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29 CFR 1910.1000 & NIOSH Compliant

Occupational Chemical Exposure & PPE Engine

Instant Permissible Exposure Limits (PELs), Extended-Shift Brief & Scala adjustments, Hazard Ratios, and NIOSH-mandated respirator classifications.

Indexed Substances
544 Chemicals
Shift Models
8h / 10h / 12h TWA
Skin Hazard Notations
0 Flagged
Compliance Export
1-Click PDF Audit

Substance Directory

Select any chemical to run operational shift calculations and view PPE requirements.

Showing all 544 substances

(meta)

CAS No: 99-65-0
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

(ortho)

CAS No: 528-29-0
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

(para)

CAS No: 100-25-4
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

1,1,1,2-Tetrachloro-2,2-difluoroethane

CAS No: 76-11-9
OSHA PEL
500 ppm
NIOSH REL
500 ppm
IDLH Limit
5000 ppm

1,1,1-Trichloroethane; see Methyl chloroform

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

1,1,2,2-Tetrachloro-1,2-difluoroethane

CAS No: 76-12-0
OSHA PEL
500 ppm
NIOSH REL
500 ppm
IDLH Limit
5000 ppm

1,1,2,2-Tetrachloroethane

CAS No: 79-34-5
OSHA PEL
5 ppm
NIOSH REL
1 ppm
IDLH Limit
50 ppm

1,1,2-Trichloro-1,2,2-trifluoroethane

CAS No: 76-13-1
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

1,1,2-Trichloroethane

CAS No: 79-00-5
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

1,1-Dichloro-1-nitroethane

CAS No: 594-72-9
OSHA PEL
10 ppm
NIOSH REL
2 ppm
IDLH Limit
100 ppm

1,1-Dichloroethane

CAS No: 75-34-3
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

1,1-Dimethylhydrazine

CAS No: 57-14-7
OSHA PEL
0.5 ppm
NIOSH REL
0.06 ppm
IDLH Limit
5 ppm

1,2,3-Trichloropropane

CAS No: 96-18-4
OSHA PEL
50 ppm
NIOSH REL
10 ppm
IDLH Limit
500 ppm

1,2-Diaminoethane; see Ethylenediamine

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

1,2-Dibromo-3-chloropropane (DBCP); see 1910.1044

CAS No: 96-12-8
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

1,2-Dibromoethane; see Ethylene dibromide

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

1,2-Dichloroethane; see Ethylene dichloride

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

1,2-Dichloroethylene

CAS No: 540-59-0
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

1,2-Dichloropropane; see Propylene dichloride

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

1,2-Epoxypropane; see Propylene oxide

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

1,3-Dichloro-5,5-dimethyl hydantoin

CAS No: 118-52-5
OSHA PEL
0.2 mg/m�
NIOSH REL
0.2 ppm
IDLH Limit
2 ppm

1-Chloro-1-nitropropane

CAS No: 600-25-9
OSHA PEL
20 ppm
NIOSH REL
2 ppm
IDLH Limit
200 ppm

1-Chloro-2,3-epoxypropane; See Epichlorohydrin

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

1-Nitropropane

CAS No: 108-03-2
OSHA PEL
25 ppm
NIOSH REL
25 ppm
IDLH Limit
250 ppm

2,3-Epoxy-1-propanol; see Glycidol

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

2,4,5-T (2,4,5-tri-chlorophenoxyacetic acid)

CAS No: 93-76-5
OSHA PEL
10 mg/m�
NIOSH REL
10 ppm
IDLH Limit
100 ppm

2,4,6-Trinitrophenol;see Picric acid

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

2,4,6-Trinitrophenyl-methyl nitramine; see Tetryl

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

2,4,6-Trinitrotoluene (TNT)

CAS No: 118-96-7
OSHA PEL
1.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
15 ppm

2,4-D (Dichlorophen-oxyacetic acid)

CAS No: 94-75-7
OSHA PEL
10 mg/m�
NIOSH REL
10 ppm
IDLH Limit
100 ppm

2,6-Dimethyl-4-heptanone; see Diisobutyl ketone

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

2-Acetylaminofluorene; see 1910.1014

CAS No: 53-96-3
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

2-Aminoethanol; see Ethanolamine

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

2-Aminopyridine

CAS No: 504-29-0
OSHA PEL
0.5 ppm
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

2-Butanone (Methyl ethyl ketone)

CAS No: 78-93-3
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

2-Butoxyethanol

CAS No: 111-76-2
OSHA PEL
50 ppm
NIOSH REL
5 ppm
IDLH Limit
500 ppm

2-Chloro-1,3-butadiene; See beta-Chloroprene

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

2-Chloro-6-(trichloromethyl)pyridine

CAS No: 1929-82-4
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

2-Chloroethanol; See Ethylene chlorohydrin

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

2-Diethylaminoethanol

CAS No: 100-37-8
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

2-Ethoxyethanol (Cellosolve)

CAS No: 110-80-5
OSHA PEL
200 ppm
NIOSH REL
0.5 ppm
IDLH Limit
2000 ppm

2-Ethoxyethyl acetate (Cellosolve acetate)

CAS No: 111-15-9
OSHA PEL
100 ppm
NIOSH REL
0.5 ppm
IDLH Limit
1000 ppm

2-Hexanone (Methyl n-butyl ketone)

CAS No: 591-78-6
OSHA PEL
100 ppm
NIOSH REL
1 ppm
IDLH Limit
1000 ppm

2-Methoxyethanol; (Methyl cellosolve)

CAS No: 109-86-4
OSHA PEL
25 ppm
NIOSH REL
0.1 ppm
IDLH Limit
250 ppm

2-Methoxyethyl acetate (Methyl cellosolve acetate)

CAS No: 110-49-6
OSHA PEL
25 ppm
NIOSH REL
0.1 ppm
IDLH Limit
250 ppm

2-Nitropropane

CAS No: 79-46-9
OSHA PEL
25 ppm
NIOSH REL
25 ppm
IDLH Limit
250 ppm

2-Pentanone (Methylpropyl ketone)

CAS No: 107-87-9
OSHA PEL
200 ppm
NIOSH REL
150 ppm
IDLH Limit
2000 ppm

3,3'-Dichlorobenzidine;see 1910.1007

CAS No: 91-94-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

4,4'-Thiobis (6-tert,Butyl-m-cresol)

CAS No: 96-69-5
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

4-Aminodiphenyl see 1910.1011

CAS No: 92-67-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

4-Dimethylaminoazo-benzene; see 1910.1015

CAS No: 60-11-7
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

4-Nitrodiphenyl; see 1910.1003

CAS No: 92-93-3
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

ANTU (alpha Naphthylthiourea)

CAS No: 86-88-4
OSHA PEL
0.3 mg/m�
NIOSH REL
0.3 ppm
IDLH Limit
3 ppm

Acetaldehyde

CAS No: 75-07-0
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

Acetic acid

CAS No: 64-19-7
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Acetic anhydride

CAS No: 108-24-7
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Acetone

CAS No: 67-64-1
OSHA PEL
1000 ppm
NIOSH REL
250 ppm
IDLH Limit
10000 ppm

Acetonitrile

CAS No: 75-05-8
OSHA PEL
40 ppm
NIOSH REL
20 ppm
IDLH Limit
400 ppm

Acetylene dichloride; see 1,2-Dichloroethylene

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Acetylene tetrabromide

CAS No: 79-27-6
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Acrolein

CAS No: 107-02-8
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Acrylamide

CAS No: 79-06-1
OSHA PEL
0.3 mg/m�
NIOSH REL
0.03 ppm
IDLH Limit
3 ppm

Acrylonitrile; see 1910.1045

CAS No: 107-13-1
OSHA PEL
Special
NIOSH REL
1 ppm
IDLH Limit
N/A

Aldrin

CAS No: 309-00-2
OSHA PEL
0.25 mg/m�
NIOSH REL
0.25 ppm
IDLH Limit
2.5 ppm

Allyl alcohol

CAS No: 107-18-6
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Allyl chloride

