
75-65-0
1,600 ppm**n-Butylamine**
109-73-9
300 ppm**tert-Butyl chromate**
1189-85-1
15 mg Cr(VI)/m3**n-Butyl Acrylate**
141-32-2

113 ppm (NIOSH Pub. No. 2016-173)**n-Butyl glycidyl ether**
2426-08-6
250 ppm**n-Butyl mercaptan**
109-79-5
500 ppm**p-tert-Butyltoluene**
98-51-1
100 ppm
******Cadmium dust (as Cd)**
7440-43-9 (metal)
9 mg Cd/m3
******Cadmium fume (as Cd)**
1306-19-0 (CdO)
9 mg Cd/m3[Unc h]
******Calcium arsenate (as As)**
7778-44-1
5 mg As/m3
******Calcium oxide**
1305-78-8
25 mg/m3
******Camphor (synthetic)**
76-22-2
200 mg/m3
******Carbaryl**
63-25-2
100 mg/m3
******Carbon black**
1333-86-4
1,750 mg/m3
******Carbon dioxide**
124-38-9
40,000 ppm
******Carbon disulfide**
75-15-0
500 ppm
******Carbon monoxide**
630-08-0
1,200 ppm
******Carbon tetrachloride**
56-23-5
200 ppm
******Chlordane**
57-74-9
100 mg/m3
******Chlorinated camphene**
8001-35-2
200 mg/m3
******Chlorinated diphenyl oxide**
n/a
5 mg/m3
******Chlorine**
7782-50-5
10 ppm
******Chlorine dioxide**
10049-04-4
5 ppm
******Chlorine Pentafluoride**
13637-63-3

1.7 ppm (NIOSH Pub. No. 2016-170)**Chlorine Trifluoride**
7790-91-2

12 ppm (45 mg/m3) (NIOSH Pub. No. 2020-124)**Chloroacetaldehyde**
107-20-0
45 ppm**Chloroacetonitrile**
107-14-2

14 ppm (NIOSH Pub. No. 2017-201)**alpha-Chloroacetophenone**
532-27-4
15 mg/m3**Chlorobenzene**
108-90-7
1,000 ppm**o-Chlorobenzylidene malononitrile**
2698-41-1
2 mg/m3**Chlorobromomethane**
74-97-5
2,000 ppm**Chlorodiphenyl (42% chlorine)**
53469-21-9
5 mg/m3**Chlorodiphenyl (54% chlorine)**
11097-69-1
5 mg/m3**Chloroform**
67-66-3
500 ppm**1-Chloro-1-nitropropane**
600-25-9
100 ppm**Chloroacetyl Chloride**
79-04-9

1.3 ppm (6 mg/m3)(NIOSH Pub. No. 2016-169)**Chloropicrin**
76-06-2
2 ppm**beta-Chloroprene**
126-99-8
300 ppm**Chromic acid and chromates**
1333-82-0 (CrO3)
15 mg Cr(VI)/m3**Chromium (II) compounds [as Cr(II)]**
n/a
250 mg Cr(II)/m3
******Chromium (III) compounds [as Cr(III)]**
n/a
25 mg Cr(III)/m3
******Chromium metal (as Cr)**
7440-47-3
250 mg Cr/m3
******Coal tar pitch volatiles**
65996-93-2
80 mg/m3
******Cobalt metal, dust and fume (as Co)**
7440-48-4
20 mg Co/m3
******Copper (dusts and mists, as Cu)**
7440-50-8
100 mg Cu/m3
******Copper fume (as Cu)**
1317-38-0 (CuO)
100 mg Cu/m3
******Cotton dust (raw)**
n/a
100 mg/m3
******Crag (r) herbicide**
136-78-7
500 mg/m3
******Cresol (o, m, p isomers)**
95-48-7
250 ppm
******Crotonaldehyde**
4170-30-3
50 ppm
******Cumene**
98-82-8
900 ppm [10% LEL]
******Cyanides (as CN)**
n/a
25 mg/m3(as CN)
******Cyclohexane**
110-82-7
1,300 ppm [10% LEL]
******Cyclohexanol**
108-93-0
400 ppm
******Cyclohexanone**
108-94-1
700 ppm
******Cyclohexene**
110-83-8
2,000 ppm
******Cyclopentadiene**
542-92-7
750 ppm
******2,4-D**
94-75-7
100 mg/m3
******DDT**
50-29-3
500 mg/m3
******Decaborane**
17702-41-9
15 mg/m3
******Demeton**
8065-48-3
10 mg/m3
******Diacetone alcohol**
123-42-2
1,800 ppm [10% LEL]
******Diazomethane**
334-88-3
2 ppm
******Diborane**
19287-45-7
15 ppm
******Dibutyl phosphate**
107-66-4
30 ppm
******Dibutyl phthalate**
84-74-2
4,000 mg/m3
******o-Dichlorobenzene**
95-50-1
200 ppm
******p-Dichlorobenzene**
106-46-7
150 ppm
******Dichlorodifluoromethane**
75-71-8
15,000 ppm
******1,3-Dichloro 5,5-dimethylhydantoin**
118-52-5
5 mg/m3
******1,1-Dichloroethane**
75-34-3
3,000 ppm
******1,2-Dichloroethylene**
540-59-0
1,000 ppm
******Dichloroethyl ether**
111-44-4
100 ppm
******Dichloromonofluoromethane**
75-43-4
5,000 ppm
******1,1-Dichloro-1-Fluoroethane (HCFC-141b)**
1717-00-6

