Schedule to Schedule XXXVII

1. Definitions: for the purpose of this schedule -

(a) "mg/m3" means milligrams of a substances per cubic metre of air;

(b) "mppem" means million particles of a substance per cubic metre of air;

(r:) "ppm" means parts of vapour or gas per million parts of air by volume at 25 degrees

centigrade and 760 mm of mercury pressure;

(d) "Time weighted average concentration" means the average concentration of a substance

in the air at any work location in a factory computed from evaluation of adequate number of

air samples taken at that location, spread over the entire shift on any day, after giving weightage

to the duration for which each such sample is collected and the concentration prevailing at the

time of taking the sample.

Time weighted average C1T1 + C2T2 + CnTn

Concentration = T1 + T2 +. Tn

Where C1 represents the concentration of the substance for duration T1 (in hours);

C2 represents the concentration of the substance for duration T2 (in hours); and Cn represents

the concentration of the substance for duration Tn (in hours).

(e) "Work location" means a location in a factory at which a worker works or may be

required to work at any time during any shift on any day.

2. Limits of concentration of substances at work location: - (1) The time weighted average

concentration of any substance listed in table 1 or 2 of the schedule, at any work location in a

factory during any shift on any day shall not exceed the limit of the permissible time weighted

average concentration specified in respect of that substance:

Provided that in the case of a substance mentioned in Table 1 in respect of which a limit in

terms of short-term maximum concentration is indicated, the concentration of such a substance

may exceed the permissible limit of the time weighted average concentration for the substance

for short periods not exceeding 15 minutes at a time, subject to the condition that-

(a) Such periods during which the concentration exceeds the prescribed timeweighted average

concentration are restricted to not more than 4 per shift;

(b) the time interval between any two such periods of higher exposure shall not be less than

60 minutes; and

(c) At no time the concentration of the substance in the air shall exceed the limit of short-

term maximum concentration.

(2) In the case of any substance given in Table 3, the concentration of the substance at any

work location in a factory at any time during any day shall not exceed the limit of exposure for

that substance specified in the table.

(3) In the cases where the word "skin" has been indicated against certain substance

mentioned in Tables 1 and 3, appropriate measures shall be taken to prevent absorption through

cutaneous routes particularly skin, mucous membranes, and eyes as the limits specified in these

Tables are for conditions where the exposure is only through respiratory tract.

(4) (a) In case, the air at any work location contains a mixture of such substances mentioned

in Table 1, 2 or 3, which have similar toxic properties, the time weighted concentration of each

of these substances during the shift should be such that when these time weighted concentration

divided by the respective permissible time weighted average concentration specified in the

above mentioned tables, and the fractions obtained are added together, the total shall not exceed

unity.

C1 C2 Cn

-----+-----+-----+ L1 L2 Ln

Where C1, C2. Cn are the time weighted concentration of toxic substances 1, 2, and n

respectively, determined after measurement at work location; And L1, L2 Ln are the

permissible time weighted average concentration of the toxic substances 1, 2, and n

respectively.

(b) ln case the air at any work location contains a mixture of substances, mentioned in Table

1, 2, 3 and these do not have similar toxic properties, then the time weighted concentration of

each of these substances shall not exceed the permissible time weighted average concentration

specified in the above-mentioned tables, for that particular substance.

(c) The requirement in clauses (a) and (b) shall be in addition to the requirements in

paragraphs 2 (1) and 2(2).

3. Power to require assessment of concentration of substances. -

(1) An Inspector-cum-Facilitator may, by an order in writing, direct the occupier or manager of

a factory to get before any specified date, the assessment of the time weighted average

concentration at any work location of any of the substances mentioned in Table 1,2 or 3 carried

out.

(2) The results of such assessment as well as the method followed for air sampling and analysis

for such assessment shall be sent to the Inspector-cum-Facilitator within 3 days from the date

of completion of such assessment and also a record of the same kept readily available for

inspection by an Inspector-cum-Facilitator.

4. Exemption.- If in respect of any factory or a part of a factory, the Inspector-cum-

Facilitator is satisfied that, by virtue of the pattern of working time of the workers at different

work locations or an account of other circumstances, no worker is exposed, in the air at the

work locations, to a substance or substances specified in Tables 1,2 or 3 to such an extent as is

likely to be injurious to his health, he (the Chief Inspector-cum-Facilitator) may by an order in

writing, exempt the factory or a part of the factory from the requirements in paragraph 2, subject

to such conditions, if any, as he may specify therein.

Table -1

Substance Permissible level of exposure

Time-weighted average Short-term maximum

concentration concentration

+ p p m Mg/m3 p p m mg/m3

Acetic acid 1 25 1 37

0 5

Acrolein 0 0.2 0 0.8

1 5 3

Aldrin-skin - 0.5 _ 0.7

8 5

Ammonia 2 18 3 27

5 5

Aniline-skin 2 10 5 20

Anisidine (o- 1 0.5 - -

pisomera)-skin 1

Arsenic and - 0.2 - -

compounds

Benzene 1 30 - -

0

Bromine 0 0.7 0 2

1 3

2- 2 59 3 88

Butanone(methylethyl) 0 0 0 5

(ketone-mek) 0 0

n-Buty la cetate 1 71 2 95

5 0 0 0

0 0

Secondary/Tertiary 2 95 2 11

Butyl Acetate 0 0 5 90

0 0

Cadmium dust and salt - 0.0 - 0.2

(as cd) 5

Cacium - 2 - -

Carbyl (sevin) - 5 - 10

Carbofuran (furadan) - 0.1 - -

Carbon disulphide- 2 60 3 90

skin 0

Carbon mono oxide 5 55 4 44

0 0 0

Carbon tetra choloride 1 65 2 13

skin 0 0 0

Carbonyl chloride 0 0.4 - -

(Phosgene) 1

Chlordane-skin - 9.5 - 2

Chlorobenzone 7 35 - -

(MonoChlorobeneze 5 0

Chlorine 1 3 3 9

Bi-Chloromethyl Ether 0 - - -

0

0

1

Chromic Acid and - 0.0 - -

Chromates (as cr) 5

Chrominum sel - 0.0 - -

Chromic, Chrmous 5

salts

Copper Fumes - 0.2 - -

Cotton Dust (raw) - 0.0 - -

2

Cresol, All Isomers - 5 22 - -

skin

Cynides (as cn) skin - 5 - -

Cynanogen 1 20 - -

0

DDT - 1 - 3

(DicholoroDiphenyl

Trichloro-Ethane)

