Exposure limits are reported in ppm, mg/m3, or f/cc. In general, substances present in air as a vapour or gas are reported in parts per million (ppm). Substances present in air as an aerosol (dust, fume, mist) and mixtures such as diesel fuel are typically reported in milligrams per cubic meter (mg/m3). Fibrous substances, such as synthetic vitreous fibers (e.g., glass wool fibers) are reported in fibers per cubic centimeter (f/cc).
Notations column
The notations identify substances considered to be carcinogens, sensitizers and those with adverse reproductive effect. The notations column also indicates substances that contribute significantly to overall exposure by the skin route.
TWA column
This is the 8-hour time weighted average (TWA) limit, as defined in OHS Regulations.
STEL/Ceiling column
This is the short-term exposure limit or STEL, which is defined in the OHS Regulations.
Any missing compounds may be available – CDC NIOSH Pocket Guide.
Exposure Limits Chart
| Substance [CAS No.] | TWA | STEL/Ceiling | Notations |
|---|---|---|---|
| Abate (See Temephos) | |||
| Acetaldehyde [75-07-0] Revised 2014 | C 25 ppm | A2, 2B | |
| Acetamide [60-35-5] | 2B | ||
| Acetic acid [64-19-7] | 10 ppm | 15 ppm | |
| Acetic anhydride [108-24-7] Revised 2011 | 1 ppm | 3 ppm | |
| Acetone [67-64-1] | 250 ppm | 500 ppm | |
| Acetone cyanohydrin [75-86-5] | C 1 ppm | Skin | |
| Acetonitrile [75-05-8] | 20 ppm | Skin | |
| Acetophenone [98-86-2] | 10 ppm | ||
| Acetylene [74-86-2] | Simple asphyxiant | ||
| Acetylene tetrabromide (See 1,1,2,2 Tetrabromoethane) | |||
| Acetylsalicylic acid (Aspirin) [50-78-2] | 5 mg/m3 | ||
| Acrolein [107-02-8] | C 0.1 ppm | Skin | |
| Acrylamide, Inhalable [79-06-1] Revised 2005 | 0.03 mg/m3 (V) | Skin; 2A | |
| Acrylic acid [79-10-7] | 2 ppm | Skin; R | |
| Acrylonitrile [107-13-1] | 2 ppm | Skin; 2B | |
| Adipic acid [124-04-9] | 5 mg/m3 | ||
| Adiponitrile [111-69-3] | 2 ppm | Skin | |
| Alachlor, Inhalable [15972-60-8] Revised 2007 | 1.0 mg/m3(V) | S | |
| Aldrin, Inhalable [309-00-2] Revised 2007 | 0.05mg/m3(V) | Skin | |
| Aliphatic hydrocarbon gases [C1-C4] Revised 2004 | 1000 ppm | ||
| Allyl alcohol [107-18-6] | 0.5 ppm | Skin | |
| Allyl amine [107-11-9] | 2 ppm | ||
| Allyl bromide [106-95-6] | (I) | ||
| Allyl chloride [107-05-1] Revised 2011 | 1 ppm | 2 ppm | Skin |
| Allyl glycidyl ether [106-92-3] | 1 ppm | S | |
| Allyl propyl disulfide [2179-59-1] Revised 2006 | 0.5 ppm | S | |
| Aluminum metal and insoluble compounds [7429-90-5] , Respirable, Revised 2008 | 1.0 mg/m3 | ||
| 4-Aminodiphenyl [92-67-1] | (L) | Skin; A1, 1 | |
| 2-Aminopyridine [504-29-0] | 0.5 ppm | ||
| Amitrole [61-82-5] Revised 2006 | 0.2 mg/m3 | R | |
| Ammonia [7664-41-7] | 25 ppm | 35 ppm | |
| Ammonium chloride – Fume [12125-02-9] | 10 mg/m3 | 20 mg/m3 | |
| Ammonium perfluorooctanoate [3825-26-1] | 0.01 mg/m3 | Skin | |
| Ammonium sulfamate [7773-06-0] | 10 mg/m3(N) | ||
| tert-Amyl methyl ether (TAME) [994-05-8] | 20 ppm | R | |
| Aniline [62-53-3] | 2 ppm | Skin | |
| o-Anisidine [90-04-0] | 0.5 mg/m3 | Skin; 2B | |
| p-Anisidine [104-94-9] | 0.5 mg/m3 | Skin | |
| Antimony and compounds, as Sb [7440-36-0] | 0.5 mg/m3 | ||
| Antimony hydride (Stibine) [7803-52-3] | 0.1 ppm | ||
| Antimony trioxide – Production [1309-64-4] | (L) | A2, 2B | |
| ANTU [86-88-4] | 0.3 mg/m3 | ||
| Argon [7440-37-1] | Simple asphyxiant | ||
| Arsenic and inorganic compounds, as As [7440-38-2] | 0.01 mg/m3 | A1, 1 | |
| Arsine [7784-42-1] Revised 2007 | 0.005 ppm | ||
| Asbestos – All forms [1332-21-4] | 0.1 f/cc (F) | A1, 1 | |
| Asphalt (Bitumen) fume, as benzene-soluble aerosol, Inhalable [8052-42-4] | 0.5 mg/m3 | (I) | |
| Atrazine [1912-24-9] | 5 mg/m3 | ||
| Azinphos-methyl, Inhalable [86-50-0] | 0.2 mg/m3(V) | Skin; S | |
| Barium and soluble compounds, as Ba [7440-39-3] | 0.5 mg/m3 | ||
| Barium sulfate [7727-43-7] | 10 mg/m3(N) | ||
| Benomyl, Inhalable [17804-35-2] Revised 2008 | 1 mg/m3 | R, S | |
| Benz[a]anthracene [56-55-3] Revised 2006 | (L) | A2, 2B | |
| Benzene [71-43-2] | 0.5 ppm | 2.5 ppm | Skin; A1, 1 |
| Benzidine [92-87-5] | (L) | Skin; A1, 1 | |
| Benzidine based dyes | 2A | ||
| Benzo[b]fluoranthene [205-99-2] | (L) | A2, 2B | |
| Benzo[a]pyrene [50-32-8] Revised 2006 | (L) | A2, 1 | |
| Benzotrichloride [98-07-7] | C 0.1 ppm | Skin; A2, 2A | |
| Benzoyl chloride [98-88-4] | C 0.5 ppm | 2A | |
| Benzoyl peroxide [94-36-0] | 5 mg/m3 | ||
| Benzyl acetate [140-11-4] | 10 ppm | ||
| Benzyl chloride [100-44-7] | C 1 ppm | 2A | |
| Beryllium and compounds, Inhalable, as Be [7440-41-7] Revised 2009; 2010; 2015 | 0.00005 mg/m3 | Skin; S; A1, 1; (I) | |
| Biphenyl [92-52-4] | 0.2 ppm | ||
| Bis(2-dimethylaminoethyl) ether (DMAEE) [3033-62-3] | 0.05 ppm | 0.15 ppm | Skin |
| Bismuth telluride – Se-doped [1304-82-1] | 5 mg/m3 | ||
| Bismuth telluride – Undoped [1304-82-1] | 10 mg/m3(N) | ||
| Borate compounds, Inorganic, Inhalable [1303-96-4; 1330-43-4; 10043-35-3; 12179-04-3] Revised 2005 | 2 mg/m3 | 6 mg/m3 | |
| Boron oxide [1303-86-2] | 10 mg/m3 | ||
| Boron tribromide [10294-33-4] | C 1 ppm | ||
| Boron trifluoride [7637-07-02] | C 1 ppm | ||
| Bromacil [314-40-9] | 10 mg/m3 | ||
| Bromine [7726-95-6] | 0.1 ppm | 0.2 ppm | |
| Bromine pentafluoride [7789-30-2] | 0.1 ppm | ||
| Bromochloromethane [74-97-5] | 200 ppm | 250 ppm | |
| Bromoform [75-25-2] Revised 2009 | 0.5 ppm | ||
| 1-Bromopropane [106-94-5] Revised 2005 | 10 ppm | R | |
| 1,3-Butadiene [106-99-0] | 2 ppm | A2, 1 | |
| n-Butane [106-97-8] | 600 ppm | 750 ppm | |
| n-Butanol [71-36-3] | 15 ppm | C 30 ppm | |
| sec-Butanol [78-92-2] | 100 ppm | ||
| tert-Butanol [75-65-0] | 100 ppm | ||
| Butenes, all isomers, including Isobutene [106-98-9; 107-01-7; 590-18-1; 624-64-6; 25167-67-3; 115-11-7] | (I) | ||
| 2-Butoxyethanol (EGBE) [111-76-2] Revised 2003 | 20 ppm | ||
| 2-Butoxyethyl acetate [112-07-2] Revised 2003 | 20 ppm | ||
| n-Butyl acetate [123-86-4] | 20 ppm | ||
| sec-Butyl acetate [105-46-4] | 200 ppm | ||
| tert-Butyl acetate [540-88-5] | 200 ppm | ||
| n-Butyl acrylate [141-32-2] | 2 ppm | S | |
| n-Butylamine [109-73-9] | C 5 ppm | Skin | |
