Government of India
THE SECOND SCHEDULE
(See Section 41-F)
Permissible Levels of Certain Chemical substances in work environment
Sl. No. | Substances | Permissible Limits of Exposure | |||
|---|---|---|---|---|---|
Time-Weighted Average- Concentration (TWA) (8 hrs.) | Short-term exposure Limit STEL (15 min) | ||||
ppm | mg/m3** | ppm | mg/m3** | ||
1 | 2 | 3 | 4 | 5 | 6 |
1 | Acetaldehyde | 100 | 180 | 150 | 270 |
2 | Acetic acid | 10 | 25 | 15 | 37 |
3 | Acetone | 750 | 1,780 | 1,000 | 2,375 |
4 | Acrolein | 0.1 | 0.25 | 0.3 | 0.8 |
5. | Acrylonitrile-Skin(S.C) | 2 | 4.5 | -- | -- |
6. | Aldrin-Skin | -- | 0.25 | -- | -- |
7 | Allyl Chloride | 1 | 3 | 2 | 6 |
8. | Ammonia | 25 | 18 | 35 | 27 |
9. | Aniline-Skin | 2 | 10 | -- | -- |
10 | Anisidine (o, p-isomers)-Skin | 0.1 | 0.5 | -- | -- |
11 | Arsenic & soluble compounds (as As) | -- | 0.2 | -- | -- |
2[12 | Benzene (H.C.) | 0.5 | 1.5 | 2.5 | 7.5] |
13 | Beryllium & compounds (as Be (S.C.) | -- | 0.002 | -- | -- |
14 | Boron trifluoride-C | 1 | 3 | -- | -- |
15 | Bromine | 0.1 | 0.7 | 0.3 | 2 |
16 | Butane | 800 | 1,900 | -- | -- |
17 | 2-Butanone (Metyl ethyl Ketone-MEK) | 200 | 590 | 300 | 885 |
18 | n-Butyl acetate | 150 | 710 | 200 | 950 |
19 | n-Butyl alcohol-Skin-C | 50 | 150 | -- | -- |
20 | Sec/Tert. Butyl acetate | 200 | 950 | -- | -- |
21 | Butyl mercaptan | 0.5 | 1.5 | -- | -- |
22 | Cadmium Dusts and Salts (as Cd) | -- | 0.05 | -- | -- |
23 | Calcium Oxide | -- | 2 | -- | -- |
24 | Carbaryl (Sevin) | -- | 5 | -- | -- |
25 | Carbofuran (Furadan) | -- | 0.1 | -- | -- |
26 | Carbon disulphide –Skin | 10 | 30 | -- | -- |
27 | Carbon Monoxide | 50 | 55 | 400 | 440 |
28 | Carbon Tetrachloride Skin (S.C.) | 5 | 30 | -- | -- |
29 | Chlordane –Skin | -- | 0.5 | -- | 2 |
30 | Chlorine | 1 | 3 | 3 | 9 |
1. Ins. by Act 20 of 1987, S.45 (w.e.f. 1.12.1987)
2. Subs. by S.O.342(E) dt.19.4.2001(w.e.f.) 19.4.2001, Gaz. of India Ext.247, dt. 19.4.2001. Pt.II, Sec.3(ii).
31 | Chlorobenzene (Monochlorobenzene) | 75 | 350 | -- | -- |
32 | Chloroform (S.C.) | 10 | 50 | -- | -- |
33 | bis (Chloromethyl) ether (H.C.) | 0.001 | 0.005 | -- | -- |
34 | Chromic acid and chromates (as Cr) (Water soluble) | -- | 0.05 | -- | -- |
35 | Chrombus salts (as Cr) | -- | 0.5 | -- | -- |
36 | Copper Fume | -- | 0.2 | -- | -- |
37 | Cotton Dust, raw | -- | 0.2 *1 | -- | -- |
38 | Cresol, all isomers-Skin | 5 | 22 | -- | -- |
39 | Cyanide (as CN)-Skin | -- | 5 | -- | -- |
40 | Cyanogen | 10 | 20 | -- | -- |
41 | DDT (Dichlorodiphenyl trichlorothane) | -- | 1 | -- | -- |
42 | Demeton-Skin | 0.01 | 0.1 | -- | -- |
43 | Diazinon-Skin | -- | 0.1 | -- | -- |
44 | Dibutyl phthalate | -- | 5 | -- | -- |
45 | Dichlorvos (DDVP)-Skin | 0.1 | 1 | -- | -- |
46 | Dieldrin-Skin | 0.25 | -- | -- | -- |
47 | Dinitrobenzene (all isomers)-Skin | 0.15 | 1 | -- | -- |
48 | Dinitrotoluene-Skin | -- | 1.5 | -- | -- |
49 | Diphenyl (Biphenyl) | 0.2 | 1.5 | -- | -- |
50 | Endosulfan (Thiodan)-Skin | -- | 0.1 | -- | -- |