CAS No: 107-05-1
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Allyl glycidyl ether (AGE)

CAS No: 106-92-3
OSHA PEL
10 ppm
NIOSH REL
5 ppm
IDLH Limit
100 ppm

Allyl propyl disulfide

CAS No: 2179-59-1
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Aluminum Metal (as Al)

CAS No: 7429-90-5
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Ammonia

CAS No: 7664-41-7
OSHA PEL
50 ppm
NIOSH REL
25 ppm
IDLH Limit
500 ppm

Ammonium sulfamate

CAS No: 7773-06-0
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Aniline and homologs

CAS No: 62-53-3
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Anisidine (o-,p-isomers)

CAS No: 29191-52-4
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Antimony and compounds (as Sb)

CAS No: 7440-36-0
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Arsenic, inorganic compounds (as As) see 1910.1018

CAS No: 7440-38-2
OSHA PEL
Special
NIOSH REL
0.002 ppm
IDLH Limit
N/A

Arsenic, organic compounds (as As)

CAS No: 7440-38-2
OSHA PEL
0.5 mg/m�
NIOSH REL
See Data
IDLH Limit
5 ppm

Arsine

CAS No: 7784-42-1
OSHA PEL
0.05 ppm
NIOSH REL
0.002 ppm
IDLH Limit
0.5 ppm

Asbestos; see 1910.1001

CAS No: Varies with compound
OSHA PEL
Special
NIOSH REL
0.1 ppm
IDLH Limit
N/A

Azinphos-methyl

CAS No: 86-50-0
OSHA PEL
0.2 mg/m�
NIOSH REL
0.2 ppm
IDLH Limit
2 ppm

Barium sulfate

CAS No: 7727-43-7
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Barium, soluble compounds (as Ba)

CAS No: 7440-39-3
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Benomyl

CAS No: 17804-35-2
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Benzene(f)(Z37.40-1969)

CAS No: 10 ppm
OSHA PEL
25 ppm
NIOSH REL
1 ppm
IDLH Limit
250 ppm

Benzidine; See 1910.1010

CAS No: 92-87-5
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Benzo(a)pyrene; see Coal tar pitch volatiles

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Benzoyl peroxide

CAS No: 94-36-0
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Benzyl chloride

CAS No: 100-44-7
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Beryllium and beryllium compounds (as Be); see1910.1024(n)

CAS No: 7440-41-7
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Beryllium and beryllium compounds(i)(Z37.29-1970)

CAS No: 2 µg/m3
OSHA PEL
5 ppm
NIOSH REL
0.2 ppm
IDLH Limit
50 ppm

Biphenyl; see Diphenyl

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Bismuth telluride, Undoped

CAS No: 1304-82-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Boron oxide

CAS No: 1303-86-2
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Boron trifluoride

CAS No: 7637-07-2
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Bromine

CAS No: 7726-95-6
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Bromoform

CAS No: 75-25-2
OSHA PEL
0.5 ppm
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Butadiene (1,3-Butadiene); See 29 CFR 1910.1051; 29 CFR 1910.19

CAS No: 106-99-0
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Butanethiol; see Butyl mercaptan

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Butyl mercaptan

CAS No: 109-79-5
OSHA PEL
10 ppm
NIOSH REL
0.5 ppm
IDLH Limit
100 ppm

Butylamine

CAS No: 109-73-9
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Cadmium (as Cd); see 1910.1027

CAS No: 7440-43-9
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Cadmium dust(g)(Z37.5-1970)

CAS No: 0.2 mg/m3
OSHA PEL
0.6 ppm
NIOSH REL
1 ppm
IDLH Limit
6 ppm

Cadmium fume(g)(Z37.5-1970)

CAS No: 0.1 mg/m3
OSHA PEL
0.3 ppm
NIOSH REL
1 ppm
IDLH Limit
3 ppm

Calcium Carbonate

CAS No: 1317-65-3
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Calcium hydroxide

CAS No: 1305-62-0
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Calcium oxide

CAS No: 1305-78-8
OSHA PEL
5 mg/m�
NIOSH REL
2 ppm
IDLH Limit
50 ppm

Calcium silicate

CAS No: 1344-95-2
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Calcium sulfate

CAS No: 7778-18-9
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Camphor, synthetic

CAS No: 76-22-2
OSHA PEL
2 mg/m�
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Carbaryl (Sevin)

CAS No: 63-25-2
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Carbon black

CAS No: 1333-86-4
OSHA PEL
3.5 mg/m�
NIOSH REL
3.5 ppm
IDLH Limit
35 ppm

Carbon dioxide

CAS No: 124-38-9
OSHA PEL
5000 ppm
NIOSH REL
5000 ppm
IDLH Limit
50000 ppm

Carbon disulfide

CAS No: 75-15-0
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Carbon disulfide (Z37.3-1968)

CAS No: 20 ppm
OSHA PEL
30 ppm
NIOSH REL
1 ppm
IDLH Limit
300 ppm

Carbon monoxide

CAS No: 630-08-0
OSHA PEL
50 ppm
NIOSH REL
35 ppm
IDLH Limit
500 ppm

Carbon tetrachloride

CAS No: 56-23-5
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Carbon tetrachloride (Z37.17-1967)

CAS No: 10 ppm
OSHA PEL
25 ppm
NIOSH REL
2 ppm
IDLH Limit
250 ppm

Cellulose

CAS No: 9004-34-6
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Chlordane

CAS No: 57-74-9
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Chlorinated camphene

CAS No: 8001-35-2
OSHA PEL
0.5 mg/m�
NIOSH REL
See Data
IDLH Limit
5 ppm

Chlorinated diphenyl oxide

CAS No: 55720-99-5
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Chlorine

CAS No: 7782-50-5
OSHA PEL
1 ppm
NIOSH REL
0.5 ppm
IDLH Limit
10 ppm

Chlorine dioxide

CAS No: 10049-04-4
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Chlorine trifluoride

CAS No: 7790-91-2
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Chloroacetaldehyde

CAS No: 107-20-0
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Chlorobenzene

CAS No: 108-90-7
OSHA PEL
75 ppm
NIOSH REL
75 ppm
IDLH Limit
750 ppm

Chlorobromomethane

CAS No: 74-97-5
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

Chlorodiphenyl (42% Chlorine) (PCB)

CAS No: 53469-21-9
OSHA PEL
1 mg/m�
NIOSH REL
0.001 ppm
IDLH Limit
10 ppm

Chlorodiphenyl (54% Chlorine) (PCB)

CAS No: 11097-69-1
OSHA PEL
0.5 mg/m�
NIOSH REL
0.001 ppm
IDLH Limit
5 ppm

Chloroethylene; see Vinyl chloride

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Chloroform (Trichloromethane)

CAS No: 67-66-3
OSHA PEL
50 ppm
NIOSH REL
2 ppm
IDLH Limit
500 ppm

Chloromethyl methyl ethersee 1910.1006

CAS No: 107-30-2
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Chloropicrin

CAS No: 76-06-2
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Chromic acid and chromates(h)(Z37-7-1971)

CAS No: N/A
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Chromium (II) compounds (as Cr)