Demton-skin 0 0.1 0 0.3

0 0

1 3

Diazinon-skin - 0.1 - 0.3

Dibutyl phthalate - 5 - 10

Dichlorves (ddv)-skin 0 1 0 3

1 3

Dieldrin-skin - 0.2 - 0.7

5 5

Dinitrotuolene-skin - 1.5 - 5

Diphenyl 0 1.5 0 4

2 6

Endosulfam (thiodan)- - 0.1 - 0.3

skin

Endrin-skin - 0.1 - 0.3

Ethyl acetate 4 10 - -

0 00

0

Ethyl Alcohol 1 19 - -

0 00

0

0

Ethyl amine 6 18 - -

0

Flourides - 2.5 - -

Fluorin 1 2 2 4

Hydrogen cynide-skin 1 11 1 16

0 5

Hydrogen Sulfide 1 15 1 27

0 6

Iron oxide fumes - 5 - 10

Isoamyl acetate 1 52 1 65

0 5 2 5

0 5

Isobutyl alcohol 1 36 1 45

0 0 2 0

0 5

Isobutyl alcohol 5 15 7 22

0 0 5 5

Lead fumes and dust - 0.1 - 0.4

5 5

Libdane-skin - 0.5 - 1.5

Malathion-skin - 10 - -

Manganess fumes - 1 - 1

Mercury - 0.0+5 - 0.1

5

Merury(alkyl 0. 0.0 0 0.0

compounds)s kin 0 1 0 3

0 0

3

Methyl alcohol 2 26 2 31

(methanol)-skin 0 0 5 0

0 0

Methyl celloply skin 2 80 3 12

(2- methoxy ethanol) 5 5 0

Methyl isobutyl 1 41 1 51

ketone-skin 0 0 2 0

0 5

Naphthalene 1 50 1 75

0 5

Nickel carbonyl 0 0.3 - -

0 5

5

Nitric acid 2 5 4 10

Nitric oxide 2 30 3 45

5 5

Nitrobenzene-skin 1 5 2 10

Oil mist minerals - 5 - 10

Parathion-skin - 0.0 - 0.0

1 3

Phenel-skin 5 19 1 38

Phorate (thimet) – skin - 0.0 0.2

5

Phosgene (Carbonyl 0. 0.4 1 1

Chloride) 1

Phosphine 0. 0.4 1 1

3

Phasphorous (yellow) - 0.1 - 0.3

Phasphorous - 1 - 3

pentachloride

Phasphorous 0. 3 - -

tyrichloride 5

Picric acid-skin - 0.1 - 0.3

Pyridine 5 15 1 30

Saline (silicontetrahyd 0. 0.7 1 1.5

ride) 5

Styrene monorner 1 42 1 52

(Phenylethy lene) 0 0 2 5

0 5

Sulfur diodide 5 13 - -

Sulphuric acid - 1 - -

Toludine (toloul)-skin 1 37 1 50

0 5 5 0

0 0

O-Toludine 5 22 1 44

0

Trichloroethylene 1 53 1 80

0 5 5 0

0 0

Vinyl chloride 5 10 - -

Welding fumes - 5 - -

(nitrous oxide)

Xylene (o-m-p- 10 43 1 65

isomers)-skin 0 5 5 5

0

Table -2

S. Substance Permissible time average concentration

No

1 Silica

a Crystalline

I Quartz 1 In term of dustcount = 1060/-

(% quartz +1 0) in mppcm

2. In term of respirabledust = 10/

(% respire blequuartz +2) in

mg/cubic metre

3 In iterm of totaldust = 30/ (%

quartz + 3) in mg/cuhbic metre

ii Cristobalite Half of the limit given against quartz

iii Tridmite DO

iv Silica fused As for quartz

V Tripoli As for item (2) quartz

b Amorphous 705 mppcm

2 Silicate having less than 1% free silica

by weight

a Asbestos fibres longer than 5 2 fibres per cubic centimetres

microns

b Mica 705 mppcm

c Mineral wool fibre 10 mg per cubic metres

d Portlite 1060 mppcm

e Portland Cement 1060 mppcm

f Soapstone 705 mppcm

g Talc (nonbost) -Do-

h Tal (fibrous) Same as for (a)

i Tetomile -Do-

3 Coal Dust

1 For airborne dust having not 2 mg per cubic metres

more than 5% silicon dioxide

by weight

2 For airborne dust having more As for item (2) of quartz

than 5% silicon dioxide by

weight

Table -3

Permissible limit for exposure

Substances

Ppm Mg/m3

Acetic anhydride 5 20

O-Dichlorobenzene 50 300

Formaldehyde 2 3

Hydrogen chloride 5 7

Manganese & compound (as

- 5

Mn)

Nitrogen dioxide 5 9

Nitro-glycerine- skin 0.2 2

Potassium hydroxide - 2

Sodium hydroxide - 2

-2 2,4,6, -

- 0.5

Trinitrotoluene (TNT)