Occupational Health and Safety Act, 1993 (Act No. 85 of 1993)

Regulations

Hazardous Chemical Substances Regulations, 1995

Annexure 1

Occupational Exposure Limits - Recommended Limits

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Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Acetaldehyde CH3CHO

100

180

150

270

 

Acetic acid CH3COOH

10

25

15

37

 

Acetic anhydride (CH3CO)20

-

-

5

20

 

Acetone CH3COCH3

750

1780

1500

3560

 

Acetonitrile CH3CN

40

70

60

105

 

o-Acetyl Salicylic Acid (Aspirin) CH3COOC6H4COOH

-

5

-

-

 

Acrolein (Acrylaldehyde) CH2=CHCHO

0.1

0.25

0.3

0.8

 

Acrylic acid CH2=CHCOOH

10

30

20

60

 

Aldrin (ISO) C12H8Cl6

-

0.25

-

0.75

Sk

Allyl Alcohol CH2=CHCH2OH

2

5

4

10

Sk

Allyl Chloride CH2=CHCH2Cl

1

3

2

6

 

1-Allyl-2,3-epoxypropyl ether CH2=CHCH2OCH2CHCH2O

5

22

10

44

Sk

Allyl glycidyl ether (AGE) CH2CHCH2OCH2CHCH2O

5

22

10

44

Sk

Aluminium - Alkyls

-

2

-

-

 

Aluminium - Metal Dust

-

10, 5

-

-

[total inhalable dust] {respirable dust}

Aluminium Oxides Al2O3, Al(OH)3, AlOOH

-

10, 5

-

-

[total inhalable dust] {respirable dust}

Aluminium - Soluble salts

-

2

-

-

 

Aminodimethylbenzene (CH3)2C6H3NH2

2

10

10

50

Sk

2-Aminoethanol NH2CH2CH2OH

3

8

6

15

 

2-Aminopyridine NH2C5H4N

0.5

2

2

8

 

Ammonia NH3

25

17

35

24

 

Ammonium Chloride - Fumes NH4Cl

-

10

-

20

 

Ammonium Sulphamidate NH2SO3NH4

-

10

-

20

 

n-Amyl Acetate CH3COOC5H11

100

530

150

800

 

sec-Amyl Acetate CH3COOCH(CH3)C3H7

-

-

150

800

 

Aniline and homologues C6H5NH2

2

10

5

20

Sk

Anisidine (o & p) isomers NH2C6H4OCH3

0.1

0.5

-

-

Sk

Antimony compounds - as Sb Sb

-

0.5

-

-

 

Arsine AsH3

0.05

0.2

-

-

 

Asphalt - petroleum fumes

-

5

-

10

 

Asprin   CH3COOC6H4COOH

-

5

-

10

 

Atrazine (ISO) C8H4ClN5

-

10

-

-

 

Azinphos-methyl (ISO) (CH3O)2PSSCH2(C7H4N3O)

-

0.2

0.6

-

Sk

Azincine

0.5

1

-

-

Sk

Aziridine CH2CH2NH

-

10

-

-

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

y-BHC (ISO) C6H5Cl6

-

0.5

-

1.5

Sk

Barium soluble compounds as Ba Ba

-

0.5

-

-

 

Barium Sulphate (respirable dust) BaSO4

-

2

-

-

 

Benomyl (ISO) C14H18N4O3

-

10

-

15

 

Benzenethiol C6H5SH

0.5

2

-

-

 

Benzene-1,2,4-tricarboxylic acid 1,2 anhydride C9H4O5

-

0.04

-

-

Sen

p-Benzoquinone C6H4O2

0.1

0.4

0.3

1.2

 

Benzoyl Peroxide (C6H5CO)2O2

-

5

-

-

 

Benzyl butyl phthalate C6H5CH2COOC6H4COOC4H9

-

5

-

-

 

Benzyl Chloride C6H5CH2Cl

1

5

-

-

 

Beryllium and compounds - as Be Be

-

0.002

-

-

 

Biphenyl (C6H5)2

0.2

1.5

0.6

4

 

Bis (2,3-epoxypropyl) ether (OCH2CHCH2)2O

0.1

0.6

-

-

 

Bis-(2-ethylhexyl) phthalate C6H4(COOCH2CH(C2H5)C4H9)2

-

5

-

10

 

2,2 Bis (p-methoxyphenyl)-1,1,1-trichloroethane C16H15Cl3O2

-

10

-

-

 

Bismuth Telluride (Di-Bismuth Tri-Telluride) Bi2Te3

-

5

-

10

 

Bismuth Telluride - Se doped Bi2Te3

-

-

-

10

 

Bornan-2-one C10H16O

2

12

3

18

 

Borates, tetra, Sodium salts Na2B4O7 (.10H2O) (.5H2O)

-

1, 5, 1

-

-

anhydrous, decahydrate, pentahydrate

Boron Oxide   (Diboron Trioxide) B2O3

-

10

-

20

 

Boron Tribromide BBr3

-

-

1

10

 

Boron Triflouride BF3

-

-

1

3

 

Bromacil (ISO) C9H13BrN2O2

1

10

2

20

 

Bromine Br2

0.1

0.7

0.3

2

 

Bromine Pentaflouride BrF5

0.1

0.7

0.3

2

 

Bromochloromethane CH2BrCl

200

1050

250

1300

 

Bromoethane C2H5Br

200

890

250

1110

 

Bromoethylene CH2=CHBr

5

20

-

-

 

Bromoform CHBr3

0.5

5

-

-

Sk

Bromomethane CH3Br

5

20

15

60

Sk

Bromotriflouromethane CF3Br

1000

6100

1200

7300

 

Butane C4H10

600

1430

750

1780

 

Butan-1-ol  C4H9OH

-

-

50

150

Sk

Butan-2-ol  C3H6OHCH3

100

300

150

450

 

Butan-2-one CH3COC2H5

200

590

300

885

 

trans But-2-enal CH3CH=CHCHO

2

6

6

18

 

n-Butyl Acetate CH3COO(CH2)3CH3

150

710

200

950

 

sec-Butyl Acetate CH3COOCH(CH3)CH2CH3

200

950

250

1190

 

tert-Butyl Acetate CH3COOC(CH3)3

200

950

250

1190

 

n-Butyl Acrylate C7H12O2

10

55

-

-

 

n-Butyl Alcohol C4H9OH

-

-

50

150

Sk

sec-Butyl Alcohol CH3CH2CHOHCH3

100

300

150

450

 

tert-Butyl Alcohol (CH3)3COH

100

300

150

450

 

n-Butylamine C4H9NH2

-

-

5

15

Sk

Butyl benzyl phthalate C6H5CH2COOC6H4COOC4H9

-

5

-

-

 

n-Butyl chloroformate ClCO2C4H10

1

5.6

-

-

 

n-Butyl Glycidyl Ether (BGE) C4H9OCH2CHCH2O

25

135

-

-

 

Butyl-2,3-epoxypropyl ether C4H9OCH2CHCH2O

25

135

-

-

 

n-Butyl Lactate C7H14O3

5

25

-

-

 