CAS No: 7440-47-3
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Chromium (III) compounds (as Cr)

CAS No: 7440-47-3
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Chromium (VI) compounds See 1910.1026(k)

CAS No: N/A
OSHA PEL
Special
NIOSH REL
0.0002 ppm
IDLH Limit
N/A

Chromium metal and insol. salts (as Cr)

CAS No: 7440-47-3
OSHA PEL
1 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
10 ppm

Chrysene; see Coal tarpitch volatiles

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Clopidol

CAS No: 2971-90-6
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Coal dust (greater than or equal to 5% SiO2respirable fraction)

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Coal dust (less than 5% SiO2, respirable fraction)

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Coal tar pitch volatiles (benzene soluble fraction), anthracene, BaP, phenanthrene, acridine, chrysene, pyrene)

CAS No: 65966-93-2
OSHA PEL
0.2 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
2 ppm

Cobalt metal, dust, and fume (as Co)

CAS No: 7440-48-4
OSHA PEL
0.1 mg/m�
NIOSH REL
0.05 ppm
IDLH Limit
1 ppm

Coke oven emissions; see 1910.1029

CAS No: N/A
OSHA PEL
Special
NIOSH REL
0.2 ppm
IDLH Limit
N/A

Copper

CAS No: 7440-50-8
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Cotton dust(l), see 1910.1043

CAS No: N/A
OSHA PEL
1 mg/m�
NIOSH REL
0.2 ppm
IDLH Limit
10 ppm

Crag herbicide (Sesone)

CAS No: 136-78-7
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Cresol, all isomers

CAS No: 1319-77-3
OSHA PEL
5 ppm
NIOSH REL
2.3 ppm
IDLH Limit
50 ppm

Cristobalite; see 1910.1053(m)

CAS No: 14464-46-1
OSHA PEL
Special
NIOSH REL
0.05 ppm
IDLH Limit
N/A

Crotonaldehyde

CAS No: 123-73-9 /4170-30-3
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Cumene

CAS No: 98-82-8
OSHA PEL
50 ppm
NIOSH REL
50 ppm
IDLH Limit
500 ppm

Cyanides (as CN)

CAS No: Varies with compound
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Cyclohexane

CAS No: 110-82-7
OSHA PEL
300 ppm
NIOSH REL
300 ppm
IDLH Limit
3000 ppm

Cyclohexanol

CAS No: 108-93-0
OSHA PEL
50 ppm
NIOSH REL
50 ppm
IDLH Limit
500 ppm

Cyclohexanone

CAS No: 108-94-1
OSHA PEL
50 ppm
NIOSH REL
25 ppm
IDLH Limit
500 ppm

Cyclohexene

CAS No: 110-83-8
OSHA PEL
300 ppm
NIOSH REL
300 ppm
IDLH Limit
3000 ppm

Cyclopentadiene

CAS No: 542-92-7
OSHA PEL
75 ppm
NIOSH REL
75 ppm
IDLH Limit
750 ppm

Decaborane

CAS No: 17702-41-9
OSHA PEL
0.05 ppm
NIOSH REL
0.05 ppm
IDLH Limit
0.5 ppm

Demeton (Systox)

CAS No: 8065-48-3
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Di-sec octyl phthalate (Di-(2-ethylhexyl) phthalate)

CAS No: 117-81-7
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Diacetone alcohol (4-Hydroxy-4-methyl-2-pentanone)

CAS No: 123-42-2
OSHA PEL
50 ppm
NIOSH REL
50 ppm
IDLH Limit
500 ppm

Diazomethane

CAS No: 334-88-3
OSHA PEL
0.2 ppm
NIOSH REL
0.2 ppm
IDLH Limit
2 ppm

Diborane

CAS No: 19287-45-7
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Dibutyl phosphate

CAS No: 107-66-4
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Dibutyl phthalate

CAS No: 84-74-2
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Dichlorodifluoromethane

CAS No: 75-71-8
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Dichlorodiphenyltrichloroethane (DDT)

CAS No: 50-29-3
OSHA PEL
1 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
10 ppm

Dichloroethyl ether

CAS No: 111-44-4
OSHA PEL
15 ppm
NIOSH REL
5 ppm
IDLH Limit
150 ppm

Dichloromethane; see Methylene chloride

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Dichloromonofluoromethane

CAS No: 75-43-4
OSHA PEL
1000 ppm
NIOSH REL
10 ppm
IDLH Limit
10000 ppm

Dichlorotetrafluoroethane

CAS No: 76-14-2
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Dichlorvos (DDVP)

CAS No: 62-73-7
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Dicyclopentadienyl iron

CAS No: 102-54-5
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Dieldrin

CAS No: 60-57-1
OSHA PEL
0.25 mg/m�
NIOSH REL
0.25 ppm
IDLH Limit
2.5 ppm

Diethyl ether; see Ethyl ether

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Diethylamine

CAS No: 109-89-7
OSHA PEL
25 ppm
NIOSH REL
10 ppm
IDLH Limit
250 ppm

Difluorodibromomethane

CAS No: 75-61-6
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Diglycidyl ether (DGE)

CAS No: 2238-07-5
OSHA PEL
0.5 ppm
NIOSH REL
0.1 ppm
IDLH Limit
5 ppm

Dihydroxybenzene; see Hydroquinone

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Diisobutyl ketone

CAS No: 108-83-8
OSHA PEL
50 ppm
NIOSH REL
25 ppm
IDLH Limit
500 ppm

Diisopropylamine

CAS No: 108-18-9
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Dimethoxymethane; see Methylal

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Dimethyl acetamide

CAS No: 127-19-5
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Dimethyl sulfate

CAS No: 77-78-1
OSHA PEL
1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
10 ppm

Dimethyl-1,2-dibromo-2,2-dichloroethylphosphate

CAS No: 300-76-5
OSHA PEL
3 mg/m�
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Dimethylamine

CAS No: 124-40-3
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Dimethylaminobenzene; see Xylidine

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Dimethylaniline (N,N-Dimethylaniline)

CAS No: 121-69-7
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Dimethylbenzene; see Xylene

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Dimethylformamide

CAS No: 68-12-2
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Dimethylphthalate

CAS No: 131-11-3
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Dinitro-o-cresol

CAS No: 534-52-1
OSHA PEL
0.2 mg/m�
NIOSH REL
0.2 ppm
IDLH Limit
2 ppm

Dinitrobenzene (all isomers)

CAS No: N/A
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Dinitrotoluene

CAS No: 25321-14-6
OSHA PEL
1.5 mg/m�
NIOSH REL
1.5 ppm
IDLH Limit
15 ppm

Dioxane (Diethylene dioxide)

CAS No: 123-91-1
OSHA PEL
100 ppm
NIOSH REL
1 ppm
IDLH Limit
1000 ppm

Diphenyl (Biphenyl)

CAS No: 92-52-4
OSHA PEL
0.2 ppm
NIOSH REL
0.2 ppm
IDLH Limit
2 ppm

Diphenylmethane diisocyanate; see Methylene bisphenylisocyanate

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Dipropylene glycol methyl ether

CAS No: 34590-94-8
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Dusts and mists (as Cu)

CAS No: N/A
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

EPN

CAS No: 2104-64-5
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Emery

CAS No: 12415-34-8
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Endrin

CAS No: 72-20-8
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Epichlorohydrin

CAS No: 106-89-8
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Ethanethiol; see Ethyl mercaptan

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Ethanolamine

CAS No: 141-43-5
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Ethyl acetate