1,700 ppm (8,245 mg/m3) (NIOSH Pub. No. 2016-168)**1,1-Dichloro 1-nitroethane**
594-72-9
25 ppm**Dichlorotetrafluoroethane**
76-14-2
15,000 ppm
******Dichlorvos**
62-73-7
100 mg/m3
******Dieldrin**
60-57-1
50 mg/m3
******Diethylamine**
109-89-7
200 ppm
******2-Diethylaminoethanol**
100-37-8
100 ppm
******Difluorodibromomethane**
75-61-6
2,000 ppm
******Diglycidyl ether**
2238-07-5
10 ppm
******Diisobutyl ketone**
108-83-8
500 ppm
******Diisopropylamine**
108-18-9
200 ppm
******Diketene**


7.6 ppm(NIOSH Pub. No. 2017-108)**Dimethyl acetamide**
127-19-5
300 ppm
******Dimethylamine**
124-40-3
500 ppm
******N,N-Dimethylaniline**
121-69-7
100 ppm
******Dimethyl 1,2-dibromo 2,2-dichlorethyl phosphate**
300-76-5
200 mg/m3
******Dimethylformamide**
68-12-2
500 ppm
******1,1-Dimethylhydrazine**
57-14-7
15 ppm
******Dimethylphthalate**
131-11-3
2,000 mg/m3
******Dimethyl sulfate**
77-78-1
7 ppm
******Dinitrobenzene (o, m, p isomers)**
528-29-0
50 mg/m3
******Dinitroocresol**
534-52-1
5 mg/m3
******Dinitrotoluene**
25321-14-6
50 mg/m3
******Di sec-octyl phthalate**
117-81-7
5,000 mg/m3
******Dioxane**
123-91-1
500 ppm
******Diphenyl**
92-52-4
100 mg/m3
******Dipropylene glycol methyl ether**
34590-94-8
600 ppm
******Endrin**
72-20-8
2 mg/m3
******Epichlorohydrin**
106-89-8
75 ppm
******EPN**
2104-64-5
5 mg/m3
******Ethanolamine**
141-43-5
30 ppm
******2-Ethoxyethanol**
110-80-5
500 ppm
******2-Ethoxyethyl acetate**
111-15-9
500 ppm
******Ethyl acetate**
141-78-6
2,000 ppm [10% LEL]
******Ethyl acrylate**
140-88-5
300 ppm
******Ethyl alcohol**
64-17-5
3,300 ppm [10% LEL]
******Ethylamine**
75-04-7
600 ppm
******Ethyl benzene**
100-41-4
800 ppm [10% LEL]
******Ethyl bromide**
74-96-4
2,000 ppm
******Ethyl butyl ketone**
106-35-4
1,000 ppm
******Ethyl chloride**
75-00-3
3,800 ppm [10% LEL]
******Ethylene chlorohydrin**
107-07-3
7 ppm
******Ethylenediamine**
107-15-3
1,000 ppm
******Ethylene Dibromide**
106-93-4