2-sec-Butylphenol C2H5(CH3)CHC6H4OH

5

30

-

-

Sk

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Caesium hydroxide CsOH

-

2

-

-

 

Calcium Carbonate CaCO3

-

10, 5

-

-

total inhalable dust, respirable dust

Calcium Cyanamide CaNCN

-

0.5

-

1

 

Calcium Hydroxide Ca(OH)2

-

5

-

-

 

Calcium Oxide CaO

-

2

-

-

 

Calcium Silicate

-

10, 5

-

-

total inhalable dust, respirable dust

Camphor - synthetic C10H16O

2

12

3

18

 

Caprolactam dust NH(CH2)5CO

-

1

-

3

 

Caprolactam vapour NH(CH2)5CO

5

20

10

40

 

Captafol (ISO) C10H9Cl4NO2S

-

0.1

-

-

Sk

Captan (ISO) C9H8Cl3NO2S

-

5

-

15

 

Carbaryl (ISO) C10H7OCONHCH3

-

5

-

10

 

Carbofuran (ISO) C12H15NO3

-

0.1

-

-

 

Carbon Black C

-

3.5

-

7

 

Carbon Dioxide CO2

5000

9000

15000

27000

 

Carbon Monoxide CO

50

55

300

330

 

Carbon tetrabromide CBr4

0.1

1.4

0.3

4

 

Carbon Tetrachloride CCl4

2

12.6

-

-

Sk

Carbonyl Chloride COCl2

-

0.4

-

-

Sk

Catechol C6H4(OH)2

5

20

-

-

 

Cellulose

-

10, 5

-

20

total inhalable dust, respirable dust

Cement

-

10, 5

-

-

total inhalable dust, respirable dust

Chlordane (ISO) C10H6Cl8

-

0.5

-

2

Sk

Chlorinated biphenyls  C12H7CI3 (approx)  C6H2CI3C6H3CI2

-

1, 0.5

-

2, 1

42% Cl, 54% Cl

Chlorine Cl2

0.5

1.5

1

3

 

Chlorine Dioxide ClO2

0.1

0.3

0.3

0.9

 

Chlorine Triflouride ClF3

-

-

0.1

0.4

 

Chloroacetaldehyde ClCH2CHO

-

-

1

3

 

2-Chloroacetophenone C6H5COCH2Cl

0.05

0.3

-

-

 

Chloroacetyl Chloride ClCH2COCl

0.05

0.2

-

-

 

Chlorobenzene C6H5Cl

50

230

-

-

 

Chlorobromomethane CH2BrCl

200

1050

250

1300

 

2-Chloro-1,3-butadiene CH2=CClCH=CH2

10

36

-

-

Sk

Chlorodiflouromethane CHClF2

1000

3500

-

-

 

1-Chloro-2,3-epoxypropane OCH2CHCH2Cl

2

8

5

20

Sk

Chloroethane C2H5Cl

1000

2600

1250

3250

 

2-Chloroethanol ClCH2CH2OH

-

-

1

3

Sk

Chloroethylene CH2=CHCl

7

-

-

-

 

Chloroform CHCl3

2

9.8

-

-

Sk

Chloromethane CH3Cl

50

105

100

210

 

1-Chloro-4-nitrobenzene ClC6H4NO2

-

1

-

2

Sk

Chloropentaflouroethane CClF2CF3

1000

6320

-

-

 

Chloropicrin CCl3NO2

0.1

0.7

0.3

2

 

beta-Chloroprene CH2=CClCH=CH2

10

36

-

-

Sk

3-Chloropropene CH2=CHCH2Cl

1

3

2

6

 

Chlorosulphonic acid HSO3Cl

-

1

-

-

 

alpha-Chlorotoluene C6H5CH2Cl

1

5

-

-

 

2-Chlorotoluene C7H7Cl

50

250

-

-

 

2-Cl-6-trichloromethyl pyridine C6H3Cl4N

-

10

-

20

 

Chloropyrifos (ISO) C9H11Cl3NO3PS

-

0.2

-

0.6

Sk

Chromium Cr

-

0.5

-

-

 

Chromium II compounds - as Cr Cr

-

0.5

-

-

 

Chromium III compounds - as Cr Cr

-

0.5

-

-

 

Coal Dust

-

2

-

-

Respirable dust

Coal Tar pitch volatiles - as cyclohexane solubles

-

0.14

-

-

 

Cobalt metal - dust and fumes Co

-

0.1

-

-

 

Copper fumes Cu

-

0.2

-

-

 

Copper dusts and mists - as Cu Cu

-

1

-

2

 

Cotton Dust - raw

-

0.5

-

-

See Annexure 4

Cresol - all isomers CH3C6H4OH

5

22

-

-

Sk

Cristobalite, respirable dust SiO2

 

 

 

 

 

Crotonaldehyde CH3CH=CHCHO

2

6

6

18

 

Cryofluorane (INN) CClF2CClF2

1000

7000

1250

8750

 

Cumene C6H5CH(CH3)2

25

120

75

370

Sk

Cyanamide H2NCN

-

2

-

-

 

Cyanides - as CN

-

5

-

-

Sk

Cyanogen (CN)2

10

20

-

-

 

Cyanogen Chloride ClCN

-

-

0.3

0.6

 

Cychlohexane C6H12

100

340

300

1030

 

Cyclohexanol C6H11OH

50

200

-

-

Sk

Cyclohexanone C6H10O

25

100

100

400

Sk

Cyclohexene C6H10

300

1015

-

-

 

Cyclohexylamine C6H11NH2

10

40

-

-

Sk

Cyclonite (RDX) C3H6N6O6

-

1.5

-

3

Sk

Cyhexatin (ISO) (C6H11)3SnOH

-

5

-

10

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

2,4-D C6H3Cl2OCH2COOH

-

10

-

20

 

DDM H2NC6H4CH2C6H4NH2

0.1

0.8

0.5

4

 

DDT (Dichlorodiphenyltrichloroethane) C14H9Cl5

-

1

-

3

 

DDVP (CH3O)2POOCHCCl2

0.1

1

-

3

Sk

2,4 DES C8H7Cl2NaO5S

-

10

-

20

 

DMDT C16H15Cl3O2

-

10

-

-

 

Derris, commercial C23H22O6

-

5

-

10

 

Diacetone Alcohol CH3COCH2C(CH3)2OH

50

240

75

360

 

Dialkyl 7-9 phthalate C6H4(COOC7-9H15-19)2

-

5

-

-

 

Dialkyl phthalate C6H4(COOCH2CHCH)2

-

5

-

-

 

2,2'-Diaminodiethylamine (NH2CH2CH2)2NH

1

4

-

-

Sk

4,4'-Diaminodiphenylmethane (DADPM) H2NC6H4CH2C6H4NH2

0.1

0.8

0.5

4

 

1,2-Diaminoethane NH2CH2CH2NH2

10

25

-

-

 

Diammonium peroxodisulphate (as S2O8) (NH4)2S2O8

-

1

-

-

 

Diatomaceous earth, respirable dust

-

1.5

-

-

 

Diazinon - (ISO) C12H21N2O3PS

-

0.1

-

0.3

Sk

Diazomethane CH2N2

0.2

0.4

-

-

 