CAS No: 141-78-6
OSHA PEL
400 ppm
NIOSH REL
400 ppm
IDLH Limit
4000 ppm

Ethyl acrylate

CAS No: 140-88-5
OSHA PEL
25 ppm
NIOSH REL
25 ppm
IDLH Limit
250 ppm

Ethyl alcohol (Ethanol)

CAS No: 64-17-5
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Ethyl amyl ketone (5-Methyl-3-heptanone)

CAS No: 541-85-5
OSHA PEL
25 ppm
NIOSH REL
25 ppm
IDLH Limit
250 ppm

Ethyl benzene

CAS No: 100-41-4
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Ethyl bromide

CAS No: 74-96-4
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

Ethyl butyl ketone (3-Heptanone)

CAS No: 106-35-4
OSHA PEL
50 ppm
NIOSH REL
50 ppm
IDLH Limit
500 ppm

Ethyl chloride

CAS No: 75-00-3
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Ethyl ether

CAS No: 60-29-7
OSHA PEL
400 ppm
NIOSH REL
400 ppm
IDLH Limit
4000 ppm

Ethyl formate

CAS No: 109-94-4
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Ethyl mercaptan

CAS No: 75-08-1
OSHA PEL
10 ppm
NIOSH REL
0.5 ppm
IDLH Limit
100 ppm

Ethyl silicate

CAS No: 78-10-4
OSHA PEL
100 ppm
NIOSH REL
10 ppm
IDLH Limit
1000 ppm

Ethylamine

CAS No: 75-04-7
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Ethylene chlorohydrin

CAS No: 107-07-3
OSHA PEL
5 ppm
NIOSH REL
1 ppm
IDLH Limit
50 ppm

Ethylene dibromide

CAS No: 106-93-4
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Ethylene dibromide (Z37.31-1970)

CAS No: 20 ppm
OSHA PEL
30 ppm
NIOSH REL
0.13 ppm
IDLH Limit
300 ppm

Ethylene dichloride (1,2-Dichloroethane)

CAS No: 107-06-2
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Ethylene dichloride (Z37.21-1969)

CAS No: 50 ppm
OSHA PEL
100 ppm
NIOSH REL
1 ppm
IDLH Limit
1000 ppm

Ethylene glycol dinitrate

CAS No: 628-96-6
OSHA PEL
0.2 ppm
NIOSH REL
0.1 ppm
IDLH Limit
2 ppm

Ethylene glycol methylacetate; see Methylcellosolve acetate

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Ethylene oxide; see 1910.1047

CAS No: 75-21-8
OSHA PEL
Special
NIOSH REL
0.1 ppm
IDLH Limit
N/A

Ethylenediamine

CAS No: 107-15-3
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Ethyleneimine; see 1910.1012

CAS No: 151-56-4
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Ethylidene chloride; see 1,1-Dichlorethane

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Ferbam

CAS No: 14484-64-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Ferrovanadium dust

CAS No: 12604-58-9
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Fluoride as dust (Z37.28-1969)

CAS No: 2.5 mg/m3
OSHA PEL
Special
NIOSH REL
2.5 ppm
IDLH Limit
N/A

Fluorides (as F)

CAS No: Varies with compound
OSHA PEL
2.5 mg/m�
NIOSH REL
2.5 ppm
IDLH Limit
25 ppm

Fluorine

CAS No: 7782-41-4
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Fluorotrichloromethane (Trichlorofluoromethane)

CAS No: 75-69-4
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Formaldehyde; see 1910.1048

CAS No: 50-00-0
OSHA PEL
Special
NIOSH REL
0.016 ppm
IDLH Limit
N/A

FormaldehydeSee 1910.1048

CAS No: N/A
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Formic acid

CAS No: 64-18-6
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Fume (as Cu)

CAS No: N/A
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Fume (as V2O5)

CAS No: N/A
OSHA PEL
0.1 mg/m�
NIOSH REL
0.05 ppm
IDLH Limit
1 ppm

Furfural

CAS No: 98-01-1
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Furfuryl alcohol

CAS No: 98-00-0
OSHA PEL
50 ppm
NIOSH REL
10 ppm
IDLH Limit
500 ppm

Glycerin (mist)

CAS No: 56-81-5
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Glycidol

CAS No: 556-52-5
OSHA PEL
50 ppm
NIOSH REL
25 ppm
IDLH Limit
500 ppm

Glycol monoethyl ether; see 2-Ethoxyethanol

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Grain dust (oat, wheat barley)

CAS No: N/A
OSHA PEL
10 mg/m�
NIOSH REL
4 ppm
IDLH Limit
100 ppm

Graphite, natural respirable dust

CAS No: 7782-42-5
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Graphite, synthetic

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Guthion; see Azinphos methyl

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Gypsum

CAS No: 13397-24-5
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Hafnium

CAS No: 7440-58-6
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Heptachlor

CAS No: 76-44-8
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Heptane (n-Heptane)

CAS No: 142-82-5
OSHA PEL
500 ppm
NIOSH REL
85 ppm
IDLH Limit
5000 ppm

Hexachloroethane

CAS No: 67-72-1
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Hexachloronaphthalene

CAS No: 1335-87-1
OSHA PEL
0.2 mg/m�
NIOSH REL
0.2 ppm
IDLH Limit
2 ppm

Hexone (Methyl isobutyl ketone)

CAS No: 108-10-1
OSHA PEL
100 ppm
NIOSH REL
50 ppm
IDLH Limit
1000 ppm

Hydrazine

CAS No: 302-01-2
OSHA PEL
1 ppm
NIOSH REL
0.03 ppm
IDLH Limit
10 ppm

Hydrogen bromide

CAS No: 10035-10-6
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Hydrogen chloride

CAS No: 7647-01-0
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Hydrogen cyanide

CAS No: 74-90-8
OSHA PEL
10 ppm
NIOSH REL
4.7 ppm
IDLH Limit
100 ppm

Hydrogen fluoride (Z37.28-1969)

CAS No: 3 ppm
OSHA PEL
Special
NIOSH REL
0.4 ppm
IDLH Limit
N/A

Hydrogen fluoride (as F)

CAS No: 7664-39-3
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Hydrogen peroxide

CAS No: 7722-84-1
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Hydrogen selenide (as Se)

CAS No: 7783-07-5
OSHA PEL
0.05 ppm
NIOSH REL
0.05 ppm
IDLH Limit
0.5 ppm

Hydrogen sulfide

CAS No: 7783-06-4
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Hydrogen sulfide (Z37.2-1966)

CAS No: N/A
OSHA PEL
20 ppm
NIOSH REL
10 ppm
IDLH Limit
200 ppm

Hydroquinone

CAS No: 123-31-9
OSHA PEL
2 mg/m�
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Insoluble Compounds

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Insoluble Compounds - Total dust

CAS No: N/A
OSHA PEL
15 mg/m�
NIOSH REL
See Data
IDLH Limit
150 ppm

Iodine

CAS No: 7553-56-2
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Iron oxide

CAS No: 1309-37-1
OSHA PEL
10 mg/m�
NIOSH REL
5 ppm
IDLH Limit
100 ppm

Isoamyl acetate

CAS No: 123-92-2
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Isoamyl alcohol (primary and secondary)

CAS No: 123-51-3
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Isobutyl acetate