51 | Endrin-Skin | -- | 0.1 | -- | -- |
52 | Ethylacetate | 400 | 1,400 | -- | -- |
53 | Enthyl alcohol | 1,000 | 1,900 | -- | -- |
54 | Ethylamine | 10 | 18 | -- | -- |
55 | Fluoride (as F) | -- | 2.5 | -- | -- |
56 | Fluorine | 1 | 2 | 2 | 4 |
57 | Formaldehyde (S.C.) | 1.0 | 1.5 | 2 | 3 |
58 | Formic acid | 5 | 9 | -- | -- |
59 | Gasoline | 300 | 900 | 500 | 1,500 |
60 | Hydrazine-skin (S.C.) | 0.1 | 0.1 | -- | -- |
61 | Hydrogen chloride-C | 5 | 7 | -- | -- |
62 | Hydrogen cyanide-Skin-C | 10 | 10 | -- | -- |
63 | Hydrogen fluoride(as F)-C | 3 | 2.5 | -- | -- |
64 | Hydrogen peroxide | 1 | 1.5 | -- | -- |
65 | Hydrogen Sulphide | 10 | 14 | 15 | 21 |
66 | Iodine-C | 0.1 | 1 | -- | -- |
67 | Iron Oxide Fume (Fe2 O3 (as Fe) | -- | 5 | -- | -- |
68 | Isoamyl acetate | 100 | 525 | -- | -- |
1 *Lint-free dust as measured by the vertical elutricator cotton dust sampler.
1 | 2 | 3 | 4 | 5 | 6 |
|---|---|---|---|---|---|
69 | Isoamyl Alcohol | 100 | 360 | 125 | 450 |
70 | Isobutyl alcohol | 50 | 150 | -- | -- |
71 | Lead, inorg, dusts and fumes (as Pb) | -- | 0.15 | -- | -- |
72 | Lindane-Skin | -- | 0.5 | -- | -- |
73 | Malathion-Skin | -- | 10 | -- | -- |
74 | Manganese dust and compounds (as Mn)-C | -- | 5 | -- | -- |
75 | Manganese fume (as Mn) | -- | 1 | -- | 0.03 |
76 | Mercury (as Hg)-Skin |
|
|
|
|
(i) Alkyl compounds | -- | 0.01 | -- | 0.03 | |
(ii) All forms except alkyl vapour | -- | 0.05 | -- | -- | |
(iii) Aryl and inorganic compounds | -- | 0.1 | -- | -- | |
77 | Methyl alcohol (Methanol)- Skin | 200 | 260 | 250 | 310 |
78 | Methyl cellosolve (2-Methoxyethanol)-Skin | 5 | 16 | -- | -- |
79 | Methyl isobutyl ketone | 50 | 205 | 75 | 300 |
80 | Methyl isocyanate-Skin | 0.02 | 0.05 | -- | -- |
81 | Naphthalene | 10 | 50 | 15 | 75 |
82 | Nickel carbonyl (as Ni) | 0.05 | 0.35 | -- | -- |
83 | Nitric acid | 2 | 5 | 4 | 10 |
84 | Nitric oxide | 25 | 30 | -- | -- |
85 | Nitrobenzene-Skin | 1 | 5 | -- | -- |
86 | Nitrogen dioxide | 3 | 6 | 5 | 10 |
87 | Oil mist mineral | -- | 5 | -- | 10 |
88 | Ozone | 0.1 | 0.2 | 0.3 | 0.6 |
89 | Parathion-Skin | -- | 0.1 | -- | -- |
90 | Phenol-Skin | 5 | 19 | -- | -- |
91 | Phorate (Thimet)-Skin-- | -- | 0.05 | -- | 0.2 |
92 | Phosgene (Carbonyl chloride) | 0.1 | 0.4 | -- | -- |
93 | Phosphine | 0.3 | 0.4 | 1 | 1 |
94 | Phosphoric acid (yellow) | -- | 1 | -- | 3 |
95 | Phosphorus (yellow) | -- | 0.1 | -- | -- |
96 | Phosphorus pentachloride | 0.1 | 1 | -- | -- |
97 | Phosphorus trichloride | 0.2 | 1.5 | 0.5 | 3 |
98 | Picric acid-Skin | -- | 0.1 | -- | 0.3 |
99 | Pyridine | 5 | 15 | -- | -- |
100 | Silane (Silicon tetrahydride | 5 | 7 | -- | -- |
101 | Sodium hydroxide C | -- | 2 | -- | -- |
102 | Styrene, monomer (Phenylethylene) | 50 | 215 | 100 | 425 |
103 | Sulphur dioxide | 2 | 5 | 5 | 10 |
104 | Sulphur hexafluoride | 1,000 | 6,000 | -- | -- |
105 | Sulphuric Acid | -- | 1 | -- | -- |
106 | Tetraethyl lead (as Pb)-Skin | -- | 0.1 | -- | -- |
107 | Toluene (Toluol) | 100 | 375 | 150 | 560 |