Dibenzoyl peroxide (C6H5CO)2O2

 

5

-

-

 

Diborane B2H6

0.1

0.1

-

-

 

Dibrom   1,2-Dibromo-2,2-dichloroethyldimethyl P C4H7Br2Cl2O4P

-

3

-

6

 

Dibromodiflouromethane CBr2F2

100

860

150

1290

 

Dibutyl Hydrogen Phosphate Di-n-butyl phosphate (n-C4H9O)2(OH)PO

1

5

2

10

 

Dibutyl Phthalate C6H4(CO2C4H9)2

-

5

-

10

 

6,6'Di-tert-butyl-4,4'thiodi-m-cresol C22H30O2S

-

10

-

20

 

Dichloroacetylene ClCCCl

-

-

0.1

0.4

 

1,2-Dichlorobenzene C6H4Cl2

-

-

50

300

 

1,4-Dichlorobenzene C6H4Cl2

25

150

50

300

 

Dichlorobenzene

75

450

-

-

 

Dichloro diflouro methane CCl2F2

1000

4950

1250

6200

 

1,3-Dichloro 5,5-dimethyl hydantoin C5H6Cl2N2O2

-

0.2

-

0.4

 

Dichlorodiphenyltrichloroethane C14H9Cl5

-

1

-

3

 

1,1-Dichloroethane CH3CHCl2

200

810

400

1620

 

1,2-Dichloroethane CH2ClCH2Cl

10

40

15

60

 

1,1-Dichloroethylene CH2CCl2

10

40

-

-

 

1,2-Dichloroethylene
cis:trans  isomers 60:40  ClCH=CHCI

200

790

250

1000

 

Dichloroflouromethane CHCl2F

10

40

-

-

 

2,4-Dichlorophenoxyacetic acid C6H3Cl2OCH2COOH

-

10

-

20

 

1,3-Dichloropropene cis and trans isomers CHClCHCH2Cl

1

5

10

50

Sk

Dichlorotetraflouroethane CClF2CClF2

1000

7000

1250

8750

 

Dichlorvos (ISO) (CH3O)2POOCH=CCl2

0.1

1

0.3

3

Sk

Dicyclohexyl phthalate C6H4(COOC6H11)2

-

5

-

-

 

Dicyclopentadiene C10H12

5

30

-

-

 

Dicyclopentadienyl iron C10H10Fe

-

10

-

20

 

Dieldrin (ISO) C12H8Cl6O

-

0.25

-

0.75

Sk

Diethanolamine HO(CH2)2NH(CH2)2OH

3

15

-

-

 

Diethylamine (C2H5)2NH

10

30

25

75

 

2-Diethylaminoethanol (C2H5)2NCH2CH2OH

10

50

-

-

Sk

Diethylene glycol (HOCH2CH2)2O

23

100

-

-

 

Diethylamine triamine (NH2CH2CH2)2NH

1

4

-

-

Sk

Diethyl ether C2H5OC2H5

400

1200

500

1500

 

Di-(2-ethylhexyl) phthalate (dioctyl phthalate) C6H4(COOCH2CH(C2H5)-C4H9)2

-

5

-

10

 

Diethyl ketone C2H5COC2H5

200

700

250

875

 

Diethyl phthalate C6H4(COOC2H5)2

-

5

-

10

 

Diflourochloromethane CHClF2

1000

3500

-

-

 

Diglycidyl ether (DGE) (OCH2CHCH2)2O

0.1

0.6

-

-

 

o-Dihydroxybenzene C6H4(OH)2

5

20

-

-

 

m-Dihydroxybenzene C6H4(OH)2

10

45

20

90

 

p-Dihydroxybenzene C6H4(OH)2

-

2

-

4

 

1,2-Dihydroxyethane CH2OHCH2OH

-

10

-

60, 125

particulate, vapour

Diisobutyl ketone ((CH3)2CHCH2)2CO

25

150

-

-

 

Diisobutyl phthalate C6H4(COOCH2CH(CH3)2)2

-

5

-

-

 

Diisodecyl phthalate (C10H21CO2)2C6H4

-

5

-

-

 

Diisononyl phthalate C6H4(COOC9H19)2

-

5

-

-

 

Diisooctyl phthalate C6H4(CO2C8H17)2

-

5

-

-

 

Diisopropylamine (CH3)2CHNHCH(CH3)2

5

20

-

-

Sk

Diisopropyl ether (CH3)2CHOCH(CH3)2

250

1050

310

1320

 

Di-linear 79 phthalate C6H4(COOC7-9H15-19)2

-

5

-

-

 

Dimethoxymethane CH2(OCH3)2

1000

3100

1250

3880

 

N,N-Dimethyl acetamide CH3CON(CH3)2

10

36

20

71

Sk

Dimethylamine (CH3)2NH

10

18

-

-

 

NN-Dimethylaniline C6H5N(CH3)2

5

25

10

50

Sk

1,3-Dimethylbutyl acetate CH3CO2CH(CH3)CH2CH-(CH3)2

50

300

100

600

 

NN-Dimethylethylamine C2H5(CH3)2N

10

30

15

45

 

Dimethylformamide HCON(CH3)2

10

30

20

60

Sk

2,6-Dimethylheptan-4-one ((CH3)2CHCH2)2CO

25

150

-

-

 

Dimethyl phthalate C6H4(COOCH3)2

-

5

-

10

 

Dimethyl sulphate (CH3)2SO4

0.1

0.5

0.1

0.5

Sk

Dinitolmide

-

5

-

-

 

Dinitrobenzene all isomers C6H4(NO2)2

0.15

1

0.5

3

Sk

Dinitro-o-cresol CH3C6H2(OH)(NO2)2

-

0.2

-

0.6

Sk

2,4-Dinitrotoluene CH3C6H3(NO2)2

-

1.5

-

5

Sk

Dinonyl phthalate C6H4(COOC9H19)2

-

5

-

-

 

Di-sec-octyl phthalate C6H4(COOCH2CH(C2H5)-C4H9)2

-

5

-

10

 

1,4-Dioxane, tech. grade OCH2CH2OCH2CH2

25

90

100

360

Sk

Dioxathion (ISO) C12H26O6P2S2

-

0.2

-

-

Sk

Diphenyl (C6H5)2

0.2

1.5

0.6

4

 

Diphenylamine (C6H5)2NH

-

10

-

20

 

Diphenyl ether (vapour) C6H5OC6H5

1

7

-

-

 

Diphosphorus pentasulphide P2S5

-

1

-

3

 

Dipotassium peroxodisulphate as S2O8   K2S2O8

-

1

-

-

 

Diquat dibromide (ISO) C12H12Br2N2

-

0.5

-

1

 

Disodium disulphite Na2S2O5

-

5

-

-

 

Disodium peroxodisulphate (measured as S2O8) Na2S2O8

-

1

-

-

 

Disodium tetraborate Na2B4O7 (.10H2O) (.5H2O)

-

1, 5, 1

-

-

anhydrous, decahydrate, pentahydrate

Disulfoton (ISO) (C2H5O)2PSCH2CH2SC2H5

-

0.1

-

0.3

 