CAS No: 110-19-0
OSHA PEL
150 ppm
NIOSH REL
150 ppm
IDLH Limit
1500 ppm

Isobutyl alcohol

CAS No: 78-83-1
OSHA PEL
100 ppm
NIOSH REL
50 ppm
IDLH Limit
1000 ppm

Isophorone

CAS No: 78-59-1
OSHA PEL
25 ppm
NIOSH REL
4 ppm
IDLH Limit
250 ppm

Isopropyl acetate

CAS No: 108-21-4
OSHA PEL
250 ppm
NIOSH REL
250 ppm
IDLH Limit
2500 ppm

Isopropyl alcohol

CAS No: 67-63-0
OSHA PEL
400 ppm
NIOSH REL
400 ppm
IDLH Limit
4000 ppm

Isopropyl ether

CAS No: 108-20-3
OSHA PEL
500 ppm
NIOSH REL
500 ppm
IDLH Limit
5000 ppm

Isopropyl glycidyl ether (IGE)

CAS No: 4016-14-2
OSHA PEL
50 ppm
NIOSH REL
50 ppm
IDLH Limit
500 ppm

Isopropylamine

CAS No: 75-31-0
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Kaolin

CAS No: 1332-58-7
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Ketene

CAS No: 463-51-4
OSHA PEL
0.5 ppm
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

L.P.G. (Liquified petroleum gas)

CAS No: 68476-85-7
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Lead inorganic (as Pb);see 1910.1025

CAS No: 7439-92-1
OSHA PEL
Special
NIOSH REL
0.05 ppm
IDLH Limit
N/A

Limestone

CAS No: 1317-65-3
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Lindane

CAS No: 58-89-9
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Lithium hydride

CAS No: 7580-67-8
OSHA PEL
0.025 mg/m�
NIOSH REL
0.025 ppm
IDLH Limit
0.25 ppm

Magnesite

CAS No: 546-93-0
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Magnesium oxide fume - Total Particulate

CAS No: 1309-48-4
OSHA PEL
15 mg/m�
NIOSH REL
See Data
IDLH Limit
150 ppm

Malathion - Total dust

CAS No: 121-75-5
OSHA PEL
15 mg/m�
NIOSH REL
10 ppm
IDLH Limit
150 ppm

Maleic anhydride

CAS No: 108-31-6
OSHA PEL
0.25 ppm
NIOSH REL
1 ppm
IDLH Limit
2.5 ppm

Manganese compounds (as Mn)

CAS No: 7439-96-5
OSHA PEL
5 mg/m�
NIOSH REL
1 ppm
IDLH Limit
50 ppm

Manganese fume (as Mn)

CAS No: 7439-96-5
OSHA PEL
5 mg/m�
NIOSH REL
1 ppm
IDLH Limit
50 ppm

Marble

CAS No: 1317-65-3
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Mercury (Z37.8-1971)

CAS No: N/A
OSHA PEL
0.1 ppm
NIOSH REL
0.025 ppm
IDLH Limit
1 ppm

Mercury (aryl and inorganic) (as Hg)

CAS No: 7439-97-6
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Mercury (organo) alkylcompounds (as Hg)

CAS No: 7439-97-6
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Mercury (vapor) (as Hg)

CAS No: 7439-97-6
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Mesityl oxide

CAS No: 141-79-7
OSHA PEL
25 ppm
NIOSH REL
10 ppm
IDLH Limit
250 ppm

Methanethiol; see Methyl mercaptan

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Methoxychlor - Total dust

CAS No: 72-43-5
OSHA PEL
15 mg/m�
NIOSH REL
See Data
IDLH Limit
150 ppm

Methyl acetate

CAS No: 79-20-9
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

Methyl acetylene (Propyne)

CAS No: 74-99-7
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Methyl acetylene propadiene mixture (MAPP)

CAS No: N/A
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Methyl acrylate

CAS No: 96-33-3
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Methyl alcohol

CAS No: 67-56-1
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

Methyl amyl alcohol; see Methyl Isobutylcarbinol

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Methyl bromide

CAS No: 74-83-9
OSHA PEL
20 ppm
NIOSH REL
20 ppm
IDLH Limit
200 ppm

Methyl butyl ketone; see 2-Hexanone

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Methyl cellosolve acetate; see 2-Methoxyethylacetate

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Methyl cellosolve; see 2-Methoxyethanol

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Methyl chloride

CAS No: 74-87-3
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Methyl chloride (Z37.18-1969)

CAS No: 100 ppm
OSHA PEL
200 ppm
NIOSH REL
50 ppm
IDLH Limit
2000 ppm

Methyl chloroform (1,1,1-Trichloro-ethane)

CAS No: 71-55-6
OSHA PEL
350 ppm
NIOSH REL
350 ppm
IDLH Limit
3500 ppm

Methyl ethyl ketone (MEK); see 2-Butanone

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Methyl formate

CAS No: 107-31-3
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Methyl hydrazine (Monomethylhydrazine)

CAS No: 60-34-4
OSHA PEL
0.2 ppm
NIOSH REL
0.04 ppm
IDLH Limit
2 ppm

Methyl iodide

CAS No: 74-88-4
OSHA PEL
5 ppm
NIOSH REL
2 ppm
IDLH Limit
50 ppm

Methyl isoamyl ketone

CAS No: 110-12-3
OSHA PEL
100 ppm
NIOSH REL
50 ppm
IDLH Limit
1000 ppm

Methyl isobutyl carbinol

CAS No: 108-11-2
OSHA PEL
25 ppm
NIOSH REL
25 ppm
IDLH Limit
250 ppm

Methyl isobutyl ketone; see Hexone

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Methyl isocyanate

CAS No: 624-83-9
OSHA PEL
0.02 ppm
NIOSH REL
0.02 ppm
IDLH Limit
0.2 ppm

Methyl mercaptan

CAS No: 74-93-1
OSHA PEL
10 ppm
NIOSH REL
0.5 ppm
IDLH Limit
100 ppm

Methyl methacrylate

CAS No: 80-62-6
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Methyl n-amyl ketone

CAS No: 110-43-0
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Methyl propyl ketone; see 2-Pentanone

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Methylal (Dimethoxy-methane)

CAS No: 109-87-5
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Methylamine

CAS No: 74-89-5
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Methylcyclohexane

CAS No: 108-87-2
OSHA PEL
500 ppm
NIOSH REL
400 ppm
IDLH Limit
5000 ppm

Methylcyclohexanol

CAS No: 25639-42-3
OSHA PEL
100 ppm
NIOSH REL
50 ppm
IDLH Limit
1000 ppm

Methylene ChlorideSee 1910.1052

CAS No: N/A
OSHA PEL
25 ppm
NIOSH REL
25 ppm
IDLH Limit
250 ppm

Methylene bisphenyl isocyanate (MDI)

CAS No: 101-68-8
OSHA PEL
0.02 ppm
NIOSH REL
0.05 ppm
IDLH Limit
0.2 ppm

Methylene chloride

CAS No: 75-09-2
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Mica (respirable dust)

CAS No: 12001-26-2
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Mica; see Silicates

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Molybdenum (as Mo)

CAS No: 7439-98-7
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Monomethyl aniline

CAS No: 100-61-8
OSHA PEL
2 ppm
NIOSH REL
0.5 ppm
IDLH Limit
20 ppm

Monomethyl hydrazine; see Methyl hydrazine

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Morpholine

CAS No: 110-91-8
OSHA PEL
20 ppm
NIOSH REL
20 ppm
IDLH Limit
200 ppm

N-Ethylmorpholine

CAS No: 100-74-3
OSHA PEL
20 ppm
NIOSH REL
5 ppm
IDLH Limit
200 ppm

N-Nitrosodimethylamine; see 1910.1016

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Naphtha (Coal tar)

CAS No: 8030-30-6
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Naphthalene

CAS No: 91-20-3
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Nickel carbonyl (as Ni)