| Butylated hydroxytoluene (BHT), Inhalable, (2,6-Di-tert-butyl-p-cresol) [128-37-0] | 2 mg/m3(V) | ||
| tert-Butyl chromate, as CrO3 [1189-85-1] | C 0.1 mg/m3 | Skin | |
| n-Butyl glycidyl ether (BGE) [2426-08-6] Revised 2005 | 3 ppm | Skin; S; R | |
| n-Butyl lactate [138-22-7] | 5 ppm | ||
| n-Butyl mercaptan [109-79-5] | 0.5 ppm | R | |
| n-Butyl methacrylate [97-88-1] | 50 ppm | ||
| o-sec-Butylphenol [89-72-5] | 5 ppm | Skin | |
| p-tert-Butyltoluene [98-51-1] | 1 ppm | ||
| Cadmium and compounds, as Cd [7440-43-9] | 0.01 mg/m3 | A2, 1 | |
| Cadmium and compounds, Respirable, as Cd [7440-43-9] | 0.002 mg/m3 | A2, 1 | |
| Calcium arsenate, as As [7778-44-1] | 0.01 mg/m3 | A1, 1 | |
| Calcium carbonate (incl. Limestone, Marble) [1317-65-3] | 10 mg/m3(N) | 20 mg/m3 | |
| Calcium chromate, as Cr [13765-19-0] | 0.001 mg/m3 | A2, 1 | |
| Calcium cyanamide [156-62-7] | 0.5 mg/m3 | ||
| Calcium hydroxide [1305-62-0] | 5 mg/m3 | ||
| Calcium oxide [1305-78-8] | 2 mg/m3 | ||
| Calcium silicate – Synthetic nonfibrous [1344-95-2] | 10 mg/m3(E,N) | ||
| Calcium sulfate, Inhalable [7778-18-9] | 10 mg/m3 | ||
| Camphor – Synthetic [76-22-2] | 2 ppm | 3 ppm | |
| Caprolactam, Dust [105-60-2] | 1 mg/m3 | 3 mg/m3 | |
| Captafol [2425-06-1] | 0.1 mg/m3 | Skin; 2A; S | |
| Captan, Inhalable [133-06-2] | 5 mg/m3 | S | |
| Carbaryl [63-25-2] Revised 2008; 2010 | 5 mg/m3 | Skin; R | |
| Carbofuran, Inhalable [1563-66-2] Revised 2004 | 0.1 mg/m3(V) | ||
| Carbon black, Inhalable [1333-86-4] Revised 2011 | 3 mg/m3 | 2B | |
| Carbon dioxide [124-38-9] | 5000 ppm | 15,000 ppm | |
| Carbon disulfide [75-15-0] | 4 ppm | 12 ppm | Skin |
| Carbon monoxide [630-08-0] | 25 ppm | 100 ppm | R |
| Carbon tetrabromide [558-13-4] | 0.1 ppm | 0.3 ppm | |
| Carbon tetrachloride [56-23-5] | 2 ppm | Skin; A2, 2B | |
| Carbonyl fluoride [353-50-4] | 2 ppm | 5 ppm | |
| Carbonyl sulfide [463-58-1] Revised 2015 | 5 ppm | ||
| Catechol [120-80-9] | 5 ppm | Skin; 2B | |
| Cellulose [9004-34-6] | 10 mg/m3(N) | ||
| Cesium hydroxide [21351-79-1] | 2 mg/m3 | ||
| Chlordane [57-74-9] | 0.5 mg/m3 | Skin; 2B | |
| Chlorinated camphene [8001-35-2] | 0.5 mg/m3 | 1 mg/m3 | Skin; 2B |
| o-Chlorinated diphenyl oxide [31242-93-0] | 0.5 mg/m3 | ||
| Chlorine [7782-50-5] | 0.5 ppm | 1 ppm | |
| Chlorine dioxide [10049-04-4] | 0.1ppm | 0.3 ppm | |
| Chlorine trifluoride [7790-91-2] | C 0.1 ppm | ||
| Chloroacetaldehyde [107-20-0] | C 1 ppm | ||
| Chloroacetic acid [79-11-8] | 0.3 ppm | ||
| Chloroacetone [78-95-5] | C 1 ppm | Skin | |
| 2-Chloroacetophenone [532-27-4] | 0.05 ppm | S | |
| Chloroacetyl chloride [79-04-9] | 0.05 ppm | 0.15 ppm | Skin |
| p-Chloroaniline [106-47-8] | 2B | ||
| Chlorobenzene [108-90-7] | 10 ppm | ||
| o-Chlorobenzylidene malononitrile [2698-41-1] | C 0.05 ppm | Skin | |
| Chlorobromomethane (see Bromochloromethane) | |||
| 1-Chloro-1,1-difluoroethane [75-68-3] | 1000 ppm | ||
| Chlorodifluoromethane [75-45-6] | 500 ppm | 1250 ppm | |
| Chlorodiphenyl (42% chloride) [53469-21-9] | 1 mg/m3 | Skin; 2A | |
| Chlorodiphenyl (54% chloride) [11097-69-1] | 0.5 mg/m3 | Skin; 2A | |
| Chloroform [67-66-3] | 2 ppm | 2B; R | |
| bis(Chloromethyl) ether [542-88-1] | 0.001 ppm | A1, 1 | |
| Chloromethyl methyl ether [107-30-2] | (L) | A2, 1 | |
| 1-Chloro-1-nitropropane [600-25-9] | 2 ppm | ||
| Chloropentafluoroethane [76-15-3] | 1000 ppm | ||
| Chloropicrin [76-06-2] | 0.1 ppm | ||
| 1-Chloro-2-propanol [127-00-4] Revised 2008 | 1 ppm | Skin; R | |
| 2-Chloro-1-propanol [78-89-7] Revised 2008 | 1 ppm | Skin; R | |
| beta-Chloroprene [126-99-8] | 10 ppm | Skin; 2B; R | |
| 2-Chloropropioni acid [598-78-7] | 0.1 ppm | Skin; R | |
| o-Chlorostyrene [2039-87-4] | 50 ppm | 75 ppm | |
| o-Chlorotoluene [95-49-8] | 50 ppm | ||
| 4-Chloro-o-Toluidine [95-69-2] | 2A | ||
| Chlorotrifluoromethane [75-72-9] | 1000 ppm | ||
| Chlorpyrifos, Inhalable [2921-88-2] Revised 2003 | 0.1 mg/m3(V) | Skin | |
| Chromite ore processing (Chromate), as Cr | 0.05 mg/m3 | A1 | |
| Chromium – Metal [7440-47-3] | 0.5 mg/m3 | ||
| Chromium (III) inorganic compounds, as Cr [7440-47-3] | 0.5 mg/m3 | ||
| Chromium (VI) inorganic compounds – Insoluble, as Cr [7440-47-3] | 0.01 mg/m3 | A1, 1 | |
| Chromium (VI) inorganic compounds – Water soluble, as Cr [7440-47-3] | 0.025 mg/m3 | C 0.1 mg/m3 | A1, 1 |
| Chromyl chloride [14977-61-8] | 0.025 ppm | ||
| Chrysene [218-01-9] Revised 2006 | (L) | 2B | |
| Citral, inhalable [5292-40-5] | (I) | ||
| Clopidol [2971-90-6] | 10 mg/m3(N) | ||
| Coal dust – Anthracite, Respirable | 0.4 mg/m3 | ||
| Coal dust – Bituminous, Respirable | 0.9 mg/m3 | ||
| Coal tar pitch volatiles, as benzene-soluble aerosol [65996-93-2] | 0.2 mg/m3 | A1, 1 | |
| Cobalt and inorganic compounds, as Co [7440-48-4] | 0.02 mg/m3 | 2B | |
| Cobalt carbonyl, as Co [10210-68-1] | 0.1 mg/m3 | 2B | |
| Cobalt hydrocarbonyl, as Co [16842-03-8] | 0.1 mg/m3 | 2B | |
| Copper – Dusts and mists, as Cu [7440-50-8] | 1 mg/m3 | ||
| Copper – Fume, as Cu [7440-50-8] | 0.2 mg/m3 | ||
| Cotton dust – Raw, Untreated, Thoracic, Revised 2011 | 0.1 mg/m3 | ||
| Coumaphos, Inhalable [56-72-4] Revised 2006 | 0.05 mg/m3 (V) | Skin | |
| Cresol, all isomers [1319-77-3; 95-48-7; 108-39-4; 106-44-5] | 10 mg/m3 | Skin | |
| Crotonaldehyde [4170-30-3] | C 0.3 ppm | Skin | |
| Crufomate [299-86-5] | 5 mg/m3 | ||
| Cumene [98-82-8] | 25 ppm | 75 ppm | 2B |
| Cyanamide [420-04-2] | 2 mg/m3 | ||
| Cyanogen [460-19-5] | 10 ppm | ||
| Cyanogen bromide [506-68-3] | (I) | ||
| Cyanogen chloride [506-77-4] | C 0.3 ppm | ||
| Cyclohexane [110-82-7] | 100 ppm | ||
| Cyclohexanol [108-93-0] | 50 ppm | Skin | |
| Cyclohexanone [108-94-1] Revised 2003 | 20 ppm | 50 ppm | Skin |
| Cyclohexene [110-83-8] | 300 ppm | ||
| Cyclohexylamine [108-91-8] | 10 ppm | ||
| Cyclonite [121-82-4] | 0.5 mg/m3 | Skin | |
| Cyclopentadiene [542-92-7] | 75 ppm | ||
| Cyclopentane [287-92-3] | 600 ppm | ||
| Cyhexatin [13121-70-5] | 5 mg/m3 | ||
| 2,4-D (2,4-Dichlorophenoxy-acetic acid) [94-75-7] (see 2,4-Dichlorophenoxyacetic acid and its esters) | |||
| DDT (Dichloro-diphenyltrichloroethane) [50-29-3] | 1 mg/m3 | 2B | |