46 ppm (354 mg/m3) (NIOSH Pub. No. 2020-125)**Ethylene dichloride**
107-06-2
50 ppm
******Ethylene glycol dinitrate**
628-96-6
75 mg/m3
******Ethyleneimine**
151-56-4
100 ppm
******Ethylene oxide**
75-21-8
800 ppm
******Ethyl ether**
60-29-7
1,900 ppm [10% LEL]
******Ethyl formate**
109-94-4
1,500 ppm
******Ethyl mercaptan**
75-08-1
500 ppm
******N-Ethylmorpholine**
100-74-3
100 ppm
******Ethyl silicate**
78-10-4
700 ppm
******Ferbam**
14484-64-1
800 mg/m3
******Ferrovanadium dust**
12604-58-9
500 mg/m3
******Fluorides (as F)**
n/a
250 mg F/m3
******Fluorine**
7782-41-4
25 ppm
******Fluorotrichloromethane**
75-69-4
2,000 ppm
******Formaldehyde**
50-00-0
20 ppm
******Formic acid**
64-18-6
30 ppm
******Furan**
110-00-9

13 ppm (35.1 mg/m3) (NIOSH Pub. No. 2016-171)**Furfural**
98-01-1
100 ppm**Furfuryl alcohol**
98-00-0
75 ppm**Glycidol**
556-52-5
150 ppm**Graphite (natural)**
7782-42-5
1,250 mg/m3**Hafnium compounds (as Hf)**
7440-58-6
50 mg Hf/m3**Heptachlor**
76-44-8
35 mg/m3**n-Heptane**
142-82-5
750 ppm**Hexachloroethane**
67-72-1
300 ppm**Hexachloronaphthalene**
1335-87-1
2 mg/m3**Hexafluoroactone**
684-16-2

9 ppm (61 mg/m3) (NIOSH Pub. No. 2016-172)**n-Hexane**
110-54-3
1,100 ppm [10% LEL]
******2-Hexanone**
591-78-6
1,600 ppm
******Hexone**
108-10-1
500 ppm
******sec Hexyl acetate**
108-84-9
500 ppm
******Hydrazine**
302-01-2
50 ppm
******Hydrogen bromide**
10035-10-6
30 ppm
******Hydrogen chloride**
7647-01-0
50 ppm
******Hydrogen cyanide**
74-90-8
50 ppm
******Hydrogen fluoride (as F)**
7664-39-3
30 ppm
******Hydrogen peroxide**
7722-84-1
75 ppm
******Hydrogen selenide (as Se)**
7783-07-5
1 ppm
******Hydrogen sulfide**
7783-06-4
100 ppm
******Hydroquinone**
123-31-9
50 mg/m3
******Iodine**
7553-56-2
2 ppm
******Iron oxide dust and fume (as Fe)**
1309-37-1
2,500 mg Fe/m3
******Iron Pentacarbonyl**
13463-40-6

0.4 ppm (NIOSH Pub. No. 2016-166)**Isoamyl acetate**
123-92-2
1,000 ppm
******Isoamyl alcohol (primary and secondary)**
123-51-3
500 ppm
******Isobutyl acetate**
110-19-0
1,300 ppm [10% LEL]
******Isobutyl alcohol**
78-83-1
1,600 ppm
******Isophorone**
78-59-1
200 ppm
******Isopropyl acetate**
108-21-4
1,800 ppm
******Isopropyl alcohol**
67-63-0
2,000 ppm [10% LEL]
******Isopropylamine**
75-31-0
750 ppm
******Isopropyl ether**
108-20-3
1,400 ppm [10% LEL]
******Isopropyl glycidyl ether**
4016-14-2
400 ppm
******Ketene**
463-51-4
5 ppm
******Lead compounds (as Pb)**
7439-92-1
100 mg Pb/m3
******Lindane**
58-89-9
50 mg/m3
******Lithium hydride**
7580-67-8
0.5 mg/m3
******L.P.G.**
68476-85-7
2,000 ppm [10% LEL]
******Magnesium oxide fume**
1309-48-4
750 mg/m3
******Malathion**
121-75-5
250 mg/m3
******Maleic anhydride**
108-31-6
10 mg/m3
******Manganese compounds (as Mn)**
7439-96-5 (metal)
500 mg Mn/m3
******Mercury compounds [except (organo) alkyls, as Hg]**
7439-97-6 (metal)
10 mg Hg/m3
******Mercury (organo) alkyl compounds(as Hg)**
n/a
2 mg Hg/m3
******Mesityl oxide**
141-79-7
1,400 ppm [10% LEL]
******Methacrylonitrile**
126-98-7