CAS No: 13463-39-3
OSHA PEL
0.001 ppm
NIOSH REL
0.001 ppm
IDLH Limit
0.01 ppm

Nickel, metal and insoluble compounds (as Ni)

CAS No: 7440-02-0
OSHA PEL
1 mg/m�
NIOSH REL
0.015 ppm
IDLH Limit
10 ppm

Nickel, soluble compounds (as Ni)

CAS No: 7440-02-0
OSHA PEL
1 mg/m�
NIOSH REL
0.015 ppm
IDLH Limit
10 ppm

Nicotine

CAS No: 54-11-5
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Nitric acid

CAS No: 7697-37-2
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Nitric oxide

CAS No: 10102-43-9
OSHA PEL
25 ppm
NIOSH REL
25 ppm
IDLH Limit
250 ppm

Nitrobenzene

CAS No: 98-95-3
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Nitroethane

CAS No: 79-24-3
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Nitrogen dioxide

CAS No: 10102-44-0
OSHA PEL
5 ppm
NIOSH REL
1 ppm
IDLH Limit
50 ppm

Nitrogen trifluoride

CAS No: 7783-54-2
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

Nitroglycerin

CAS No: 55-63-0
OSHA PEL
0.2 ppm
NIOSH REL
0.1 ppm
IDLH Limit
2 ppm

Nitromethane

CAS No: 75-52-5
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Nitrotoluene (all isomers)

CAS No: N/A
OSHA PEL
5 ppm
NIOSH REL
2 ppm
IDLH Limit
50 ppm

Nitrotrichloromethane; see Chloropicrin

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Octachloronaphthalene

CAS No: 2234-13-1
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Octane

CAS No: 111-65-9
OSHA PEL
500 ppm
NIOSH REL
75 ppm
IDLH Limit
5000 ppm

Oil mist, mineral

CAS No: 8012-95-1
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Organo (alkyl) mercury (Z37.30-1969)

CAS No: 0.01 mg/m3
OSHA PEL
0.04 ppm
NIOSH REL
0.01 ppm
IDLH Limit
0.4 ppm

Osmium tetroxide (as Os)

CAS No: 20816-12-0
OSHA PEL
0.002 mg/m�
NIOSH REL
0.002 ppm
IDLH Limit
0.02 ppm

Oxalic acid

CAS No: 144-62-7
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Oxygen difluoride

CAS No: 7783-41-7
OSHA PEL
0.05 ppm
NIOSH REL
0.05 ppm
IDLH Limit
0.5 ppm

Ozone

CAS No: 10028-15-6
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

PCB; see Chlorodiphenyl (42% and 54% chlorine)

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Paraquat, respirable dust

CAS No: 4685-14-7
OSHA PEL
0.5 mg/m�
NIOSH REL
See Data
IDLH Limit
5 ppm

Parathion

CAS No: 56-38-2
OSHA PEL
0.1 mg/m�
NIOSH REL
0.05 ppm
IDLH Limit
1 ppm

Particulates Not Otherwise Regulated (PNOR)(i)

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Pentaborane

CAS No: 19624-22-7
OSHA PEL
0.005 ppm
NIOSH REL
0.005 ppm
IDLH Limit
0.05 ppm

Pentachloronaphthalene

CAS No: 1321-64-8
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Pentachlorophenol

CAS No: 87-86-5
OSHA PEL
0.5 mg/m�
NIOSH REL
0.5 ppm
IDLH Limit
5 ppm

Pentaerythritol

CAS No: 115-77-5
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Pentane

CAS No: 109-66-0
OSHA PEL
1000 ppm
NIOSH REL
120 ppm
IDLH Limit
10000 ppm

Perchloroethylene (Tetrachloroethylene)

CAS No: 127-18-4
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Perchloromethyl mercaptan

CAS No: 594-42-3
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Perchloryl fluoride

CAS No: 7616-94-6
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Petroleum distillates (Naphtha) (Rubber Solvent)

CAS No: N/A
OSHA PEL
500 ppm
NIOSH REL
350 ppm
IDLH Limit
5000 ppm

Phenol

CAS No: 108-95-2
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Phenyl ether, vapor

CAS No: 101-84-8
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Phenyl ether-biphenyl mixture, vapor

CAS No: N/A
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Phenyl glycidyl ether (PGE)

CAS No: 122-60-1
OSHA PEL
10 ppm
NIOSH REL
1 ppm
IDLH Limit
100 ppm

Phenylethylene; see Styrene

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Phenylhydrazine

CAS No: 100-63-0
OSHA PEL
5 ppm
NIOSH REL
0.14 ppm
IDLH Limit
50 ppm

Phosdrin (Mevinphos)

CAS No: 7786-34-7
OSHA PEL
0.1 mg/m�
NIOSH REL
0.01 ppm
IDLH Limit
1 ppm

Phosgene (Carbonyl chloride)

CAS No: 75-44-5
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Phosphine

CAS No: 7803-51-2
OSHA PEL
0.3 ppm
NIOSH REL
0.3 ppm
IDLH Limit
3 ppm

Phosphoric acid

CAS No: 7664-38-2
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Phosphorus (yellow)

CAS No: 7723-14-0
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Phosphorus pentachloride

CAS No: 10026-13-8
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Phosphorus pentasulfide

CAS No: 1314-80-3
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Phosphorus trichloride

CAS No: 7719-12-2
OSHA PEL
0.5 ppm
NIOSH REL
0.2 ppm
IDLH Limit
5 ppm

Phthalic anhydride

CAS No: 85-44-9
OSHA PEL
2 ppm
NIOSH REL
6 ppm
IDLH Limit
20 ppm

Picloram

CAS No: 1918-0-21
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Picric acid

CAS No: 88-89-1
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Pindone (2-Pivalyl-1,3-indandione)

CAS No: 83-26-1
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Plaster of paris

CAS No: 26499-65-0
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Platinum (as Pt) Metal

CAS No: 7440-06-4
OSHA PEL
Special
NIOSH REL
1 ppm
IDLH Limit
N/A

Portland cement

CAS No: 65997-15-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Propane

CAS No: 74-98-6
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Propylene dichloride

CAS No: 78-87-5
OSHA PEL
75 ppm
NIOSH REL
75 ppm
IDLH Limit
750 ppm

Propylene imine

CAS No: 75-55-8
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Propylene oxide

CAS No: 75-56-9
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Propyne; see Methylacetylene

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Pyrethrum

CAS No: 8003-34-7
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Pyridine

CAS No: 110-86-1
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Quartz: see 1910.1053(m)

CAS No: 14808-60-7
OSHA PEL
Special
NIOSH REL
0.05 ppm
IDLH Limit
N/A

Quinone

CAS No: 106-51-4
OSHA PEL
0.1 ppm
NIOSH REL
0.4 ppm
IDLH Limit
1 ppm

RDX: see Cyclonite

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Respirable dust (as V2O5)

CAS No: N/A
OSHA PEL
0.5 mg/m�
NIOSH REL
0.05 ppm
IDLH Limit
5 ppm

Respirable fraction

CAS No: N/A
OSHA PEL
5 mg/m�
NIOSH REL
See Data
IDLH Limit
50 ppm

Rhodium (as Rh), metal fume and insoluble compounds

CAS No: 7440-16-6
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Rhodium (as Rh), soluble compounds

CAS No: 7440-16-6
OSHA PEL
0.001 mg/m�
NIOSH REL
0.001 ppm
IDLH Limit
0.01 ppm

Ronnel

CAS No: 299-84-3
OSHA PEL
15 mg/m�
NIOSH REL
10 ppm
IDLH Limit
150 ppm

Rotenone

CAS No: 83-79-4
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Rouge

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Selenium compounds (as Se)