| Decaborane [17702-41-9] | 0.05 ppm | 0.15 ppm | Skin |
| Demeton, Inhalable [8065-48-3] | 0.05 mg/m3 (V) | Skin | |
| Demeton-S-methyl, Inhalable [919-86-8] | 0.05 mg/m3 (V) | Skin; S | |
| Diacetone alcohol [123-42-2] | 50 ppm | ||
| Diacetyl [431-03-8] Revised 2015 | 0.01 ppm | 0.02 ppm | |
| 2,4-Diaminoanisole [615-05-4] | 2B | ||
| 2,4-Diaminotoluene [95-80-7] | 2B | ||
| Diazinon, Inhalable [333-41-5] Revised 2003 | 0.01 mg/m3 (V) | Skin | |
| Diazomethane [334-88-3] | 0.2 ppm | A2 | |
| Diborane [19287-45-7] | 0.1 ppm | ||
| 1,2-Dibromo-3-chloropropane [96-12-8] | 2B | ||
| 2-N-Dibutylaminoethanol [102-81-8] | 0.5 ppm | Skin | |
| Dibutyl phenyl phosphate [2528-36-1] | 0.3 ppm | Skin | |
| Dibutyl phosphate [107-66-4] Revised 2009; 2010 | 1 ppm | 2 ppm | Skin |
| Dibutyl phthalate [84-74-2] | 5 mg/m3 | R | |
| Dichloroacetic acid [79-43-6] Revised 2005 | 0.5 ppm | Skin; 2B; R | |
| Dichloroacetylene [7572-29-4] | C 0.1 ppm | ||
| o-Dichlorobenzene [95-50-1] | 25 ppm | 50 ppm | |
| p-Dichlorobenzene [106-46-7] | 10 ppm | 2B | |
| 3,3′-Dichlorobenzidine [91-94-1] | (L) | Skin; 2B | |
| 1,4-Dichloro-2-butene [764-41-0] | 0.005 ppm | Skin; A2 | |
| 2,2-Dichlorodiethyl sulfide (Mustard Gas) [505-60-2] | 1 | ||
| Dichlorodifluoromethane [75-71-8] | 1000 ppm | ||
| 1,3-Dichloro-5,5-dimethyl hydantoin [118-52-5] | 0.2 mg/m3 | 0.4 mg/m3 | |
| 1,1-Dichloroethane [75-34-3] | 100 ppm | ||
| 1,2-Dichloroethane (see ethylene dichloride) | |||
| 1,2-Dichloroethylene, all isomers [540-59-0; 156-59-2; 156-60-5] | 200 ppm | ||
| Dichloroethyl ether [111-44-4] | 5 ppm | 10 ppm | Skin |
| Dichlorofluoromethane [75-43-4] | 10 ppm | ||
| Dichloromethane [75-09-2] | 25 ppm | 2B | |
| 2,2′-Dichloro-n-methyldiethylamine (Nitrogen mustard) [51-75-2] | 2A | ||
| 1,1-Dichloro-1-nitroethane [594-72-9] | 2 ppm | ||
| 1,3-Dichloropropene [542-75-6] | 1 ppm | Skin; 2B | |
| 2,4-Dichlorophenoxyacetic acid and its esters [94-75-7] Revised 2006 | 10 mg/m3 | 20 mg/m3 | (I) |
| 2,2-Dichloropropionic acid, Inhalable [75-99-0] | 5 mg/m3 | ||
| Dichlorotetrafluoroethane (Cryofluorane) [76-14-2] | 1000 ppm | ||
| Dichlorvos (DDVP), Inhalable [62-73-7] | 0.1 mg/m3(V) | Skin; 2B; S | |
| Dicrotophos, Inhalable [141-66-2] | 0.05 mg/m3 (V) | Skin | |
| Dicyclohexylmethane-4,4′-diisocyanate [5124-30-1] (see Methylene bis (4-cyclohexyl-isocyanate)) | |||
| Dicyclopentadiene [77-73-6] | 5 ppm | ||
| Dicyclopentadienyl iron [102-54-5] | 10 mg/m3(N) | ||
| Dieldrin [60-57-1] | 0.25 mg/m3 | Skin | |
| Diesel fuel, as total hydrocarbons, Inhalable [68334-30-5; 68476-30-2; 68476-31-3; 68476-34-6; 77650-28-3] | 100 mg/m3(V) | Skin; (I) | |
| Diethanolamine [111-42-2] Revised 2009; 2010 | 2 mg/m3 | Skin; 2B | |
| Diethylamine [109-89-7] | 5 ppm | 15 ppm | Skin |
| 2-Diethylaminoethanol [100-37-8] | 2 ppm | Skin | |
| Diethylene triamine [111-40-0] | 1 ppm | Skin; S | |
| Di(2-ethylhexyl)phthalate (DEHP) [117-81-7] | 5 mg/m3 | 2B | |
| Diethyl ketone [96-22-0] | 200 ppm | 300 ppm | |
| Diethyl phthalate [84-66-2] | 5 mg/m3 | ||
| Diethyl sulfate [64-67-5] | 2A | ||
| Diethylene glycol monobutyl ether [112-34-5] | (I) | ||
| N,N-Diethylhydroxylamine [3710-84-7] | (I) | ||
| Difluorodibromomethane [75-61-6] | 100 ppm | ||
| Diglycidyl ether (DGE) [2238-07-5] Revised 2007 | 0.01 ppm | R | |
| Diisobutyl ketone [108-83-8] | 25 ppm | ||
| Diisocyanates, not elsewhere specified, NOS | 0.005 ppm | C 0.01ppm | |
| Diisopropylamine [108-18-9] | 5 ppm | Skin | |
| 3,3′-Dimethoxybenzidine [119-90-4] | 2B | ||
| Dimethoxymethane [109-87-5] | 1000 ppm | 1250 ppm | |
| N,N-Dimethylacetamide [127-19-5] | 10 ppm | Skin; R | |
| Dimethylamine [124-40-3] | 5 ppm | 15 ppm | |
| Dimethylaniline [121-69-7] | 5 ppm | 10 ppm | Skin |
| 3,3′-Dimethylbenzidine [119-93-7] | 2B | ||
| Dimethyl carbamoyl chloride [79-44-7] Revised 2007 | 0.005 ppm | Skin; A2, 2A | |
| Dimethyl disulfide [624-92-0] Revised 2007 | 0.5 ppm | Skin | |
| Dimethyl ether [115-10-6] | 1000 ppm | ||
| Dimethylethoxysilane [14857-34-2] | 0.5 ppm | 1.5 ppm | |
| Dimethylformamide [68-12-2] | 10 ppm | Skin | |
| 1,1-Dimethylhydrazine [57-14-7] | 0.01 ppm | Skin; 2B | |
| 1,2-Dimethylhydrazine [540-73-8] | 2A | ||
| Dimethyl phthalate [131-11-3] | 5 mg/m3 | ||
| Dimethyl sulfate [77-78-1] | C 0.1 ppm | Skin; 2A | |
| Dimethyl sulfide [75-18-3] Revised 2004 | 10 ppm | ||
| Dinitolmide [148-01-6] (See 3,5-Dinitro-o-toluamide) | |||
| Dinitrobenzene, all isomers [528-29-0; 99-65-0; 100-25-4; 25154-54-5] | 0.15 ppm | Skin | |
| Dinitrol-o-cresol [534-52-1] | 0.2 mg/m3 | Skin | |
| 3,5-Dinitro-o-toluamide [148-01-6] Revised 2007 | 1 mg/m3 | ||
| Dinitrotoluene [25321-14-6] | 0.2 mg/m3 | Skin; 2B; (I); R | |
| n-Dioctyl phthalate [117-84-0] | 5 mg/m3 | ||
| 1,4-Dioxane [123-91-1] | 20 ppm | Skin; 2B | |
| Dioxathion, Inhalable [78-34-2] | 0.1 mg/m3(V) | Skin | |
| 1,3-Dioxolane [646-06-0] | 20 ppm | R | |
| Diphenylamine [122-39-4] | 10 mg/m3 | ||
| Dipropyl ketone [123-19-3] | 50 ppm | ||
| Dipropylene glycol methyl ether [34590-94-8] | 100 ppm | 150 ppm | Skin |
| Diquat, Inhalable [2764-72-9] | 0.5 mg/m3 | Skin | |
| Diquat, Respirable [2764-72-9] | 0.1 mg/m3 | Skin | |
| Disulfiram [97-77-8] | 2 mg/m3 | ||
| Disulfoton, Inhalable [298-04-4] | 0.05 mg/m3 (V) | Skin | |
| Diuron [330-54-1] | 10 mg/m3 | ||
| Divinyl benzene [1321-74-0] | 10 ppm | ||
| Dodecyl mercaptan [112-55-0] Revised 2004 | 0.1 ppm | S | |
| Dyfonate, Inhalable [944-22-9] Revised 2006 | 0.1 mg/m3(V) | Skin | |
| Endosulfan [115-29-7] Revised 2009; 2010 | 0.1 mg/m3 | Skin | |
| Endrin [72-20-8] | 0.1 mg/m3 | Skin | |
| Enflurane [13838-16-9] | 2 ppm | ||
| Epichlorohydrin [106-89-8] | 0.1 ppm | Skin; 2A; R | |
| EPN, Inhalable [2104-64-5] Revised 2003 | 0.1 mg/m3 | Skin | |
| Ethane [74-84-0] Revised 2004 See Aliphatic Hydrocarbon gases [C1-C4] Revised 2008 | |||
| Ethanol [64-17-5] Revised 2009 | 1000 ppm | ||
| Ethanolamine [141-43-5] | 3 ppm | 6 ppm | |
| Ethion, Inhalable [563-12-2] Revised 2003 | 0.05 mg/m3 | Skin | |
| 2-Ethoxyethanol (EGEE) [110-80-5] | 5 ppm | Skin; R | |
| 2-Ethoxyethyl acetate (EGEEA) [111-15-9] | 5 ppm | Skin; R | |
| Ethyl acetate [141-78-6] | 150 ppm | ||