Disulphur dichloride S2Cl2

-

 

1

6

 

Disulphur decafluoride S2F10

0.025

0.25

0.075

0.75

 

2,6-Di-tert-butyl-p-cresol   (C4H9)2CH3C6H2OH

-

10

-

-

 

Diuron (ISO)  C9H10Cl2N2O

-

10

-

-

 

Divanadium pentoxide (as V)  V2O5

-

0.5, 0.05

-

-

total inhalable dust, fume & respirable dust

Divinyl benzene   C8H4(CHCH2)2

10

50

-

-

 

Dusts

-

-

-

-

see paragraph 36 of Annexure 1

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Emery

-

10, 5

-

-

total inhalable dust, respirable dust

Endosulfan (ISO) C9H6Cl6O3S

-

0.1

-

0.3

Sk

Endrin (ISO) C12H8Cl6O

-

0.1

-

0.3

Sk

Enflurane CHFClCF2OCF2H

20

150

-

 

 

Epichlorohydrin OCH2CHCH2Cl

2

8

5

20

Sk

1,2-Epoxy-4-epoxyethyl cyclohexane C6H12O2

10

60

-

-

 

2,3-Epoxypropyl isopropyl ether C3H7OCH2CHCH2O

50

240

75

360

 

Ethane-1,2-diol CH2OHCH2OH

-

10, 60

-

125

particulate, vapour

Ethanethiol C2H5SH

0.5

1

2

3

 

Ethanol C2H5OH

1000

1900

-

-

 

Ethanolamine NH2CH2CH2OH

3

8

500

1500

 

Ether C2H5OC2H5

400

1200

-

-

 

Ethyl acetate CH3COOC2H5

400

1400

-

-

 

Ethyl acrylate CH2=CHCOOC2H5

5

20

15

60

Sk

Ethyl alcohol C2H5OH

1000

1900

-

-

 

Ethylamine C2H5NH2

10

18

-

-

 

Ethyl amyl ketone CH3CH2COCH2CH3CHCH2CH3

25

130

-

-

 

Ethyl benzene C6H5C2H5

100

435

125

545

 

Ethyl bromide C2H5Br

200

890

250

1110

 

Ethyl butyl ketone CH3CH2CO(CH2)3CH3

50

230

75

345

 

Ethyl chloride C2H5Cl

1000

2600

1250

3250

 

Ethyl chloroformate ClCO2C2H5

1

4.4

-

-

 

Ethylene

 

 

 

 

 

Ethylene chlorohydrin ClCH2CH2OH

-

-

1

3

Sk

Ethylenediamine NH2CH2CH2NH2

10

25

-

-

 

Ethylene dibromide BrCH2CH2Br

0.5

4

-

-

Sk

Ethylene dichloride CH2CICH2Cl

10

40

15

60

 

Ethylene dinitrate CH2NO3CH2NO3

0.2

1.2

0.2

1.2

Sk

Ethylene glycol CH2OHCH2OH

-

10, 60

-

125

particulate, vapour

Ethylene glycol dinitrate (EGDN) CH2NO3CH2NO3

0.2

1.2

0.2

1.2

Sk

Ethylene glycol monobutyl ether C4H9OCH2CH2OH

25

120

-

-

Sk

Ethylene glycol monoethyl ether C2H5OCH2CH2OH

10

37

-

-

Sk

Ethylene glycol monoethyl ether acetate C2H5OCH2CH2OOCCH3

10

54

-

-

Sk

Ethylene glycol monomethyl ether acetate CH3COOCH2CH2OCH3

5

24

-

-

Sk

Ethylene glycol monomethyl ether CH3OCH2CH2OH

5

16

-

-

Sk

Ethyleneimine CH2CH2NH

0.5

1

-

-

Sk

Ethylene oxide CH2CH2O

5

10

-

-

 

Ethyl ether C2H5OC2H5

400

1200

500

1500

 

Ethyl formate HCOOC2H5

100

300

150

450

 

2-Ethylhexyl chloroformate CICO2(C2H5)CH2CH(CH2)3CH3

1

7.9

-

-

 

Ethylidene dichloride CH3CHCl2

200

810

400

1620

 

Ethyl mercaptan C2H5SH

0.5

1

2

3

 

4-Ethylmorpholine C6H13NO

5

23

20

95

Sk

Ethyl silicate Si(OC2H5)4

10

85

30

255

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Fenchlorphos (ISO) (CH3O)2PSOC6H2Cl3

-

10

-

-

 

Ferbam (ISO) ((CH3)2NCSS)3Fe

-

10

-

20

 

Ferrocene C10H10Fe

-

10

-

20

 

Flourides as F F

-

2.5

-

-

 

Flourine F2

-

-

1

1.5

 

Flourodichloromethane CHCl2F

10

40

-

-

 

Flourotrichloromethane CCl3F

1000

5600

1250

7000

 

Formamide HCONH2

20

30

30

45

 

Formic Acid HCOOH

5

9

-

-

 

Furfural (2-Furaldehyde) C5H4O2

2

8

10

40

Sk

Furfuryl alcohol OCH=CHCH=CCH2OH

5

20

15

60

Sk

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Germanium tetrahydride (Germane) GeH4

0.2

0.6

0.6

1.8

 

Glutaraldehyde OCH(CH2)3CHO

-

-

0.2

0.7

 

Glycerol mist CH2OHCHOHCH2OH

-

10

-

-

 

Glycerol trinitrate CH2NO3CHNO3CH2NO3

0.2

2

0.2

2

Sk

Glycol monoethyl ether C2H5OCH2CH2OH

10

37

0.2

2

Sk

Graphite C

-

10, 5

-

-

total inhalable dust, respirable dust

Guthion (CH3O)2PSSCH2(C7H4N3O)

-

0.2

0.6

-

Sk

Gypsum CaSO4-2H2O

-

10, 5

-

-

total inhalable dust, respirable dust

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Halothane CHBrCI-CF3

10

80

-

-

 

y-HCH (ISO) C6H5Cl6

-

0.5

-

1.5

Sk

Hafnium Hf

-

0.5

-

1.5

 

Halothane CHBrClCF3

10

80

-

-

 

Heptachlor and heptachlor epoxide C10H5Cl7

-

0.5

-

2

Sk

n-Heptane C7H16

400

1600

500

2000

 

Heptan-2-one CH3(CH2)4COCH3

50

240

-

-

 

Heptan-3-one CH3CH2CO(CH2)3CH3

50

230

75

345

 

y-Hexachlorocyclohexane (y-HCH) C6H5Cl6

-

0.5

-

1.5

Sk

Hexachloroethane CCl3CCl3

5

50, 10, 5

-

-

vapour, total inhalable dust, respirable dust

Hexahydro-1,3,5-trinitro-1,3,5-triazine C3H6N6O6

-

1.5

-

3

Sk

Hexane isomers other than n-Hexane C6H14

500

1800

1000

3600

 

n-Hexane C6H14

20

70

-

-

 