CAS No: 7782-49-2
OSHA PEL
0.2 mg/m�
NIOSH REL
0.2 ppm
IDLH Limit
2 ppm

Selenium hexafluoride (as Se)

CAS No: 7783-79-1
OSHA PEL
0.05 ppm
NIOSH REL
0.05 ppm
IDLH Limit
0.5 ppm

Silica, amorphous, diatomaceous earth, containing less than 1% crystalline silica

CAS No: 61790-53-2
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Silica, amorphous, precipitated and gel

CAS No: 112926-00-8
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Silica, crystalline, respirable dust

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Silica, fused, respirable dust

CAS No: 60676-86-0
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Silicates (less than 1% crystalline silica)

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Silicon

CAS No: 7440-21-3
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Silicon carbide

CAS No: 409-21-2
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Silver, metal and soluble compounds (as Ag)

CAS No: 7440-22-4
OSHA PEL
0.01 mg/m�
NIOSH REL
0.01 ppm
IDLH Limit
0.1 ppm

Soapstone

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Soapstone, respirable dust

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Soapstone, total dust

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Sodium fluoroacetate

CAS No: 62-74-8
OSHA PEL
0.05 mg/m�
NIOSH REL
0.05 ppm
IDLH Limit
0.5 ppm

Sodium hydroxide

CAS No: 1310-73-2
OSHA PEL
2 mg/m�
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Soluble Salts

CAS No: N/A
OSHA PEL
0.002 mg/m�
NIOSH REL
0.002 ppm
IDLH Limit
0.02 ppm

Soluble compounds

CAS No: N/A
OSHA PEL
5 mg/m�
NIOSH REL
See Data
IDLH Limit
50 ppm

Starch

CAS No: 9005-25-8
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Stibine

CAS No: 7803-52-3
OSHA PEL
0.1 ppm
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Stoddard solvent

CAS No: 8052-41-3
OSHA PEL
500 ppm
NIOSH REL
350 ppm
IDLH Limit
5000 ppm

Strychnine

CAS No: 57-24-9
OSHA PEL
0.15 mg/m�
NIOSH REL
0.15 ppm
IDLH Limit
1.5 ppm

Styrene

CAS No: 100-42-5
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Styrene (Z37.15-1969)

CAS No: 100 ppm
OSHA PEL
200 ppm
NIOSH REL
50 ppm
IDLH Limit
2000 ppm

Sucrose

CAS No: 57-50-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Sulfur dioxide

CAS No: 7446-09-5
OSHA PEL
5 ppm
NIOSH REL
2 ppm
IDLH Limit
50 ppm

Sulfur hexafluoride

CAS No: 2551-62-4
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Sulfur monochloride

CAS No: 10025-67-9
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Sulfur pentafluoride

CAS No: 5714-22-7
OSHA PEL
0.025 ppm
NIOSH REL
0.01 ppm
IDLH Limit
0.25 ppm

Sulfuric acid

CAS No: 7664-93-9
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Sulfuryl fluoride

CAS No: 2699-79-8
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Systox; see Demeton

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

TEDP (Sulfotep)

CAS No: 3689-24-5
OSHA PEL
0.2 mg/m�
NIOSH REL
0.2 ppm
IDLH Limit
2 ppm

TEPP (Tetraethyl pyrophosphate)

CAS No: 107-49-3
OSHA PEL
0.05 mg/m�
NIOSH REL
0.05 ppm
IDLH Limit
0.5 ppm

Talc (containing asbestos): use asbestos limit: see 29 CFR 1910.1001

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Talc (containing no asbestos), respirable dust

CAS No: 14807-96-6
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Talc; see Silicates

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Tantalum, metal and oxide dust

CAS No: 7440-25-7
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Tellurium and compounds (as Te)

CAS No: 13494-80-9
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Tellurium hexafluoride (as Te)

CAS No: 7783-80-4
OSHA PEL
0.02 ppm
NIOSH REL
0.02 ppm
IDLH Limit
0.2 ppm

Temephos

CAS No: 3383-96-8
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Terphenyls

CAS No: 26140-60-3
OSHA PEL
1 ppm
NIOSH REL
0.5 ppm
IDLH Limit
10 ppm

Tetrachloroethylene

CAS No: 100 ppm
OSHA PEL
200 ppm
NIOSH REL
25 ppm
IDLH Limit
2000 ppm

Tetrachloromethane; see Carbon tetrachloride

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Tetrachloronaphthalene

CAS No: 1335-88-2
OSHA PEL
2 mg/m�
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Tetrachoroethylene; see Perchloroethylene

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Tetraethyl lead (as Pb)

CAS No: 78-00-2
OSHA PEL
0.075 mg/m�
NIOSH REL
0.075 ppm
IDLH Limit
0.75 ppm

Tetrahydrofuran

CAS No: 109-99-9
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

Tetramethyl lead, (as Pb)

CAS No: 75-74-1
OSHA PEL
0.075 mg/m�
NIOSH REL
0.075 ppm
IDLH Limit
0.75 ppm

Tetramethyl succinonitrile

CAS No: 3333-52-6
OSHA PEL
0.5 ppm
NIOSH REL
3 ppm
IDLH Limit
5 ppm

Tetranitromethane

CAS No: 509-14-8
OSHA PEL
1 ppm
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Tetryl (2,4,6-Trinitrophenylmethylnitramine)

CAS No: 479-45-8
OSHA PEL
1.5 mg/m�
NIOSH REL
1.5 ppm
IDLH Limit
15 ppm

Thallium, soluble compounds (as Tl)

CAS No: 7440-28-0
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Thiram

CAS No: 137-26-8
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Tin, inorganic compounds (except oxides) (as Sn)

CAS No: 7440-31-5
OSHA PEL
2 mg/m�
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Tin, organic compounds (as Sn)

CAS No: 7440-31-5
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Titanium dioxide - Total dust

CAS No: 13463-67-7
OSHA PEL
15 mg/m�
NIOSH REL
2.4 ppm
IDLH Limit
150 ppm

Toluene

CAS No: 108-88-3
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Toluene (Z37.12-1967)

CAS No: 200 ppm
OSHA PEL
300 ppm
NIOSH REL
10 ppm
IDLH Limit
3000 ppm

Toluene-2,4-diisocyanate (TDI)

CAS No: 584-84-9
OSHA PEL
0.02 ppm
NIOSH REL
0.02 ppm
IDLH Limit
0.2 ppm

Total dust

CAS No: N/A
OSHA PEL
15 mg/m�
NIOSH REL
See Data
IDLH Limit
150 ppm

Toxaphene; see Chlorinated camphene

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Tremolite

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Tremolite, asbestiform; see 1910.1001

CAS No: N/A
OSHA PEL
3 ppm
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Tributyl phosphate

CAS No: 126-73-8
OSHA PEL
5 mg/m�
NIOSH REL
0.2 ppm
IDLH Limit
50 ppm

Trichloroethylene

CAS No: 79-01-6
OSHA PEL
2 ppm
NIOSH REL
2 ppm
IDLH Limit
20 ppm

Trichloroethylene (Z37.19-1967)

CAS No: 100 ppm
OSHA PEL
200 ppm
NIOSH REL
25 ppm
IDLH Limit
2000 ppm

Trichloromethane; see Chloroform

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Trichloronaphthalene

CAS No: 1321-65-9
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Tridymite; see 1910.1053(m)