| Ethyl acrylate [140-88-5] | 5 ppm | 15 ppm | 2B; S |
| Ethylamine [75-04-7] | 5 ppm | 15 ppm | Skin |
| Ethyl amyl ketone [541-85-5] Revised 2007 | 10 ppm | ||
| Ethyl benzene [100-41-4] Revised 2011 | 20 ppm | 2B | |
| Ethyl bromide [74-96-4] | 5 ppm | Skin | |
| Ethyl tert-butyl ether (ETBE) [637-92-3] | 5 ppm | R | |
| Ethyl butyl ketone [106-35-4] | 50 ppm | 75 ppm | |
| Ethyl chloride [75-00-3] | 100 ppm | Skin | |
| Ethyl cyanoacrylate [7085-85-0] | 0.2 ppm | ||
| Ethyl methacrylate [97-63-2] | 50 ppm | ||
| Ethylene [74-85-1] Revised 2005 | 200 ppm | ||
| Ethylene chlorohydrin [107-07-3] | C 1 ppm | Skin | |
| Ethylenediamine [107-15-3] | 10 ppm | Skin; S | |
| Ethylene dibromide [106-93-4] | 0.5 ppm | Skin; 2A | |
| Ethylene dichloride (1,2-dichloroethane) [107-06-2] | 1 ppm | 2 ppm | 2B |
| Ethylene glycol – Aerosol [107-21-1] | C 100 mg/m3 | ||
| Ethylene glycol – Particulate [107-21-1] | 10 mg/m3 | 20 mg/m3 | |
| Ethylene glycol – Vapour [107-21-1] | C 50 ppm | ||
| Ethylene glycol dinitrate (EGDN) [628-96-6] | 0.05 ppm | Skin | |
| Ethylene oxide [75-21-8] | 0.1 ppm | 1 ppm | A2, 1; R |
| Ethyleneimine [151-56-4] Revised 2009; 2010 | 0.5 ppm | Skin; 2B | |
| Ethyl ether [60-29-7] | 400 ppm | 500 ppm | |
| Ethyl formate [109-94-4] Revised 2015 | 100 ppm | ||
| 2-Ethylhexanoic acid, Inhalable [149-57-5] | 5 mg/m3(V) | R | |
| Ethylidene norbornene [16219-75-3] | C 5 ppm | ||
| Ethyl isocyanate [109-90-0] | (I) | ||
| Ethyl mercaptan [75-08-1] | 0.5 ppm | ||
| N-Ethylmorpholine [100-74-3] | 5 ppm | Skin | |
| Ethyl silicate [78-10-4] | 10 ppm | ||
| Fenamiphos, Inhalable [22224-92-6] Revised 2006 | 0.05 mg/m3 (V) | Skin | |
| Fensulfothion, Inhalable [115-90-2] Revised 2005 | 0.01 mg/m3 (V) | Skin | |
| Fenthion, Inhalable [55-38-9] Revised 2006 | 0.05 mg/m3 (V) | Skin | |
| Ferbam, Inhalable [14484-64-1] Revised 2009 | 5 mg/m3 | ||
| Ferrovanadium dust [12604-58-9] | 1 mg/m3 | 3 mg/m3 | |
| Flour dust, Inhalable | 0.5 mg/m3 | S | |
| Fluorides (as F) | 2.5 mg/m3 | ||
| Fluorine [7782-41-4] | 0.1 ppm | ||
| Fluroxene [406-90-6] | 2 ppm | ||
| Fonofos (see Dyfonate) [944-22-9] | |||
| Formaldehyde [50-00-0] | 0.3 ppm | C 1 ppm | A2, 1; S |
| Formamide [75-12-7] | 10 ppm | Skin | |
| Formic acid [64-18-6] | 5 ppm | 10 ppm | |
| Furfural [98-01-1] | 2 ppm | Skin | |
| Furfuryl alcohol [98-00-0] | 5 ppm | 10 ppm | Skin |
| Gallium arsenide, Respirable [1303-00-0] Revised 2005 | 0.0003 mg/m3 | 1 | |
| Gasoline [86290-81-5] | 300 ppm | 500 ppm | 2B |
| Germanium tetrahydride [7782-65-2] | 0.2 ppm | ||
| Glutaraldehyde, Activated & inactivated [111-30-8] | C 0.05 ppm | S | |
| Glycerin – mist [56-81-5] | 10 mg/m3 | ||
| Glycerin – mist, Respirable [56-81-5] | 3 mg/m3 | ||
| Glycidol [556-52-5] | 2 ppm | 2A | |
| Glyoxal, Inhalable [107-22-2] | 0.1 mg/m3(V) | S | |
| Grain dust (oat, wheat, barley) | 4 mg/m3(E) | ||
| Graphite – All forms except graphite fibres, Respirable [7782-42-5] | 2 mg/m3 | ||
| Gypsum [13397-24-5] | 10 mg/m3(N) | 20 mg/m3 | |
| Hafnium and compounds, as Hf [7440-58-6] | 0.5 mg/m3 | ||
| Halothane [151-67-7] | 2 ppm | R | |
| Helium [7440-59-7] | Simple asphyxiant | ||
| Heptachlor [76-44-8] | 0.05 mg/m3 | Skin; 2B | |
| Heptachlor epoxide [1024-57-3] | 0.05 mg/m3 | Skin | |
| Heptane (n-Heptane) [142-82-5] | 400 ppm | 500 ppm | |
| Hexachlorobenzene (HCB) [118-74-1] | 0.002 mg/m3 | Skin; 2B | |
| Hexachlorobutadiene [87-68-3] | 0.02 ppm | Skin | |
| Hexachlorocyclopentadiene [77-47-4] | 0.01 ppm | ||
| Hexachloroethane [67-72-1] | 1 ppm | Skin; 2B | |
| Hexachloronaphthalene [1335-87-1] | 0.2 mg/m3 | Skin | |
| Hexafluoroacetone [684-16-2] | 0.1 ppm | Skin; R | |
| Hexafluoropropylene [116-15-4] Revised 2007 | 0.1 ppm | ||
| Hexahydrophthalic anhydride, all isomers, Inhalable [85-42-7; 13149-00-3; 14166-21-3] Revised 2004 | C 0.005 mg/m3 (V) | S | |
| Hexamethyl phosphoramide [680-31-9] | Skin; 2B | ||
| Hexamethylene diisocyanate (HDI) [822-06-0] | 0.005 ppm | C 0.01 ppm | S |
| n-Hexane [110-54-3] | 20 ppm | Skin | |
| Hexane, all isomers except n-Hexane | 200 ppm | ||
| 1,6-Hexanediamine [124-09-4] | 0.5 ppm | ||
| 1-Hexene [592-41-6] | 50 ppm | R | |
| sec-Hexyl acetate [108-84-9] | 50 ppm | ||
| Hexylene glycol [107-41-5] | C 25 ppm | ||
| Hydrazine [302-01-2] | 0.01 ppm | Skin; 2B | |
| Hydrogen [1333-74-0] | Simple asphyxiant | ||
| Hydrogenated terphenyls – Nonirradiated [61788-32-7] | 0.5 ppm | ||
| Hydrogen bromide [10035-10-6] Revised 2004 | C 2 ppm | ||
| Hydrogen chloride [7647-01-0] Revised 2006 | C 2 ppm | ||
| Hydrogen cyanide, as CN [74-90-8] | C 4.7 ppm | Skin | |
| Cyanide salts, as CN [592-01-8; 151-50-8; 143-33-9] | C 5 mg/m3 | Skin | |
| Hydrogen fluoride, as F [7664-39-3] | C 2 ppm | ||
| Hydrogen peroxide [7722-84-1] | 1 ppm | ||
| Hydrogen selenide [7783-07-5] | 0.05 ppm | ||
| Hydrogen sulfide [7783-06-4] | C 10 ppm | ||
| Hydroquinone [123-31-9] Revised 2008 | 1 mg/m3 | S | |
| 2-Hydroxypropyl acrylate [999-61-1] | 0.5 ppm | Skin; S | |
| Indene [95-13-6] Revised 2008; 2010 | 10 ppm | ||
| Indium and compounds, as In [7440-74-6] | 0.1 mg/m3 | 2B; (I) | |
| Iodides | (I) | ||
| Iodine [7553-56-2] Revised 2008; 2010 | C 0.1 ppm | ||
| Iodoform [75-47-8] | 0.6 ppm | ||
| Iron oxide dust, as Fe [1309-37-1] | 5 mg/m3 | ||
| Iron oxide fume , as Fe [1309-37-1] | 5 mg/m3 | 10 mg/m3 | |
| Iron pentacarbonyl [13463-40-6] | 0.01 ppm | ||
| Iron salts – soluble, as Fe | 1 mg/m3 | 2 mg/m3 | |
| Isoamyl alcohol [123-51-3] | 100 ppm | 125 ppm | |
| Isobutanol [78-83-1] | 50 ppm | ||
| Isobutyl acetate [110-19-0] | 150 ppm | ||
| Isobutyl nitrite, Inhalable [542-56-3] | C 1 ppm (V) | ||
| Isooctyl alcohol [26952-21-6] | 50 ppm | Skin | |
| Isophorone [78-59-1] | C 5 ppm | ||
| Isophorone diisocyanate [4098-71-9] | 0.005 ppm | C 0.01 ppm | S |
| Isopropanol (Isopropyl alcohol) [67-63-0] Revised 2003 | 200 ppm | 400 ppm | |
| 2-Isopropoxyethanol [109-59-1] | 25 ppm | Skin | |
| Isopropyl acetate [108-21-4] Revised 2003 | 100 ppm | 200 ppm | |
| Isopropylamine [75-31-0] | 5 ppm | 10 ppm | |
| N-Isopropylaniline [768-52-5] | 2 ppm | Skin | |
| Isopropyl ether [108-20-3] | 250 ppm | 310 ppm | |