1,6-Hexanolactam NH(CH2)5CO

5

20, 1

10

40, 3

vapour, dust

Hexan-2-one C3H9COCH3

5

20

-

-

Sk

Hexone (CH3)2CHCH2COCH3

50

205

75

300

Sk

Hexylene glycol (CH3)2COHCH2CHOHCH3

25

125

25

125

 

Hydrazine NH2NH2

0.1

0.1

-

-

Sk

Hydrazoic acid (as vapour) HN3

-

-

0.1

-

 

Hydrogen bromide HBr

-

-

3

10

 

Hydrogen chloride HCl

-

-

5

7

 

Hydrogen flouride (as F) HF

-

-

3

2.5

 

Hydrogen peroxide H2O2

1

1.5

2

3

 

Hydrogen selenide (as Se) H2Se

0.05

0.2

-

-

 

Hydrogen sulphide H2S

10

14

15

21

 

Hydroquinone C6H4(OH)2

-

2

-

4

 

4-Hydroxy-4-methyl-pentan-2-one CH3COCH2C(CH3)2OH

50

240

75

360

 

2-Hydroxypropyl acrylate CH2CHCOOCH2CHOHCH3

0.5

3

-

-

Sk

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

2,2'-Iminodiethanol HO(CH2)2NH(CH2)2OH

3

15

-

-

 

2,2'-Iminodi(ethylamine) (NH2CH2CH2)2NH

1

4

-

-

Sk

Indene C9H8

10

45

15

70

 

Indium compounds - as In In

-

0.1

-

0.3

 

Iodine I2

-

-

0.1

1

 

Iodoform CHI3

0.6

10

1

20

 

Iodomethane CH3I

5

28

10

56

Sk

Iron Oxide fumes - as Fe  Fe2O3

-

5

-

10

 

Iron pentacarbonyl - as Fe  Fe(CO)5

0.01

0.08

-

-

 

Iron salts soluble - as Fe

-

1

-

2

 

Isoamyl acetate CH3COOCH2CH2CH(CH3)2

100

525

125

655

 

Isoamyl alcohol (CH3)2CHCH2CH2OH

100

360

125

450

 

Isoamyl ethyl ketone CH3COCH2CH2CH(CH3)2

50

240

75

360

 

Isobutyl acetate CH3COOCH2CH(CH3)2

150

700

187

875

 

Isobutyl alcohol (CH3)2CHCH2OH

50

150

75

225

 

Isobutyl methyl ketone (CH3)2CHCH2COCH3

50

205

75

300

Sk

Isoflurane CF3CHClOCHF2

50

380

-

-

 

Isooctyl alcohol (mixed isomers) C8H17OH

50

270

-

-

 

Isopentyl acetate CH3COOCH2CH2CH(CH3)2

100

525

125

655

 

Isophorone C9H14O

-

-

5

25

 

Isophorone diisocyanate (IPDI)

-

0.2

-

0.7

Sen

Isopropyl acetate CH3COOCH(CH3)2

-

-

200

840

 

Isopropyl alcohol (CH3)2CHOH

400

960

500

1225

Sk

Isopropyl benzene C6H5CH(CH3)2

25

120

75

370

 

Isopropyl chloroformate ClCO2CH(CH3)2

1

5

-

-

 

Isopropyl ether (CH3)2CHOCH(CH3)2

250

1050

310

1320

 

Isopropyl glycidyl ether (IGE) C3H7OCH2OCHCH2

50

240

75

360

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Ketene CH2CO

0.5

0.9

1.5

3

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Limestone

-

10, 5

-

-

total inhalable dust, respirable dust

Lindane C6H5Cl6

-

0.5

-

1.9

Sk

Liquified pettroleum gas (LPG) Mixture:
C3H6 : C3H8 : C4H8 : C4H10

1000

1800

1250

2250

 

Lithium hydride LiH

-

0.025

-

-

 

Lithium Hydroxide LiOH

-

-

-

1

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

MbOCA CH2(C6H3ClNH2)2

-

0.005

-

-

Sk

MDA H2NC6H4CH2C6H4NH2

0.1

0.8

0.5

4

 

MDI

-

0.02

-

0.07

Sen

Magnesite

-

10, 5

-

-

total inhalable dust, respirable dust

Magnesium oxide (as Mg) MgO

-

5, 10

-

10

fume and respirable dust, respirable dust

Malathion (ISO) C10H19O6PS2

-

10

-

-

Sk

Maleic anhydride C4H2O3

0.25

1

-

-

 

Manganese dust and compounds Mn

-

5

-

-

 

Manganese fumes Mn

-

1

-

3

 

Manganese cyclopentadienyl tricarbonyl C5HC5-Mn(CO)3

-

0.1

-

0.3

Sk

Manganese tetroxide Mn3O4

-

1

-

-

 

Man made mineral fibre

-

 

-

-

See Annexure 3

Marble

-

10, 5

-

-

Total inhalable dust, respirable dust

Mequinol (INN) CH3OC6H4OH

-

5

-

-

 

Mercaptoacetic acid C2H4O2S

1

5

-

-

 

Mercury - Alkyl compounds as Hg  Hg

-

0.01

-

0.03

Sk

Mercury all other forms - as Hg  Hg

-

0.05

-

0.15

 

Mesityl oxide CH3COCH=C(CH3)2

15

60

25

100

 

Methacrylic acid CH2=C(CH3)COOH

20

70

40

140

 

Methacrylonitrile CH2=C(CH3)CN

1

3

-

-

Sk

Methanethiol CH3SH

0.5

1

-

-

 

Methanol CH3OH

200

260

250

310

Sk

Methomyl (ISO) C5H10N2O2S

-

2.5

-

-

Sk

Methoxychlor (ISO) C16H15Cl3O2

-

10

-

-

 

1-Methoxy propan-2-ol CH3OCH2CHOHCH3

100

360

300

1080

Sk

Methyl acetate CH3COOCH3

200

610

250

760

 

Methyl acrylate CH2=CHCOOCH3

10

35

-

-

Sk

Methylal CH3(OCH3)2

1000

3100

1250

3880

 

Methylal alcohol CH3OH

200

260

250

310

Sk

Methylamine CH3NH2

10

12

-

-

 

Methyl n-amyl ketone CH3(CH2)4COCH3

50

240

-

-

 

N-Methyl aniline C6H5NHCH3

0.5

2

-

-

Sk

Methyl bromide - Skin CH3Br

5

20

15

60

Sk

3-Methylbutan-1-ol (CH3)2CHCH2CH2OH

100

360

125

450

 

1-Methylbutyl acetate CH3COOCH(CH3)C3H7

-

-

150

800

 

Methyl n-butyl ketone CH3(CH2)3COCH3

5

20

-

-

Sk

Methyl chloride CH3Cl

50

105

100

210

 

Methyl chloroform CH3CCl3

350

1900

450

2450

 

Methyl 2-cyanoacrylate CH2=C(CN)COOCH3

2

8

4

16

 

Methylcyclohexane C7H14

400

1600

500

2000

 

Methylcyclohexanol CH3C6H10OH

50

235

75

350

Sk

2-Methylcyclohexanone CH3CHCO(CH2)3CH2

50

230

75

345

Sk

Methylcyclopentadienyl manganese tricarbonyl (as Mn)