CAS No: 15468-32-3
OSHA PEL
Special
NIOSH REL
0.05 ppm
IDLH Limit
N/A

Triethylamine

CAS No: 121-44-8
OSHA PEL
25 ppm
NIOSH REL
25 ppm
IDLH Limit
250 ppm

Trifluorobromomethane

CAS No: 75-63-8
OSHA PEL
1000 ppm
NIOSH REL
1000 ppm
IDLH Limit
10000 ppm

Triorthocresyl phosphate

CAS No: 78-30-8
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Triphenyl phosphate

CAS No: 115-86-6
OSHA PEL
3 mg/m�
NIOSH REL
3 ppm
IDLH Limit
30 ppm

Tripoli (as quartz); see 1910.1053(m)

CAS No: 1317-95-9
OSHA PEL
Special
NIOSH REL
0.05 ppm
IDLH Limit
N/A

Turpentine

CAS No: 8006-64-2
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Uranium (as U)

CAS No: 7440-61-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Vanadium

CAS No: 1314-62-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Vegetable oil mist

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Vinyl benzene; see Styrene

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Vinyl chloride; see 1910.1017

CAS No: 75-01-4
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Vinyl cyanide; see Acrylonitrile

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Vinyl toluene

CAS No: 25013-15-4
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Warfarin

CAS No: 81-81-2
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

Xylenes (o-, m-, p-isomers)

CAS No: 1330-20-7
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

Xylidine

CAS No: 1300-73-8
OSHA PEL
5 ppm
NIOSH REL
2 ppm
IDLH Limit
50 ppm

Yttrium

CAS No: 7440-65-5
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Zinc chloride fume

CAS No: 7646-85-7
OSHA PEL
1 mg/m�
NIOSH REL
1 ppm
IDLH Limit
10 ppm

Zinc oxide

CAS No: 1314-13-2
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Zinc oxide fume

CAS No: 1314-13-2
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

Zinc stearate

CAS No: 557-05-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

Zirconium compounds (as Zr)

CAS No: 7440-67-7
OSHA PEL
5 mg/m�
NIOSH REL
5 ppm
IDLH Limit
50 ppm

a-Chloroacetophenone (Phenacyl chloride)

CAS No: 532-27-4
OSHA PEL
0.05 ppm
NIOSH REL
0.05 ppm
IDLH Limit
0.5 ppm

alpha-Alumina

CAS No: 1344-28-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

alpha-Methyl styrene

CAS No: 98-83-9
OSHA PEL
100 ppm
NIOSH REL
50 ppm
IDLH Limit
1000 ppm

alpha-Naphthylamine; see 1910.1004

CAS No: 134-32-7
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

beta-Chloroprene

CAS No: 126-99-8
OSHA PEL
25 ppm
NIOSH REL
1 ppm
IDLH Limit
250 ppm

beta-Naphthylamine; see 1910.1009

CAS No: 91-59-8
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

beta-Propriolactone; see 1910.1013

CAS No: 57-57-8
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

bis(Chloromethyl) ether; see 1910.1008

CAS No: 542-88-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

m-isomer

CAS No: 99-08-1
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

n-Amyl acetate

CAS No: 628-63-7
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

n-Butyl alcohol

CAS No: 71-36-3
OSHA PEL
100 ppm
NIOSH REL
50 ppm
IDLH Limit
1000 ppm

n-Butyl glycidyl ether (BGE)

CAS No: 2426-08-6
OSHA PEL
50 ppm
NIOSH REL
5.6 ppm
IDLH Limit
500 ppm

n-Butyl-acetate

CAS No: 123-86-4
OSHA PEL
150 ppm
NIOSH REL
150 ppm
IDLH Limit
1500 ppm

n-Hexane

CAS No: 110-54-3
OSHA PEL
500 ppm
NIOSH REL
50 ppm
IDLH Limit
5000 ppm

n-Propyl acetate

CAS No: 109-60-4
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

n-Propyl alcohol

CAS No: 71-23-8
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

n-Propyl nitrate

CAS No: 627-13-4
OSHA PEL
25 ppm
NIOSH REL
25 ppm
IDLH Limit
250 ppm

o-Chlorobenzylidene malononitrile

CAS No: 2698-41-1
OSHA PEL
0.05 ppm
NIOSH REL
0.05 ppm
IDLH Limit
0.5 ppm

o-Dichlorobenzene

CAS No: 95-50-1
OSHA PEL
50 ppm
NIOSH REL
50 ppm
IDLH Limit
500 ppm

o-Methylcyclohexanone

CAS No: 583-60-8
OSHA PEL
100 ppm
NIOSH REL
50 ppm
IDLH Limit
1000 ppm

o-Toluidine

CAS No: 95-53-4
OSHA PEL
5 ppm
NIOSH REL
5 ppm
IDLH Limit
50 ppm

o-isomer

CAS No: 88-72-2
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

p-Benzoquinone; see Quinone

CAS No: N/A
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

p-Dichlorobenzene

CAS No: 106-46-7
OSHA PEL
75 ppm
NIOSH REL
75 ppm
IDLH Limit
750 ppm

p-Nitroaniline

CAS No: 100-01-6
OSHA PEL
1 ppm
NIOSH REL
3 ppm
IDLH Limit
10 ppm

p-Nitrochlorobenzene

CAS No: 100-00-5
OSHA PEL
1 mg/m�
NIOSH REL
See Data
IDLH Limit
10 ppm

p-Phenylene diamine

CAS No: 106-50-3
OSHA PEL
0.1 mg/m�
NIOSH REL
0.1 ppm
IDLH Limit
1 ppm

p-isomer

CAS No: 99-99-0
OSHA PEL
Special
NIOSH REL
See Data
IDLH Limit
N/A

p-tert-Butyltoluene

CAS No: 98-51-1
OSHA PEL
10 ppm
NIOSH REL
10 ppm
IDLH Limit
100 ppm

sec-Amyl acetate

CAS No: 626-38-0
OSHA PEL
125 ppm
NIOSH REL
125 ppm
IDLH Limit
1250 ppm

sec-Butyl acetate

CAS No: 105-46-4
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

sec-Butyl alcohol

CAS No: 78-92-2
OSHA PEL
150 ppm
NIOSH REL
100 ppm
IDLH Limit
1500 ppm

sec-Hexyl acetate

CAS No: 108-84-9
OSHA PEL
50 ppm
NIOSH REL
50 ppm
IDLH Limit
500 ppm

tert-Butyl alcohol

CAS No: 75-65-0
OSHA PEL
100 ppm
NIOSH REL
100 ppm
IDLH Limit
1000 ppm

tert-Butyl chromate (as CrO3)(k); see 1910.1026

CAS No: 1189-85-1
OSHA PEL
Special
NIOSH REL
0.001 ppm
IDLH Limit
N/A

tert-Butyl-acetate

CAS No: 540-88-5
OSHA PEL
200 ppm
NIOSH REL
200 ppm
IDLH Limit
2000 ppm

How the Extended Shift Brief & Scala Model Works

Federal OSHA Permissible Exposure Limits (PELs) established under 29 CFR 1910.1000 assume an 8-hour workday followed by a 16-hour recovery period. When employees work 10-hour or 12-hour shifts:

  • The total daily dose exposure increases.
  • The biological clearance period decreases from 16 hours down to 14 or 12 hours.
  • The permissible limit must be reduced to ensure equivalent biological body burden.
Mathematical Formulation
Reduction Factor (RF) = (8 / h) � ((24 - h) / 16)
Adjusted PEL = Baseline PEL � RF
Hazard Ratio (HR) = Measured Conc / Adjusted PEL

Where h represents the shift duration in hours. For a 12-hour shift, RF = 0.50, effectively halving the allowable workplace air concentration.