| Isopropyl glycidyl ether (IGE) [4016-14-2] | C 50 ppm | ||
| Kaolin, Respirable [1332-58-7] | 2 mg/m3(E) | ||
| Kerosene [8008-20-6]/Jet fuels [64742-47-8], as total hydrocarbon vapour, Revised 2006 | 200 mg/m3(P) | Skin | |
| Ketene [463-51-4] | 0.5 ppm | 1.5 ppm | |
| Lead – elemental and inorganic compounds, as Pb [7439-92-1] | 0.05 mg/m3 | Elemental 2B; R Other inorganic 2A; R | |
| Lead chromate, as Cr [7758-97-6] | 0.012 mg/m3 | A2, 1; R; (I) | |
| Lead chromate, as Pb [7758-97-6] | 0.05 mg/m3 | A2, 1; R; (I) | |
| Lindane [58-89-9] | 0.5 mg/m3 | Skin | |
| Liquified petroleum gas (L.P.G.) [68476-85-7] | 1000 ppm | 1250 ppm | |
| Lithium hydroxide [1310-65-2] | C 1 mg/m3 | ||
| Lithium hydride [7580-67-8] | 0.025 mg/m3 | ||
| Magnesite [546-93-0] Revised 2006 (See Particles Not Otherwise Classified (PNOC)) | |||
| Magnesium oxide (fume), Inhalable [1309-48-4] Revised 2003 | 10 mg/m3 | ||
| Magnesium oxide, Respirable dust and fume, as Mg [1309-48-4] | 3 mg/m3 | 10 mg/m3 | |
| Malathion, Inhalable [121-75-5] Revised 2003 | 1 mg/m3(V) | Skin | |
| Maleic anhydride [108-31-6] | 0.1 ppm | S | |
| Manganese – Elemental & inorganic compounds, as Mn [7439-96-5] | 0.2 mg/m3 | R | |
| Manganese cyclopentadienyl tricarbonyl, as Mn [12079-65-1] | 0.1 mg/m3 | Skin | |
| Mercury – Alkyl compounds, as Hg [7439-97-6] | 0.01 mg/m3 | 0.03 mg/m3 | Skin |
| Mercury – Aryl compounds, as Hg [7439-97-6] | 0.05 mg/m3 | C 0.1 mg/m3 | Skin |
| Mercury – Elemental, as Hg [7439-97-6] | 0.025 mg/m3 | Skin; R | |
| Mercury – Inorganic compounds, as Hg [7439-97-6] | 0.025 mg/m3 | Skin; R | |
| Mercury – Methyl, as Hg [7439-97-6] | 0.01 mg/m3 | 0.03 mg/m3 | Skin; 2B |
| Mesityl oxide [141-79-7] | 10 ppm | 25 ppm | |
| Methacrylic acid [79-41-4] | 20 ppm | ||
| Methane [74-82-8] Revised 2004 See Aliphatic Hydrocarbon gases [C1-C4] Revised 2008 | |||
| Methanol [67-56-1] | 200 ppm | 250 ppm | Skin |
| Methomyl [16752-77-5] | 2.5 mg/m3 | ||
| Methoxychlor [72-43-5] | 10 mg/m3 | ||
| 2-Methoxyethanol (EGME) [109-86-4] Revised 2006 | 0.1 ppm | Skin; R | |
| 2-Methoxyethyl acetate (EGMEA) [110-49-6] Revised 2006 | 0.1 ppm | Skin; R | |
| Methoxyflurane [76-38-0] | 2 ppm | ||
| 4-Methoxyphenol [150-76-5] | 5 mg/m3 | ||
| 1-Methoxy-2-propanol (PGME) [107-98-2] | 50 ppm | 75 ppm | |
| 2-Methoxy-1-propanol [1589-47-5] | 20 ppm | 40 ppm | |
| 1-Methoxypropyl-2-acetate [108-65-6] | 50 ppm | 75 ppm | |
| 2-Methoxypropyl-1-acetate [70657-70-4] | 20 ppm | 40 ppm | |
| bis-(2-Methoxypropyl) ether (DPGME) (see Dipropylene glycol methyl ether) [34590-94-8] | |||
| Methyl acetate [79-20-9] | 200 ppm | 250 ppm | |
| Methyl acetylene [74-99-7] | 1000 ppm | ||
| Methyl acetylene-propadiene mixture (MAPP) [59355-75-8] | 1000 ppm | 1250 ppm | |
| Methyl acrylate [96-33-3] | 2 ppm | Skin; S | |
| Methylacrylonitrile [126-98-7] | 1 ppm | Skin | |
| Methylal (see Dimethoxymethane) [109-87-5] | |||
| Methylamine [74-89-5] | 5 ppm | 15 ppm | |
| Methyl n-amyl ketone [110-43-0] | 50 ppm | ||
| N-Methyl aniline [100-61-8] | 0.5 ppm | Skin | |
| Methyl bromide [74-83-9] | 1 ppm | Skin | |
| Methyl tert-butyl ether (MTBE) [1634-04-4] | 50 ppm | R | |
| Methyl n-butyl ketone [591-78-6] Revised 2008 | 5 ppm | 10 ppm | Skin; R |
| Methyl chloride [74-87-3] | 50 ppm | 100 ppm | Skin; R |
| Methyl chloroform [71-55-6] | 350 ppm | 450 ppm | |
| Methyl 2-cyanoacrylate [137-05-3] | 0.2 ppm | ||
| Methylcyclohexane [108-87-2] | 400 ppm | ||
| Methylcyclohexanol [25639-42-3] | 50 ppm | ||
| o-Methylcyclohexanone [583-60-8] | 50 ppm | 75 ppm | Skin |
| 2-Methylcyclopentadienyl manganese tricarbonyl, as Mn [12108-13-3] | 0.2 mg/m3 | Skin | |
| Methyl demeton, Inhalable [8022-00-2] Revised 2007 | 0.05 mg/m3 (V) | Skin | |
| Methylene bisphenyl isocyanate (MDI) [101-68-8] | 0.005 ppm | C 0.01 ppm | Skin; S |
| 4,4′-Methylene bis(2-chloroaniline) (MBOCA; MOCA) [101-14-4] Revised 2009 | 0.01 ppm | Skin; A2, 1 | |
| Methylene bis (4-cyclo-hexyl-isocyanate), [5124-30-1] | 0.005 ppm | C 0.01 ppm | |
| Methylene chloride (See Dichloromethane) | |||
| 4,4′-Methylene dianiline [101-77-9] | 0.01 ppm | Skin; 2B | |
| Methyl ethyl ketone (MEK) [78-93-3] | 50 ppm | 100 ppm | |
| Methyl ethyl ketone peroxide (MEKP) [1338-23-4] | C 0.2 ppm | ||
| Methyl formate [107-31-3] | 100 ppm | 150 ppm | Skin |
| Methyl hydrazine [60-34-4] | 0.01 ppm | Skin | |
| Methyl iodide [74-88-4] | 2 ppm | Skin | |
| Methyl isoamyl ketone [110-12-3] | 50 ppm | ||
| Methyl isobutyl carbinol [108-11-2] | 25 ppm | 40 ppm | Skin |
| Methyl isobutyl ketone [108-10-1] Revised 2011 | 20 ppm | 75 ppm | 2B |
| Methyl isocyanate [624-83-9] | 0.02 ppm | Skin; S | |
| Methyl isopropyl ketone [563-80-4] Revised 2011 | 20 ppm | ||
| Methyl mercaptan [74-93-1] | 0.5 ppm | ||
| Methyl methacrylate [80-62-6] | 50 ppm | 100 ppm | S |
| 1-Methyl naphthalene [90-12-0] Revised 2007 | 0.5 ppm | Skin | |
| 2-Methyl naphthalene [91-57-6] Revised 2007 | 0.5 ppm | Skin | |
| Methyl parathion [298-00-0] Revised 2009; 2010 | 0.2 mg/m3 | Skin | |
| Methyl propyl ketone (2-pentanone) [107-87-9] | 150 ppm | 250 ppm | |
| Methyl silicate [681-84-5] | 1 ppm | ||
| alpha-Methyl styrene [98-83-9] Revised 2015 | 10 ppm | R; 2B | |
| Methyl vinyl ketone [78-94-4] | C 0.2 ppm | Skin; S | |
| Metribuzin [21087-64-9] | 5 mg/m3 | ||
| Mevinphos, Inhalable [7786-34-7] Revised 2003 | 0.01 mg/m3 (V) | Skin | |
| Mica, Respirable [12001-26-2] | 3 mg/m3 | ||
| Molybdenum – Metal and insoluble compounds, Respirable [7439-98-7] | 3 mg/m3 | ||
| Molybdenum – Metal and insoluble compounds, Inhalable [7439-98-7] | 10 mg/m3 | ||
| Molybdenum – Soluble compounds, as Mo, Respirable [7439-98-7] | 0.5 mg/m3 | ||
| Monochloroacetic acid [79-11-8] See Chloroacetic acid | |||
| Monocrotophos, Inhalable [6923-22-4] | 0.05 mg/m3 (V) | Skin | |
| Morpholine [110-91-8] | 20 ppm | Skin | |
| Naled, Inhalable [300-76-5] | 0.1 mg/m3(V) | Skin; S | |
| Naphthalene [91-20-3] | 10 ppm | 15 ppm | Skin; 2B |
| 1,5-Naphthalene diisocyanate [3173-72-6] | 0.005 ppm | C 0.01 ppm | |
| beta-Naphthylamine [91-59-8] | (L) | A1, 1 | |
| Natural gas [8006-14-2] Revised 2004 See Aliphatic Hydrocarbon gases [C1-C4] Revised 2008 | |||