-

0.1

-

0.6

 

2-Methyl-4,6-dinitrophenol CH3C6H2(OH)(NO2)2

-

0.2

-

0.6

Sk

4,4'-Methylene bis(2chloroaniline) (MbOCA) CH2(C6H3ClNH2)2

-

0.005

-

-

Sk

Methylene chloride (Dichloromethane) CH2Cl2

100

350

250

780

 

4,4'-Methylene-diphenyl diisocyanate (MDI)

-

0.02

-

0.07

Sen

4,4'-Methylenedianiline (MDA) H2NC6H4CH2C6H4NH2

0.1

0.8

0.5

4

 

Methyl ethyl ketone (MEK) CH3COC2H5

200

590

300

885

 

Methyl ethyl ketone peroxides C8H16O4 or C8H18O6

-

-

0.2

1.5

 

Methyl formate HCOOCH3

100

250

150

375

 

5-Methyl heptan-3-one CH3CH2COCH2CH3CHCH2CH3

25

130

-

-

 

5-Methyl hexan-2-one CH3COCH2CH2CH(CH3)2

50

240

75

360

 

Methyl hydrazine

0.2

0.35

0.2

0.35

Sk

Methyl iodide CH3I

5

28

10

56

Sk

Methyl isoamyl ketone CH3COCH2CH2CH(CH3)2

50

240

75

360

 

Methyl isobutyl carbinol CH3CHOHCH2CH(CH3)2

25

100

40

160

Sk

Methyl isobutyl ketone (MIBK) (CH3)2CHCH2COCH3

50

205

75

300

Sk

Methyl isocyanate

-

0.02

-

0.07

Sen

Methyl mercaptan CH3SH

0.5

1

-

-

 

Methyl methacrylate CH2=C(CH3)COOCH3

100

410

125

510

 

Methyl parathion C8H10NO5PS

-

0.2

-

0.6

Sk

2-Methylpentane-2,4-diol (CH3)2COHCH2CH)HCH3

25

125

25

125

 

4-Methylpentan-2-ol CH3CHOHCH2CH(CH3)2

25

100

40

160

Sk

4-Methylpentan-2-one (CH3)2CHCH2COCH3

50

205

75

300

Sk

4-Methylpent-3-and-2-one CH3COCH=C(CH3)2

15

60

25

100

 

4-Methyl-m-phenylene diisocyanate

-

0.02

-

0.07

Sen

2-Methylpropan-1-ol (CH3)2CHCH2OH

50

150

75

225

 

2-Methylpropan-2-ol (CH3)3COH

100

300

150

450

 

Methyl propyl ketone CH3COC3H7

200

700

250

875

 

1-Methyl-2-pyrrolidone CH3N(CH2)3CO

100

400

-

-

 

Methyl silicate (CH3O)4Si

1

6

5

30

 

alpha Methyl styrene C6H5C(CH3)=CH2

-

-

100

480

 

Methyl styrene (all isomers) CH3C6H4CH=CH2

100

480

150

720

 

n-Methyl-n,2,4,6-tetranitro aniline (NO2)3C6H2N(NO2)CH3

-

1.5

-

3

Sk

Mevinphos (ISO) C7H13O6P

0.01

0.1

0.03

0.3

Sk

Mica

-

10, 1

-

-

total inhalable dust, respirable dust

Molybdenum, soluble compounds as Mo

-

5

-

10

 

Molybdenum, insoluble compounds, as Mo

-

10

-

20

 

Monochloroacetic acid ClCH2CO2H

0.3

1

-

-

Sk

Morpholine C4H9NO

20

70

30

105

Sk

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Naled (ISO) C4H7Br2Cl2O4P

-

3

-

6

Sk

Naphthalene C10H8

10

50

15

75

 

1,5-Napthylene diisocyanate

-

0.02

-

0.07

Sen

Nickel carbonyl Ni(CO)4

-

-

0.1

0.24

 

Nickel, organic compounds (as Ni)

-

1

-

3

 

Nicotine C10H14N2

-

0.5

-

1.5

Sk

Nitrapyrin C6H3Cl4N

-

10

-

20

 

Nitric acid HNO3

2

5

4

10

 

Nitric oxide NO

25

30

35

45

 

4-Nitroaniline NO2C6H4NH2

-

6

-

-

Sk

Nitrobenzene C6H5NO2

1

5

2

10

Sk

Nitroethane C2H5NO2

100

310

-

-

 

Nitrogen dioxide NO2

3

5

5

9

 

Nitrogen monoxide NO

25

30

35

45

 

Nitrogen triflouride NF3

10

30

15

45

 

Nitroglycerin CH2NO2CHNO3CH2NO3

0.2

2

0.2

2

Sk

Nitromethane CH3NO2

100

250

150

375

 

1-Nitropropane C3H7NO2

25

90

-

-

 

2-Nitropropane CH3CH(NO2)CH3

10

36

20

72

 

Nitrotoluene (all isomers) CH3C6H4NO2

5

30

10

60

Sk

Nitrous oxide N2O

100

180

-

-

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Octachloronaphthalene C10Cl8

-

0.1

-

0.3

Sk

n-Octane CH3(CH2)6CH3

300

1450

375

1800

 

Orthophosphoric acid H3PO4

-

1

-

3

 

Osmium tetroxide - as Os  OsO4

0.0002

0.002

0.0006

0.006

 

Oxalic acid COOHCOOH

-

1

-

2

 

Oxalonitrile (CN)2

10

20

-

-

 

2,2'-Oxydiethanol (HOCH2CH2)2O

23

100

-

-

 

Ozone O3

0.1

0.2

0.3

0.6

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

PCB's

-

-

-

-

see chlorinated biphenyls

Paraffin wax fumes

-

2

-

6

 

Paraquat dichloride   (CH3(C5H4N+)2CH3)-(Cl-2)

-

0.1

-

-

Respirable dust

Parathion (ISO) (C2H5O)2PSOC6H4NO2

-

0.1

-

0.3

Sk

Parathion-methyl (ISO) C8H10NO5PS

-

0.2

-

0.6

Sk

Pentacarbonyliron (as Fe)  Fe(CO)5

0.01

0.08

-

-

 

Pentachlorophenol C6Cl5OH

-

0.5

-

1.5

Sk

Pentaerythritol C(CH2OH)4

-

10, 5

-

20

total inhalable dust, respirable dust

Pentane C5H12

600

1800

750

2250

 

2-Pentanone, 3-Pentanone CH3COC2H7

200

700

250

875

 

Pentyl acetate CH3COOC5H11

100

530

150

800

 

Perchloroethylene (Tetrachloroethylene) CCl2=CCl2

50

335

150

1000

 

Perchloryl flouride ClO3F

3

14

6

28

 

Phenacyl chloride C6H5COCH2Cl

0.05

0.3

-

-

 

Phenol C6H5OH

5

19

10

38

Sk

p-Phenylenediamine C6H4(NH2)2

-

0.1

-

-

Sk

Phenyl-2,3-epoxypropyl ether C6H5OCH2CHCH2O

1

6

-

-

 

Phenylethylene C6H5CH=CH2

100

420

250

1050

 