4.0 ppm (NIOSH Pub. No. 2017-204)**Methoxychlor**
72-43-5
5,000 mg/m3
******Methyl acetate**
79-20-9
3,100 ppm [10% LEL]
******Methyl acetylene**
74-99-7
1,700 ppm [10% LEL]
******Methyl acetylenepropadiene mixture**
59355-75-8
3,400 ppm [10% LEL]
******Methyl acrylate**
96-33-3
250 ppm
******Methylal**
109-87-5
2,200 ppm [10% LEL]
******Methyl alcohol**
67-56-1
6,000 ppm
******Methylamine**
74-89-5
100 ppm
******Methyl (namyl) ketone**
110-43-0
800 ppm
******Methyl bromide**
74-83-9
250 ppm
******Methyl Cellosolve (r)**
109-86-4
200 ppm
******Methyl Cellosolve (r) acetate**
110-49-6
200 ppm
******Methyl chloride**
74-87-3
2,000 ppm
******Methyl chloroform**
71-55-6
700 ppm
******Methylcyclohexane**
108-87-2
1,200 ppm [10% LEL]
******Methylcyclohexanol**
25639-42-3
500 ppm
******o-Methylcyclohexanone**
583-60-8
600 ppm
******Methylene bisphenyl isocyanate**
101-68-8
75 mg/m3
******Methylene chloride**
75-09-2
2,300 ppm
******Methyl formate**
107-31-3
4,500 ppm
******5-Methyl 3-heptanone**
541-85-5
100 ppm
******Methyl hydrazine**
60-34-4
20 ppm
******Methyl iodide**
74-88-4
100 ppm
******Methyl isobutyl carbinol**
108-11-2
400 ppm
******Methyl isocyanate**
624-83-9
3 ppm
0.12 ppm (0.28 mg/m3) (NIOSH Pub. No. 2017-105)**Methyl mercaptan**
74-93-1
150 ppm
******Methyl methacrylate**
80-62-6
1,000 ppm
******Methyl styrene**
98-83-9
700 ppm
******Mica**
12001-26-2
1,500 mg/m3
******Molybdenum (insoluble compounds, as Mo)**
n/a
5,000 mg Mo/m3
******Molybdenum (soluble compounds, as Mo)**
n/a
1,000 mg Mo/m3
******Monomethyl aniline**
100-61-8
100 ppm
******Morpholine**
110-91-8
1,400 ppm [10% LEL]
******Naphtha (coal tar)**
8030-30-6
1,000 ppm [10% LEL]
******Naphthalene**
91-20-3
250 ppm
******Nickel carbonyl (as Ni)**
13463-39-3
2 ppm
******Nickel metal and other compounds (as Ni)**
7440-02-0 (Metal)
10 mg Ni/m3
******Nicotine**
54-11-5
5 mg/m3
******Nitric acid**
7697-37-2
25 ppm
******Nitric oxide**
10102-43-9
100 ppm
******p-Nitroaniline**
100-01-6
300 mg/m3
******Nitrobenzene**
98-95-3
200 ppm
******p-Nitrochlorobenzene**
100-00-5
100 mg/m3
******Nitroethane**
79-24-3
1,000 ppm
******Nitrogen dioxide**
10102-44-0
20 ppm
13 ppm (NIOSHPub. No. 2017-202)**Nitrogen trifluoride**
7783-54-2
1,000 ppm
******Nitroglycerine**
55-63-0
75 mg/m3
******Nitromethane**
75-52-5
750 ppm
******1-Nitropropane**
108-03-2
1,000 ppm
******2-Nitropropane**
79-46-9
100 ppm
******Nitrotoluene (o, m, p isomers)**
88-72-2