| Natural rubber latex, as total proteins, Inhalable [9006-04-6] Revised 2004; 2008; 2010 | 0.001 mg/m3 | Skin; S | |
| Neon [7440-01-9] | Simple asphyxiant | ||
| Nickel – Insoluble inorganic compounds, as Ni [7440-02-0] | 0.05 mg/m3 | A1, 1; (I) | |
| Nickel – Elemental, Soluble inorganic compounds, as Ni [7440-02-0] | 0.05 mg/m3 | A1, 1, 2B; (I) | |
| Nickel carbonyl, as Ni [13463-39-3] | 0.001 ppm | 1; (I) | |
| Nickel subsulfide, as Ni, Inhalable [12035-72-2] | 0.1 mg/m3 | A1, 1 | |
| Nicotine [54-11-5] | 0.5 mg/m3 | Skin | |
| Nitrapyrin [1929-82-4] | 10 mg/m3(N) | 20 mg/m3 | |
| Nitric acid [7697-37-2] | 2 ppm | 4 ppm | |
| Nitric oxide [10102-43-9] | 25 ppm | ||
| p-Nitroaniline [100-01-6] | 3 mg/m3 | Skin | |
| Nitrobenzene [98-95-3] | 1 ppm | Skin; 2B | |
| p-Nitrochlorobenzene [100-00-5] | 0.1 ppm | Skin | |
| 4-Nitrodiphenyl [92-93-3] | (L) | Skin; A2 | |
| Nitroethane [79-24-3] | 100 ppm | ||
| Nitrogen [7727-37-9] | Simple asphyxiant | ||
| Nitrogen dioxide [10102-44-0] | C 1 ppm | ||
| Nitrogen trifluoride [7783-54-2] | 10 ppm | ||
| Nitroglycerin (NG) [55-63-0] | 0.05 ppm | Skin | |
| Nitromethane [75-52-5] | 20 ppm | 2B | |
| 1-Nitropropane [108-03-2] | 25 ppm | ||
| 2-Nitropropane [79-46-9] | 5 ppm | 2B | |
| Nitropyrene, mono, di, tri, tetra, isomers [5522-43-0; 57835-92-4] | (I) | ||
| n-Nitrosodiethanolamine [1116-54-7] | 2B | ||
| n-Nitrosodiethylamine [55-18-5] | 2A | ||
| n-Nitrosodimethylamine [62-75-9] | (L) | Skin; 2A | |
| n-Nitrosomethylethylamine [10595-95-6] | 2B | ||
| n-Nitrosomorpholine [59-89-2] | 2B | ||
| n-Nitrosopiperidine [100-75-4] | 2B | ||
| n-Nitrosopyrrolidine [930-55-2] | 2B | ||
| Nitrotoluene, all isomers [88-72-2; 99-08-1; 99-99-0] | 2 ppm | Skin; 2A; (I) | |
| 5-Nitro-o-toluidine, Inhalable [99-55-8] Revised 2007 | 1 mg/m3 | ||
| Nitrous oxide [10024-97-2] | 25 ppm | R | |
| Nonane [111-84-2] Revised 2015 | 200 ppm | ||
| Octachloronaphthalene [2234-13-1] | 0.1 mg/m3 | 0.3 mg/m3 | Skin |
| Octane, all isomers [111-65-9] | 300 ppm | ||
| Oil mist – mineral, mildly refined | 0.2 mg/m3 | 1 | |
| Oil mist – mineral, severely refined | 1 mg/m3 | ||
| Osmium tetroxide [20816-12-0] | 0.0002 ppm | 0.0006 ppm | |
| Oxalic acid, anhydrous [144-62-7] Revised 2015 | 1 mg/m3 | 2 mg/m3 | |
| Oxalic acid, dihydrate [6153-56-6] | (I) | ||
| p,p’-Oxybis(benzenesulfonyl hydrazide), Inhalable [80-51-3] Revised 2008 | 0.1 mg/m3 | R | |
| Oxygen difluoride [7783-41-7] | C 0.05 ppm | ||
| Ozone – Heavy work [10028-15-6] | 0.05 ppm | ||
| Ozone – Moderate work [10028-15-6] | 0.08 ppm | ||
| Ozone – Light work [10028-15-6] | 0.1 ppm | ||
| Ozone – Light, mod., or heavy workload =/< 2 hrs [10028-15-6] | 0.2 ppm | ||
| Paraffin wax fume [8002-74-2] | 2 mg/m3 | ||
| Paraquat, Respirable [4685-14-7] | 0.1 mg/m3 | ||
| Paraquat [4685-14-7] | 0.5 mg/m3 | ||
| Parathion, Inhalable [56-38-2] Revised 2003 | 0.05 mg/m3 (V) | Skin | |
| Particles (Insoluble or Poorly Soluble) Not Otherwise Classified (PNOC) | 10 mg/m3(N) | ||
| Pentaborane [19624-22-7] | 0.005 ppm | 0.015 ppm | |
| Pentachloronaphthalene [1321-64-8] | 0.5 mg/m3 | Skin | |
| Pentachloronitrobenzene [82-68-8] | 0.5 mg/m3 | ||
| Pentachlorophenol [87-86-5] | 0.5 mg/m3 | Skin; 2B | |
| Pentaerythritol [115-77-5] | 10 mg/m3(N) | ||
| Pentane, all isomers [78-78-4; 109-66-0; 463-82-1] | 600 ppm | ||
| 2,4-Pentanedione [123-54-6] | (I) | ||
| Pentyl acetate, all isomers [628-63-7; 626-38-0; 123-92-2; 625-16-1; 624-41-9; 620-11-1] | 50 ppm | 100 ppm | |
| Peracetic acid [79-21-0] | (I) | ||
| Perchloroethylene (See Tetrachloroethylene) | |||
| Perchloromethyl mercaptan [594-42-3] | 0.1 ppm | ||
| Perchloryl fluoride [7616-94-6] | 3 ppm | 6 ppm | |
| Perfluorobutyl ethylene [19430-93-4] Revised 2004 | 100 ppm | ||
| Perfluoroisobutylene [382-21-8] | C 0.01 ppm | ||
| Perlite [93763-70-3] Revised 2006 (See Particles Not Otherwise Classified (PNOC)) | |||
| Persulfates, as persulfate | 0.1 mg/m3 | ||
| Phenol [108-95-2] | 5 ppm | Skin | |
| Phenothiazine [92-84-2] | 5 mg/m3 | Skin | |
| N-Penyl-beta-naphthylamine [135-88-6] | |||
| o-Phenylenediamine [95-54-5] | 0.1 mg/m3 | ||
| m-Phenylenediamine [108-45-2] | 0.1 mg/m3 | ||
| p-Phenylenediamine [106-50-3] | 0.1 mg/m3 | S | |
| Phenyl ether – Vapour (Diphenyl ether) [101-84-8] | 1 ppm | 2 ppm | |
| Phenyl glycidyl ether (PGE) [122-60-1] Revised 2008 | 0.1 ppm | Skin; 2B; S; R | |
| Phenyl isocyanate [103-71-9] | 0.005 ppm | C 0.01 ppm | Skin; S |
| Phenylhydrazine [100-63-0] | 0.1 ppm | Skin | |
| Phenyl mercaptan [108-98-5] | C 0.1 ppm | ||
| Phenylphosphine [638-21-1] | C 0.05 ppm | R | |
| Phorate, Inhalable [298-02-2] Revised 2005 | 0.05 mg/m3 (V) | Skin | |
| Phosgene [75-44-5] | 0.1 ppm | ||
| Phosphine [7803-51-2] | 0.3 ppm | 1 ppm | |
| Phosphoric acid [7664-38-2] | 1 mg/m3 | 3 mg/m3 | |
| Phosphorus (yellow) [12185-10-3] | 0.1 mg/m3 | ||
| Phosphorus oxychloride [10025-87-3] | 0.1 ppm | ||
| Phosphorus pentachloride [10026-13-8] | 0.1 ppm | ||
| Phosphorus pentasulfide [1314-80-3] | 1 mg/m3 | 3 mg/m3 | |
| Phosphorus trichloride [7719-12-2] | 0.2 ppm | 0.5 ppm | |
| Phthalic anhydride [85-44-9] | 1 ppm | S | |
| m-Phthalodinitrile [626-17-5] Revised 2009 | 5 mg/m3(V) | ||
| o-Phthalodinitrile [91-15-6] | (I) | ||
| Picloram [1918-02-1] | 10 mg/m3(N) | ||
| Picric acid [88-89-1] | 0.1 mg/m3 | S | |
| Pindone [83-26-1] | 0.1 mg/m3 | ||
| Piperazine and its Salts, as Piperazine [110-85-0] | 0.3 mg/m3 | 1 mg/m3 | S |
| Piperidine [110-89-4] | 1 ppm | ||
| Plaster of Paris [26499-65-0] | 10 mg/m3(N) | 20 mg/m3 | |
| Platinum – Metal [7440-06-4] | 1 mg/m3 | ||
| Platinum – Soluble salts (as Pt) [7440-06-4] | 0.002 mg/m3 | S | |
| Polyvinyl chloride (PVC), Respirable [9002-86-2] Revised 2008 | 1 mg/m3 | ||
| Portland cement, Respirable [65997-15-1] Revised 2015 | 1 mg/m3(E) | ||
| Potassium hydroxide [1310-58-3] | C 2 mg/m3 | ||
| Propane [74-98-6] Revised 2004 See Aliphatic Hydrocarbon gases [C1-C4] Revised 2008 | |||
| Propane sultone [1120-71-4] | (L) | 2B | |
| n-Propanol (n-Propyl alcohol) [71-23-8] Revised 2007 | 100 ppm | ||
| Propargyl alcohol [107-19-7] | 1 ppm | Skin | |