Phenylhydrazine C6H5NHNH2

5

20

10

45

Sk

2-Phenylpropene C6H5C(CH3)=CH2

-

-

100

480

 

Phorate (ISO) C7H17O2PS3

-

0.05

-

0.2

Sk

Phosdrin C7H13O6P

0.01

0.1

0.03

0.3

Sk

Phosgene COCl2

0.1

0.4

-

-

 

Phosphine PH3

-

-

0.3

0.4

 

Phosphorus (yellow) P4

-

0.1

-

0.3

 

Phosphorus pentachloride PCl5

0.1

1

-

-

 

Phosphorus pentasulphide P2S5

-

1

-

3

 

Phosphorus trichloride PCl3

0.2

1.5

0.5

3

 

Phosphoryl trichloride POCl3

0.2

1.2

0.6

3.6

 

Phthallic anhydride C6H4(CO2)O

1

6

4

24

Sen

Picloram (ISO) C6H3Cl3N2O2

-

10

-

20

 

Picric acid HOC6H2(NO2)3

-

0.1

-

0.3

Sk

Piperazine dihydrochloride C4H10N2.2HCl

-

5

-

-

 

Piperidine C5H11N

1

3.5

-

-

Sk

Plaster of Paris (Calcium sulphate) (CaSO4)2H2O

-

10, 5

-

-

total inhalable dust, respirable dust

Platinum metal   Pt

-

5

-

-

 

Platinum, soluble salts - as Pt  Pt

-

0.002

-

-

Sen

Polychlorinated biphenyls

-

 

-

-

See chlorinated biphenyls

Polyvinyl chloride (PVC)

-

10, 5

-

-

total inhalable dust, respirable dust

Portland cement

-

10, 5

-

-

total inhalable dust, respirable dust

Potassium hydroxide KOH

-

-

-

2

 

Propane-1,2-diol CH3CHOHCH2OH

150

470, 10

-

-

vapour + particulates, particulates

n-Propanol CH3CH2CH2OH

200

500

250

625

Sk

Propan-1-ol CH3CH2CH2OH

200

500

250

625

Sk

Propan-2-ol (CH3)2CHOH

400

980

500

1225

Sk

Propargyl alcohol HCCCH2OH

1

2

3

6

Sk

Propionic acid CH3CH2COOH

10

30

15

45

 

Propoxur (ISO) H3CNHCOOC6H4OCH-(CH3)2

-

0.5

-

2

 

n-Propyl acetate CH3COOC3H7

200

840

250

1050

 

Propylene dinitrate CH2NO3CHNO3CH3

0.2

1.2

0.2

1.2

Sk

Propylene glycol CH3CHOHCH2OH

-

-

-

-

See Propane-1,2-diol above

Propylene glycol dinitrate CH2NO3CHNO3CH3

-

-

-

-

See Propylene dinitrate above

Propylene glycol monomethyl ether CH3OCH2CHOHCH3

100

360

300

1080

Sk

Prop-2-yn-1-ol HC=CCH2OH

1

2

3

6

Sk

Pulverised Fuel Ash

-

10, 5

-

-

total inhalable dust, respirable dust

Pyrethrum (Pyrethrins) (ISO)

-

5

-

10

 

Pyridine C5H5N

5

15

10

30

 

2-Pyridylamine NH2C5H4N

0.5

2

2

8

 

Pyrocatechol C6H4(OH)2

5

20

-

-

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Quartz, crystalline SiO2

-

0.4

-

-

respirable dust

Quinone C6H4O2

0.1

0.4

0.3

1.2

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

RDX C3H6N6O8

-

1.5

-

3

Sk

Resorcinol C6H4(OH)2

10

45

20

90

 

Rhodium metal and insoluble compounds - as Rh  Rh

-

0.1

-

0.3

metal fumes and dust

Rhodium, soluble compounds as Rh   Rh

-

0.001

-

0.003

soluble salts

Ronnel  (CH3O)2PSOC6H2Cl3

-

10

-

-

 

Rosin, core solder pyro products - formaldehyde

-

0.1

-

0.3

Sen

Rotenone (commercial) (ISO) C23H22O6

-

5

-

10

 

Rouge

-

10, 5

-

-

total inhalable dust, respirable dust

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Selenium and compounds - as Se  Se

-

0.1

-

-

 

Silane SiH4

0.5

0.7

1

1.5

 

Silica, amourphous SiO2

-

6, 3

-

-

total inhalable dust, respirable dust

Silica, fused SiO2

-

0.1

-

-

respirable dust

Silicon Si

-

10, 5

-

-

Total inhalable dust, respirable dust

Silicon carbide SiC

-

10, 5

-

-

Total inhalable dust, respirable dust

Silicon tetrahydride - Silane SiH4

0.5

0.7

1

1.5

 

Silver metal Ag

-

0.1

-

-

 

Silver, soluble compounds - as Ag Ag

-

0.01

-

-

 

Sodium azide NaN3

-

-

-

0.3

 

Sodium 2,4-dichlorophenoxyethyl sulphate C8H7Cl2NaO3S

-

10

-

20

 

Sodium flouroacetate CH2FCOONa

-

0.05

-

0.15

Sk

Sodium hydrogen sulphite NaHSO3

-

5

-

-

 

Sodium hydroxide NaOH

-

-

-

2

 

Sodium metabisulphite Na2S2O5

-

5

-

-

 

Starch

-

10, 5

-

-

total inhalable dust, respirable dust

Stibine SbH3

0.1

0.5

0.3

1.5

 

Strychnine C21H22N2O3

-

0.15

-

0.45

 

Styrene, monomer C6H5CHCH2

100

420

250

1050

 

Subtilisins (proteolytic enzymes)

-

0.00006

-

0.00008

 

Sucrose C12H22O11

-

10

-

20

 

Sulfotep (ISO) (C2H5)4P2S2O5

-

0.2

-

-

Sk

Sulphur dioxide SO2

2

5

5

15

 

Sulphur hexaflouride SF6

1000

6000

1250

7500

 

Sulphuric acid H2SO4

-

1

-

-

 

Sulphur monochloride S2Cl2

-

-

1

6

 

Sulphur pentachloride S2F10

0.025

0.25

0.075

0.75

 

Sulphur tetraflouride SF4

0.1

0.4

0.3

1

 

Sulphuryl flouride (Sulphuryl diflouride) SO2F2

5

20

10

40

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

2,4,5-T (ISO) C8H5Cl3O3

-

10

-

20

 

TDI

-

0.02

-

0.07

Sen

TEDP (Tetraethyl dithiopyrophosphate) (C2H5)4P2S2O5

-

0.2

-

-

Sk

TEPP (ISO) (Tetraethyl pyrophosphate) (C2H5)4P2O7

0.004

0.05

0.01

0.2

Sk

Talc (containing no asbestos fibers)

-

10, 1

-

-

total inhalable dust, respirable dust

Tantalum metal and oxide dusts - as Ta  Ta

-

5

-

10

 

Tellurium and compounds - as Te  Te

-

0.1

-

-

except Hydrogen Telluride

Terphenyls, all isomers C18H14

-

-

0.5

5

 