108 | O-Tuluidine-Skin (S.C) | 2 | 9 | -- | -- |
109 | Tributyl Phosphate | 0.2 | 2.5 | -- | -- |
110 | Trichloroethylene | 50 | 270 | 200 | 1,080 |
111 | Uranium, natural (as U) | -- | 0.2 | -- | 0.6 |
112 | Vinyl chloride (H.C.) | 5 | 10 | -- | -- |
113 | Welding fumes | -- | 5 | -- | -- |
114 | Xylene (o-,m-, p-isomers | 100 | 435 | 150 | 655 |
115 | Zinc oxide |
|
|
|
|
(i) Fume | -- | 5.0 | -- | 10 | |
(ii)Dust (Total dust) | -- | 10.00 | -- | -- | |
116 | Zirconium compounds (as Zr) | -- | 5 | -- | 10 |
ppm : | Parts of vapour or gas per million parts of contaminated air by volume at 25OC and 760 toor (mm of mercury) |
mg/m3 | milligram of substances per cubic metre of air. |
*: ,. | Not more than 4 times a day with at least 60 min. internal between successive exposures |
**: | Molecular weight mg/m3 ----------------------------------x ppm 24.45 |
C : | denotes ceiling limit. |
Skin : | denotes potential contribution to the overall exposure by the cutaneous route including mucous membranes and eye. |
S.C. : | denotes suspected human carcinogens. |
H.C. : | denotes confirmed human carcinogens. |
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Substance Permissible time-weighted average concentration
(TWA) (8 hours)
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Silica, Si O2
(a) Crystalline
(i) Quartz
10600
(1) In terms of dust count ------------------------------------- mppcm
% Quartz + 10
10
(2)
In terms of respirable dust --------------------------------- mg/m3
% respirable Quartz + 2
30
(3) In terms of total dust -------------------------------------- mg/m3
% Quartz + 3
(ii) Cristobalite : Half the limits given against quartz
(iii) Tridymite : Half the limits given against quartz
(iv) Silica, fused : Same limits as for quartz
(v) Tripoli : Same limit as in formula in item (2) given
against quartz
(b) Amorphous Silicates : 10 mg/m3, Total Dust
[Asbestos (H.C.
(a) Amosite ………………………………0.5 fibre/cc***
(b) Chrystolite …………………………….1.0 fibre/cc***
(c) Crocidolite ……………………………..0.2 fibre/cc***]
Portland cement : 10 mg/m3, Total dust containing less than 1% quartz.
Coal Dust : 2mg/m3, respirable dust fraction containing less than
5% quartz.
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mppcm : Million particles per cubic metre of air, based on impinger samples counted by light field techniques.
*** (i) For fibres greater than 5 um in length and less than 5 um in breadth with length to breadth ratio equal to or greater than 3:1.
(ii) As determined by the membrane filter method at 400-450 x magnification (4mm objective) phase contrast illumination.
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Respirable Dust :
Fraction passing a size-selector with the following characteristics :
Aerodynamic Diameter (UM) (Unit density sphere) | % passing selector |
|---|---|
2 | 90 |
2.5 | 75 |
3.5 | 50 |
5.0 | 25 |
10 | 0 |
2. Subs. by S.O.342(E) dt.19.4.2001(w.e.f.) 19.4.2001, Gaz. of India Ext.247, dt. 19.4.2001. Pt.II, Sec.3(ii).
Date: 4th June, 2007