| beta-Propiolactone [57-57-8] | 0.5 ppm | 2B | |
| Propionaldehyde [123-38-6] | 20 ppm | ||
| Propionic acid [79-09-4] | 10 ppm | ||
| Propoxur [114-26-1] | 0.5 mg/m3 | ||
| n-Propyl acetate [109-60-4] | 200 ppm | 250 ppm | |
| Propylene [115-07-1] Revised 2006 | 500 ppm | ||
| Propylene dichloride [78-87-5] Revised 2006 | 75 ppm | 110 ppm | S |
| Propylene glycol dinitrate [6423-43-4] | 0.05 ppm | Skin | |
| Propylene oxide [75-56-9] | 2 ppm | 2B; S | |
| Propyleneimine [75-55-8] Revised 2009; 2010 | 2 ppm | 2B | |
| n-Propyl nitrate [627-13-4] | 25 ppm | 40 ppm | |
| Pyrethrum [8003-34-7] | 5 mg/m3 | S | |
| Pyridine [110-86-1] Revised 2004 | 1 ppm | ||
| Quinone [106-51-4] | 0.1 ppm | ||
| Resorcinol [108-46-3] | 10 ppm | 20 ppm | |
| Rhodium, Metal and insoluble compounds as Rh [7440-16-6] | 0.1 mg/m3 | 0.3 mg/m3 | |
| Rhodium – Soluble compounds, as Rh [7440-16-6] | 0.001 mg/m3 | 0.003 mg/m3 | |
| Ronnel, Inhalable [299-84-3] Revised 2006 | 5 mg/m3(V) | ||
| Rosin core solder thermal decomposition products (colophony) [8050-09-7] | (L) | S | |
| Rotenone (commercial) [83-79-4] | 5 mg/m3 | ||
| Rouge [1309-37-1] | 10 mg/m3(E,N) | ||
| Rubber solvent (Naphtha) [8030-30-6] Revised 2009 | (H) | ||
| Selenium and compounds, as Se [7782-49-2] | 0.1 mg/m3 | ||
| Selenium hexafluoride [7783-79-1] | 0.05 ppm | ||
| Sesone [136-78-7] | 10 mg/m3(N) | ||
| Silica, Amorphous – Diatomaceous earth (uncalcined) Total [61790-53-2] | 4 mg/m3 | ||
| Silica, Amorphous – Diatomaceous earth (uncalcined), Respirable [61790-53-2] | 1.5 mg/m3 | ||
| Silica, Amorphous – Fume Total [69012-64-2] | 4 mg/m3 | ||
| Silica, Amorphous – Fume, Respirable [69012-64-2] | 1.5 mg/m3 | ||
| Silica, Amorphous – Precipitated and gel, Total [112926-00-8] | 4 mg/m3 | ||
| Silica, Amorphous – Precipitated and gel, Respirable [112926-00-8] | 1.5 mg/m3 | ||
| Silica, Crystalline – alpha quartz [14808-60-7; 1317-95-9] and Cristobalite, Respirable [14464-46-1] Revised 2006 | 0.025 mg/m3 | A2, 1 | |
| Silicon [7440-21-3] Revised 2006 (See Particles Not Otherwise Classified (PNOC)) | |||
| Silicon carbide Nonfibrous, Inhalable, [409-21-2] Revised 2003 | 10 mg/m3(E) | ||
| Silicon carbide, Nonfibrous, Respirable, [409-21-2] Revised 2003 | 3 mg/m3(E) | ||
| Silicon carbide, Fibrous (including whiskers) [409-21-2] Revised 2003 | 0.1 f/cc (F) | A2 | |
| Silicon tetrahydride (Silane) [7803-62-5] | 0.5 ppm | 1 ppm | |
| Silver and Compounds (as Ag) [7440-22-4] | 0.01 mg/m3 | 0.03 mg/m3 | |
| Soapstone (see Talc) Revised 2011 | |||
| Sodium azide (as Sodium azide) [26628-22-8] | C 0.29 mg/m3 | ||
| Sodium azide (as Hydrazoic acid vapour) [26628-22-8] | C 0.11 ppm | ||
| Sodium bisulfite [7631-90-5] | 5 mg/m3 | ||
| Sodium fluoroacetate [62-74-8] | 0.05 mg/m3 | Skin | |
| Sodium hydroxide [1310-73-2] | C 2 mg/m3 | ||
| Sodium metabisulfite [7681-57-4] | 5 mg/m3 | ||
| Starch [9005-25-8] | 10 mg/m3(N) | ||
| Stearates | 10 mg/m3(J) | ||
| Stoddard solvent (mineral spirits) [8052-41-3] | 290 mg/m3 | 580 mg/m3 | |
| Strontium chromate, as Cr [7789-06-2] | 0.0005 mg/m3 | A2 | |
| Strychnine [57-24-9] | 0.15 mg/m3 | ||
| Styrene – monomer [100-42-5] | 50 ppm | 75 ppm | 2B |
| Subtilisins, as crystalline active enzyme [1395-21-7; 9014-01-1] | C 0.00006 mg/m3 | S | |
| Sucrose [57-50-1] | 10 mg/m3(N) | ||
| Sulfometuron methyl [74222-97-2] | 5 mg/m3 | ||
| Sulfotepp (TEDP), Inhalable [3689-24-5] Revised 2005 | 0.1 mg/m3(V) | Skin | |
| Sulfur dioxide [7446-09-5] | 2 ppm | 5 ppm | |
| Sulfur hexafluoride [2551-62-4] | 1000 ppm | ||
| Sulfuric acid, Thoracic [7664-93-9] Revised 2004 | 0.2 mg/m3(M) | A2, 1 | |
| Sulfur monochloride [10025-67-9] | C 1ppm | ||
| Sulfur pentafluoride [5714-22-7] | C 0.01 ppm | ||
| Sulfur tetrafluoride [7783-60-0] | C 0.1 ppm | ||
| Sulfuryl fluoride [2699-79-8] | 5 ppm | 10 ppm | |
| Sulprofos [35400-43-2] Revised 2009; 2010 | 1 mg/m3 | Skin | |
| Synthetic Vitreous Fibres – Continuous filament glass fibres | 1 f/cc (F) | ||
| Synthetic Vitreous Fibres – Continuous filament glass fibres, Inhalable | 5 mg/m3 | ||
| Synthetic Vitreous Fibres – Glass wool fibres | 1 f/cc (F) | ||
| Synthetic Vitreous Fibres – Rock wool fibres | 1 f/cc (F) | ||
| Synthetic Vitreous Fibres -Slag wool fibres | 1 f/cc (F) | ||
| Synthetic Vitreous Fibres – Special purpose glass fibres | 1 f/cc (F) | 2B | |
| Synthetic Vitreous Fibres – Refractory ceramic fibres | 0.2 f/cc (F) | A2, 2B | |
| 2,4,5-T (2,4,5-Trichlorophenoxyacetic acid) [93-76-5] | 10 mg/m3 | ||
| Talc – Containing no asbestos fibres, Respirable [14807-96-6] | 2 mg/m3(E) | ||
| Talc – Containing asbestos fibres [14807-96-6] | 0.1 f/cc (K) | A1, 1 | |
| Tantalum – Metal [7440-25-7] | 5 mg/m3 | ||
| Tantalum oxide dusts, as Ta [1314-61-0] | 5 mg/m3 | ||
| Tellurium and compounds (NOS), as Te, excluding hydrogen telluride [13494-80-9] | 0.1 mg/m3 | ||
| Tellurium hexafluoride [7783-80-4] | 0.02 ppm | ||
| Temephos, Inhalable [3383-96-8] Revised 2005 | 1 mg/m3(V) | Skin | |
| Terbufos, Inhalable [13071-79-9] | 0.01 mg/m3 (V) | Skin | |
| Terepthalic acid [100-21-0] | 10 mg/m3(N) | ||
| Terphenyls [26140-60-3] | C 5 mg/m3 | ||
| 1,1,2,2-Tetrabromoethane, Inhalable [79-27-6] Revised 2006 | 0.1 ppm (V) | ||
| 1,1,1,2-Tetrachloro-2,2-difluoroethane [76-11-9] Revised 2008; 2010 | 500 ppm | ||
| 1,1,2,2-Tetrachloro-1,2-difluoroethane [76-12-0] Revised 2008; 2010 | 200 ppm | ||
| 1,1,2,2-Tetrachloroethane [79-34-5] | 1 ppm | Skin; 2B | |
| Tetrachloroethylene (Perchloroethylene) [127-18-4] | 25 ppm | 100 ppm | 2A |
| Tetrachloronaphthalene [1335-88-2] | 2 mg/m3 | ||
| Tetraethyl lead, as Pb [78-00-2] | 0.075 mg/m3 | Skin | |
| Tetraethyl pyrophosphate (TEPP), Inhalable [107-49-3] Revised 2007 | 0.01 mg/m (V) | Skin | |
| Tetrafluoroethylene [116-14-3] | 2 ppm | 2B | |
| Tetrahydrofuran [109-99-9] Revised 2005 | 50 ppm | 100 ppm | Skin |
| Tetramethyl lead, as Pb [75-74-1] | 0.075 mg/m3 | Skin | |
| Tetramethyl succinonitrile [3333-52-6] | 0.5 ppm | Skin | |
| Tetranitromethane [509-14-8] | 0.005 ppm | 2B | |
| Tetrakis (hydroxymethyl) phosphonium chloride [124-64-1] Revised 2005 | 2 mg/m3 | ||