1,1,2,2-Tetrabromoethane CHBr2CHBr2

0.5

7

-

-

Sk

Tetrabromomethane CBr4

0.1

1.4

0.3

4

 

Tetracarbonylnickel (as Ni) Ni(CO)4

-

-

0.1

0.24

 

1,1,1,2-Tetrachloro-2,2-diflouroethane CCl3CClF2

100

834

100

834

 

1,1,2,2-Tetrachloro-1,2-diflouroethane CCl2FCCl2F

100

834

100

834

 

Tetrachloroethene CCl2CCl2

50

335

150

1000

 

Tetrachloromethane CCI4

2

12.6

-

-

Sk

Tetrachloronaphthalene, all isomers C10H4Cl4

-

2

-

4

 

O,O,O',O'-Tetraethyl dithiopyrophosphate (C2H5)4P2S2O5

-

0.2

-

-

Sk

O,O,O',O'-Tetraethyl pyrophosphate (C2H5)4P2O7

0.004

0.05

0.01

0.2

Sk

Tetraethyl orthosilicate Si(OC2H5)4

10

85

30

255

 

Tetraflourodichloroethane CClF2CClF2

1000

7000

1250

8750

 

Tetrahydrofuran (C2H4)2O

200

590

250

735

 

Tetramethyl orthosilicate (CH3O)4Si

1

6

5

30

 

Tetramethyl succinonitrile C8H12N2

0.5

3

2

9

Sk

Tetrasodium pyrophosphate Na4P2O7

-

5

-

-

Sk

Tetryl (NO2)3C6H2N(NO2)CH3

-

1.5

-

3

Sk

Thallium, soluble compounds Tl

-

0.1

-

-

Sk

4,4'-Thio bis(6-tert butyl-m-cresol) C22H30O2S

-

10

-

20

 

Thioglycolic acid C2H4O2S

1

5

-

-

 

Thionyl chloride SOCl2

-

-

1

5

 

Thiram (ISO) (CH3)2NCS2CS2N(CH3)2

-

5

-

10

 

Tin, oxide and inorganics except SnH4 Sn

-

2

-

4

 

Tin, organic compounds as Sn except Cyhexatin  Sn

-

0.1

-

0.2

Sk

Titanium dioxide   TiO2

-

10, 5

-

-

total inhalable dust, respirable dust

Toluene C6H5CH3

50

188

150

560

Sk

Toluene, 2,4 diisocyanate (TDI)

-

0.02

-

0.07

Sen

p-Toluenesulphonyl chloride CH3C6H4SO2Cl

-

-

-

5

 

1,4,7-Tri-(aza)-heptane (NH2CH2CH2)2OH

1

4

-

-

Sk

Tribromomethane CHBr3

0.5

5

-

-

Sk

Tributyl phosphate, all isomers (C4H9)3PO4

-

5

-

5

 

Tricarbonyl (eta-cyclopentadienyl) manganese (as Mn)  (C5H5)-Mn(CO)3

-

0.1

-

0.3

Sk

Tricarbonyl (methylcyclopentadienyl) manganese (as Mn)  (CH3)C5H4)-Mn(CO)3

-

0.2

-

0.6

Sk

Trichloroacetic acid CCl3COOH

1

5

-

-

 

1,2,4-Trichlorobenzene C6H3Cl3

5

40

5

40

 

1,1,1-Trichlorobis (chlorophenyl) ethane C14H9Cl5

-

1

-

3

 

1,1,2-Trichloroethane CH2ClCHCl2

10

45

20

90

Sk

Trichloroflouromethane CClF3

1000

5600

1250

7000

 

Trichloromethane CHCl3

2

9.8

-

-

 

Trichloronitromethane CCl3NO2

0.1

0.7

0.3

2

 

2,4,5-Trichlorophenoxy acetic acid C8H5Cl3O3

-

10

-

20

 

1,2,3-Trichloropropane CH2ClCHClCH2Cl

50

300

75

450

Sk

1,1,2-Trichloro-1,2,2-triflouroethane CCl2FCClF2

1000

7600

1250

9500

 

Tri-o-Cresyl phosphate (CH3C6H4O)3PO

-

0.1

-

0.3

 

Tricyclohexyl tin hydroxide (C6H11)3SnOH

-

5

-

10

 

Tridymite SiO2

-

0.4

-

-

respirable dust

Triethylamine (C2H5)3N

10

40

15

60

 

Triflourobromomethane CF3Br

1000

6100

1200

7300

 

Trimanganese tetraoxide Mn3O

-

1

-

-

 

Trimellitic anhydride C9H4O5

-

0.04

-

-

Sen

Trimethylamine (CH3)3N

10

24

15

36

 

Trimethylbenzene all isomers and mixtures C6H3(CH3)3

25

123

-

 

 

3,5,5-Trimethylcyclohex-2-enone C9H14O

-

-

5

25

 

Trimethyl phosphite (CH3O)3P

2

10

-

-

 

2,4,6-Trinitrophenol HOC6H2(NO2)3

-

0.1

-

0.3

Sk

2,4,6-Trinitrotoluene (TNT) CH3C6H2(NO2)3

-

0.5

-

-

Sk

Triphenyl phosphate (C6H5)3PO4

-

3

-

6

 

Tripoli, respirable dust SiO2

-

0.4

-

-

 

Tri-o-tolyl phosphate (CH3C6H4O)3PO

-

0.1

-

0.3

 

Tungsten, insoluble compounds - as W  W

-

5

-

10

 

Tungsten, soluble compounds - as W  W

-

1

-

3

 

Turpentine  C10H16

100

560

150

840

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Uranium, all compounds - as U  U

-

0.2

-

0.6

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Vanadium pentoxide V2O5

-

0.5, 0.05

-

-

total inhable, fume and respirable dust

Vinyl acetate CH3COOCHCH2

10

30

20

60

 

Vinyl benzene C6H5CH=CH2

100

420

250

1050

 

Vinyl bromide CH2CHBr

5

20

-

-

 

Vinyl chloride

5

15

-

-

 

4-Vinyl cyclohexene

0.1

0.4

-

-

 

Vinyl cyclohexene dioxide C6H12O2

10

60

-

-

 

Vinyl toluene C6H5C(CH3)CH2

-

-

100

480

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Warfarin (ISO) C19H16O4

-

0.1

-

0.3

 

White spirit

100

575

125

720

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Xylene, all and mixed isomers  C6H4(CH3)2

100

435

150

650

Sk

Xylidene, mixed isomers  (CH3)2C6H3NH2

2

10

10

50

Sk

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Yttrium, as metal and compounds  Y

-

1

-

3

 

 

Substance

TWA OEL-RL ppm

TWA OEL-RL mg/m³

Short Term OEL-RL ppm

Short Term OEL-RL mg/m³

1995 Notes

Zinc chloride fumes   ZnCl2

-

1

-

2

 

Zinc di-stearate   Zn(C18H35O2)2

-

10, 5

-

20

total inhalable dust, respirable dust

Zinc oxide fumes   ZnO

-

5

-

10

 

Zirconium and compounds - as Zr  Zr

-

5

-

10