200 ppm
******Octachloronaphthalene**
2234-13-1
Unknown
******Octane**
111-65-9
1,000 ppm [10% LEL]
******Oil mist (mineral)**
8012-95-1
2,500 mg/m3
******Osmium tetroxide (as Os)**
20816-12-0
1 mg Os/m3
******Oxalic acid**
144-62-7
500 mg/m3
******Oxygen difluoride**
7783-41-7
0.5 ppm
******Ozone**
10028-15-6
5 ppm
******Paraquat**
1910-42-5
1 mg/m3
******Parathion**
56-38-2
10 mg/m3
******Pentaborane**
19624-22-7
1 ppm
******Pentachloronaphthalene**
1321-64-8
Unknown
******Pentachlorophenol**
87-86-5
2.5 mg/m3
******n-Pentane**
109-66-0
1,500 ppm [10% LEL]
******2-Pentanone**
107-87-9
1,500 ppm
******Perchloromethyl mercaptan**
594-42-3
10 ppm
******Perchloryl fluoride**
7616-94-6
100 ppm
******Petroleum distillates (naphtha)**
8002-05-9
1,100 ppm [10% LEL]
******Phenol**
108-95-2
250 ppm
******p-Phenylene diamine**
106-50-3
25 mg/m3
******Phenyl ether (vapor)**
101-84-8
100 ppm
******Phenyl etherbiphenyl mixture (vapor)**
8004-13-5
10 ppm
******Phenyl glycidyl ether**
122-60-1
100 ppm
******Phenylhydrazine**
100-63-0
15 ppm
******Phosdrin**
7786-34-7
4 ppm
******Phosgene**
75-44-5
2 ppm
******Phosphine**
7803-51-2
50 ppm
******Phosphoric acid**
7664-38-2
1,000 mg/m3
******Phosphorus (yellow)**
7723-14-0
5 mg/m3
******Phosphorus pentachloride**
10026-13-8
70 mg/m3
******Phosphorus pentasulfide**
1314-80-3
250 mg/m3
******Phosphorus trichloride**
7719-12-2
25 ppm
******Phthalic anhydride**
85-44-9
60 mg/m3
******Picric acid**
88-89-1
75 mg/m3
******Pindone**
83-26-1
100 mg/m3
******Platinum (soluble salts, as Pt)**
n/a
4 mg Pt/m3
******Portland cement**
65997-15-1
5,000 mg/m3
******Propane**
74-98-6
2,100 ppm [10% LEL]
******n-Propyl acetate**
109-60-4
1,700 ppm
******n-Propyl alcohol**
71-23-8
800 ppm
******Propylene dichloride**
78-87-5
400 ppm
******Propylene imine**
75-55-8
100 ppm
******Propylene oxide**
75-56-9
400 ppm
******n-Propyl nitrate**
627-13-4
500 ppm
******Pyrethrum**
8003-34-7
5,000 mg/m3
******Pyridine**
110-86-1
1,000 ppm
******Quinone**
106-51-4
100 mg/m3
******Rhodium (metal fume and insoluble compounds, as Rh)**
7440-16-6 (metal)
100 mg Rh/m3
******Rhodium (soluble compounds, as Rh)**
n/a
2 mg Rh/m3
******Ronnel**
299-84-3
300 mg/m3
******Rotenone**
83-79-4
2,500 mg/m3
******Selenium compounds (as Se)**
7782-49-2
1 mg Se/m3
******Selenium hexafluoride**
7783-79-1
2 ppm
******Silica, amorphous**
7631-86-9
3,000 mg/m3
******Silica, crystalline (respirable dust)**
14808-60-7