| Tetrakis (hydroxymethyl) phosphonium sulfate [55566-30-8] Revised 2005 | 2 mg/m3 | S | |
| Tetryl [479-45-8] | 1.5 mg/m3 | S | |
| Thallium and soluble compounds, as Tl, Inhalable [7440-28-0] Revised 2011 | 0.02 mg/m3 | Skin | |
| 4,4′-Thiobis (6-tert-butyl-m-cresol) Inhalable [96-69-5] Revised 2011 | 1 mg/m3 | Skin | |
| Thioglycolic acid [68-11-1] | 1 ppm | Skin | |
| Thionyl chloride [7719-09-7] | C 1ppm | ||
| Thiram [137-26-8] Revised 2008; 2010 | 1 mg/m3 | S | |
| Tin – Metal [7440-31-5] | 2 mg/m3 | ||
| Tin – Oxide and inorganic compounds, except tin hydride, as Sn [7440-31-6] | 2 mg/m3 | ||
| Tin – Organic compounds, as Sn [7440-31-6] | 0.1 mg/m3 | 0.2 mg/m3 | Skin |
| Titanium dioxide [13463-67-7] Revised 2006 | 10 mg/m3(N) | 2B | |
| o-Tolidine [119-93-7] | Skin; 2B | ||
| Toluene [108-88-3] Revised 2007; 2008 | 20 ppm | R | |
| Toluene-2,4-diisocyanate (2,4-TDI) [584-84-9] | 0.005 ppm | C 0.01 ppm | 2B; S |
| Toluene-2,6-diisocyanate (2,6-TDI) [91-08-7] | 0.005 ppm | C 0.01 ppm | 2B; S |
| o-Toluidine [95-53-4] Revised 2009 | 2 ppm | Skin; 1 | |
| m-Toluidine [108-44-1] | 2 ppm | Skin | |
| p-Toluidine [106-49-0] | 2 ppm | Skin | |
| Tributyl phosphate [126-73-8] | 0.2 ppm | ||
| Trichloroacetic acid [76-03-9] | 1 ppm | 2B | |
| 1,2,4-Trichlorobenzene [120-82-1] | C 5 ppm | ||
| 1,1,2-Trichloroethane [79-00-5] | 10 ppm | Skin | |
| Trichloroethylene [79-01-6] Revised 2007 | 10 ppm | 25 ppm | A2, 1 |
| Trichlorofluoromethane [75-69-4] | C 1000 ppm | ||
| Trichloronaphthalene [1321-65-9] | 5 mg/m3 | Skin | |
| 1,2,3-Trichloropropane [96-18-4] | 10 ppm | Skin; A2, 2A | |
| 1,1,2-Trichloro-1,2,2-trifluoroethane [76-13-1] | 500 ppm | 1250 ppm | |
| Trichlorphon, Inhalable [52-68-6] Revised 2003 | 1 mg/m3 | ||
| Triethanolamine [102-71-6] | 5 mg/m3 | ||
| Triethylamine [121-44-8] | 1 ppm | 3 ppm | Skin |
| Trifluorobromomethane [75-63-8] | 1000 ppm | ||
| 1,3,5-Triglycidyl-s-triazinetrione [2451-62-9] | 0.05 mg/m3 | R; S | |
| Trimellitic anhydride [552-30-7] Revised 2008; 2010 | C 0.04 mg/m3 | Skin; S | |
| Trimethylamine [75-50-3] | 5 ppm | 15 ppm | |
| Trimethyl benzene (mixed isomers) [25551-13-7] | 25 ppm | ||
| Trimethyl hexamethylene diisocyanate [28679-16-5] | 0.005 ppm | C 0.01 ppm | |
| Trimethyl phosphite [121-45-9] | 2 ppm | ||
| Tri-n-Butyltin compounds [688-73-3] | 0.05 mg/m3 | ||
| 2,4,6-Trinitrotoluene (TNT) [118-96-7] | 0.1 mg/m3 | Skin | |
| Triorthocresyl phosphate [78-30-8] | 0.1 mg/m3 | Skin | |
| Triphenyl phosphate [115-86-6] | 3 mg/m3 | ||
| Tungsten – Metal and insoluble compounds [7440-33-7] | 5 mg/m3 | 10 mg/m3 | |
| Tungsten – Soluble compounds, as W [7440-33-7] | 1 mg/m3 | 3 mg/m3 | |
| Turpentine [8006-64-2] and selected monoterpenes [80-56-8; 127-91-3; 13466-78-9] Revised 2003 | 20 ppm | S | |
| Uranium (Natural) – Insoluble compounds, as U [7440-61-1] | 0.2 mg/m3 | 0.6 mg/m3 | A1, 1; (I) |
| Uranium (Natural) – Soluble compounds, as U [7440-61-1] | 0.05 mg/m3 | A1, 1; (I) | |
| n-Valeraldehyde [110-62-3] | 50 ppm | ||
| Vanadium pentoxide, as V, Inhalable [1314-62-1] Revised 2015 | 0.05 mg/m3 | 2B | |
| Vegetable oil – Mist, except castor, cashew nut, or similar irritant oils [8008-89-7] | 10 mg/m3 | ||
| Vegetable oil, Mist, Respirable, except castor, cashew nut, or similar irritating oil [8008-89-7] | 3 mg/m3 | ||
| Vinyl acetate [108-05-4] | 10 ppm | 15 ppm | 2B |
| Vinyl bromide [593-60-2] | 0.5 ppm | A2, 2A | |
| Vinyl chloride [75-01-4] | 1 ppm | A1, 1 | |
| 4-Vinyl cyclohexene [100-40-3] | 0.1 ppm | 2B; R | |
| Vinyl cyclohexene dioxide [106-87-6] | 0.1 ppm | Skin; 2B; R | |
| Vinyl fluoride [75-02-5] | 1 ppm | A2, 2A | |
| N-Vinyl-2-pyrrolidone [88-12-0] Revised 2003 | 0.05 ppm | ||
| Vinylidene chloride [75-35-4] | 1 ppm | ||
| Vinylidene fluoride [75-38-7] | 500 ppm | ||
| Vinyl toluene, all isomers [25013-15-4] | 25 ppm | 75 ppm | |
| VM & P Naphtha [8032-32-4] Revised 2009 | (H) | ||
| Warfarin [81-81-2] | 0.1 mg/m3 | ||
| Wood dust – Allergenic species | 1 mg/m3 | A1, A2, 1; (I) | |
| Wood dust – Non-Allergenic Hardwood | 1 mg/m3 | A1, A2, 1; (I) | |
| Wood dust – Non-Allergenic Softwood | 2.5 mg/m3 | 1 | |
| Xylene [1330-20-7] (o, m & p isomers) [95-47-6; 108-38-3; 106-42-3] | 100 ppm | 150 ppm | |
| m-Xylene alpha,alpha’-diamine [1477-55-0] | C 0.1 mg/m3 | Skin | |
| Xylidine – Mixed isomers, Inhalable [1330-73-8] | 0.5 ppm (V) | Skin | |
| Yttrium – Metal [7440-65-5] | 1 mg/m3 | ||
| Yttrium and compounds, as Y [7440-65-5] | 1 mg/m3 | ||
| Zinc chloride – Fume [7646-85-7] | 1 mg/m3 | 2 mg/m3 | |
| Zinc chromates, as Cr [13530-65-9; 11103-86-9; 37300-23-5] | 0.01 mg/m3 | A1, 1; (I) | |
| Zinc oxide, Respirable [1314-13-2] Revised 2003 | 2 mg/m3 | 10 mg/m3 | |
| Zinc stearate [557-05-1] | 10 mg/m3(N) | 20 mg/m3 | |
| Zirconium [7440-67-7] and compounds, as Zr [7440-67-7] | 5 mg/m3 | 10 mg/m3 |
Endnotes
1, 2A and 2B indicate substances designated as carcinogens
(C) – Ceiling limit.
(E) – the value is for particulate matter containing no asbestos and less than 1% crystalline silica.
(F) – the value for fibers longer than 5 microns, with an aspect ratio of equal than/greater than 3:1, as determined by the membrane filter method at 400 – 450 times magnification (4 mm objective), using phase-contrast illumination.
(G) – as measured by the vertical elutriator, cotton-dust sampler, see TLV Documentation.
(H) – reciprocal calculation method based on OHS Guideline G5.48-12.
(I) – see Special Notes
(J) – does not include stearates of toxic metals.
(K) – should not exceed 2 mg/m3 respirable particulate.
(L) – No exposure limit. Exposure by all routes should be carefully controlled to levels as low as possible.
(M) – refers to sulfuric acid contained in strong inorganic acid mists.
(N) – the 8-hour TWA listed in the Table is for the total dust. The substance also has an 8-hour TWA of 3 mg/m3 for the respirable fraction.
(O) – sampled by method that does not collect vapour.
(P) – application restricted to conditions in which there are negligible aerosol exposures.
(R) – substance has an adverse reproductive effect.
(S) – indicates that the substance is a sensitizer.
(V) – vapour and inhalable aerosol.