******cristobalite/tridymite**
14808-60-7
25 mg/m3
******quartz/tripoli**
14808-60-7
50 mg/m3
******Silver (metal dust and soluble compounds, as Ag)**
7440-22-4 (metal)
10 mg Ag/m3
******Soapstone**
n/a
3,000 mg/m3
******Sodium fluoroacetate**
62-74-8
2.5 mg/m3
******Sodium hydroxide**
1310-73-2
10 mg/m3
******Stibine**
7803-52-3
5 ppm
******Stoddard solvent**
8052-41-3
20,000 mg/m3
******Strychnine**
57-24-9
3 mg/m3
******Styrene**
100-42-5
700 ppm
******Sulfur dioxide**
7446-09-5
100 ppm
******Sulfuric acid**
7664-93-9
15 mg/m3
******Sulfur monochloride**
10025-67-9
5 ppm
******Sulfur pentafluoride**
5714-22-7
1 ppm
******Sulfuryl fluoride**
2699-79-8
200 ppm
******2,4,5-T**
93-76-5
250 mg/m3
******Talc**
14807-96-6
1,000 mg/m3
******Tantalum (metal and oxide dust, as Ta)**
7440-25-7 (metal)
2,500 mg Ta/m3
******TEDP**
3689-24-5
10 mg/m3
******Tellurium compounds (as Te)**
13494-80-9
25 mg Te/m3
******Tellurium hexafluoride**
7783-80-4
1 ppm
******TEPP**
107-49-3
5 mg/m3
******Terphenyl (o, m, p isomers)**
84-15-1
500 mg/m3
******1,1,1,2-Tetrachloro 2,2-difluoroethane**
76-11-9
2,000 ppm
******1,1,2,2-Tetrachloro 1,2-difluoroethane**
76-12-0
2,000 ppm
******1,1,2,2-Tetrachloroethane**
79-34-5
100 ppm
******Tetrachloroethylene**
127-18-4
150 ppm
******Tetrachloronaphthalene**
1335-88-2
Unknown
******Tetraethyl lead (as Pb)**
78-00-2
40 mg Pb/m3
******Tetrahydrofuran**
109-99-9
2,000 ppm [10% LEL]
******Tetramethyl lead (as Pb)**
75-74-1
40 mg Pb/m3
******Tetramethyl succinonitrile**
3333-52-6
5 ppm
******Tetranitromethane**
509-14-8
4 ppm
******Tetryl**
479-45-8
750 mg/m3
******Thallium (soluble compounds, as Tl)**
n/a
15 mg Tl/m3
******Thiram**
137-26-8
100 mg/m3
******Tin (inorganic compounds, as Sn)**
n/a
100 mg Sn/m3
******Tin (organic compounds, as Sn)**
n/a
25 mg Sn/m3
******Titanium dioxide**
13463-67-7
5,000 mg/m3
******Toluene**
108-88-3
500 ppm
******Toluene 2,4-diisocyanate**
584-84-9
2.5 ppm
******o-Toluidine**
95-53-4
50 ppm
******Tributyl phosphate**
126-73-8
30 ppm
******1,1,2-Trichloroethane**
79-00-5
100 ppm
******Trichloroethylene**
79-01-6
1,000 ppm
******Trichloronaphthalene**
1321-65-9
Unknown
******1,2,3-Trichloropropane**
96-18-4
100 ppm
******1,1,2-Trichloro 1,2,2-trifluoroethane**
76-13-1
2,000 ppm
******Triethylamine**
121-44-8
200 ppm
******Trifluorobromomethane**
75-63-8
40,000 ppm
******2,4,6-Trinitrotoluene**
118-96-7
500 mg/m3
******Triorthocresyl phosphate**
78-30-8
40 mg/m3
******Triphenyl phosphate**
115-86-6
1,000 mg/m3
******Turpentine**
8006-64-2
800 ppm
******Uranium (insoluble compounds, as U)**
7440-61-1 (metal)
10 mg U/m3
******Uranium (soluble compounds, as U)**
n/a
10 mg U/m3
******Vanadium dust**
1314-62-1
35 mg V/m3
******Vanadium fume**
1314-62-1
35 mg V/m3
******Vinyl toluene**
25013-15-4 (inhibited)
400 ppm
******Warfarin**
81-81-2
100 mg/m3
******Xylene (o, m, p isomers)**
95-47-6
900 ppm
******Xylidine**
1300-73-8
50 ppm
******Yttrium compounds (as Y)**
7440-65-5
500 mg Y/m3
******Zinc chloride fume**
7646-85-7
50 mg/m3
******Zinc oxide**
1314-13-2
500 mg/m3
******Zirconium compounds (as Zr)**
7440-67-7 (Metal)
25 mg Zr/m3Show More
Notes
* Values are based on the NIOSH Documentation for Immediately Dangerous to Life or Health Concentrations (IDLHs) (1994)pdf icon [PDF – 10 MB]
**IDLH values based on the 2014 publication Current Intelligence Bulletin (CIB) 66: Derivation of Immediately Dangerous to Life or Health (IDLH)
							
					
						Page last reviewed:  October 8, 2019					Content source: 	National Institute for Occupational Safety and Health NIOSH Publications & Products
Immediately Dangerous To Life or Health (IDLH) Values
Table of IDLH Values
Criteria for Determining IDLH Values
Historical Documentation
Original (SCP) Values
Abbreviations for IDLH Documentation
Abbreviations for Journal Titles Follow NIOSH Facebook
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