Rule 111: Permissible limits of certain chemical substance in work environment under section 88

111. Permissible limits of certain chemical substance in work environment under section 88.- Without prejudice to the requirements in any other provisions in the Code or the rules, the requirements specified in this schedule shall apply to all factories. भाग‍4(ग) ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍राजस्‍ थान‍राज-पत्र,‍जून‍30,‍2026‍‍‍‍‍‍‍‍ ‍‍ ‍597 Schedule 1. Definitions.- For the purpose of this schedule,- (a) "mg/m3" means milligrams of a substance per cubic meter of air: (b) "mppcm" means a million particles of a substance per cubic meter of air; (c) "ppm" means parts of vapour or gas per million parts air by volume at 25°C 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 CI 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 concentrations of substances at work locations.- (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 time weighted 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 598 ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍राजस्‍थान‍राज-पत्र,‍जून‍30,‍2026‍‍‍‍‍ ‍‍‍‍‍ ‍भाग‍4(ग) 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 track. (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/L1 + C2/L2 +....... Cn/Ln should not exceed unity when C1 C2 ... Cn are the time weighted concentration of toxic substance 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 substance 1, 2, ... and n respectively. (b) In case the air at any work location contains a mixture of substances, mentioned in Table 1, 2 or 3 and these do not have similar toxic properties, that 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 clause 2 (1) and 2 (2). 3. Sampling and evaluation procedures.- (1) Notwithstanding provisions in any other clauses, the sampling and evaluation procedures to be adopted for checking compliance with the provision in the schedule shall be as per standard procedure in vogue, from time to time. (2) Notwithstanding the provisions in clause 5, the following conditions regarding the sampling and evaluation procedures relevant to checking compliance with the provisions in this schedule are specified:- (a) For determination of the number of particles, per cubic meter in item 1 (a) (i) (1) in Table 2, samples are to be collected by standard or midget impinger and the counts made by light-field technique. (b) The percentage of quartz in the 3 formulae given in item 1 (a) (i) of Table 2 is to be determined from air borne samples. (c) For determination of number of fibres as specified in item 2 (a) of Table 2, the membrane filter method at 430 magnification (4 mm. objective) phase contrast illumination should be used. (d) Both for determination of concentration and percentage of quartz for use of the formula given in item 1 (a) (i) (2) of Table 2, the fraction passing through a size- selector with the following characteristics should only be considered:- Aerodynamic diameter Percentage allowed by (Unit density Sphere) size-selector 2.0 90 2.5 75 3.5 50 भाग‍4(ग) ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍राजस्‍ थान‍राज-पत्र,‍जून‍30,‍2026‍‍‍‍‍‍‍‍ ‍‍ ‍599 5.0 25 10.0 0 4. 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 assess merit and also a record of the same kept readily available for inspection by an Inspector-cum-Facilitator. 5. Exemption.- If in respect of any factory or a part of factory, the Chief Inspector-cum- Facilitator is satisfied that, by virtue of the pattern of working time of the workers at different work location or an account of other circumstances, no worker is exposed, in the air at the work locations, to a substance or substances specified in Table 1, 2 or 3 to such an extent as is likely to be injurious to his health, the Chief Inspector-cum-Facilitator may by an order in writing, exempt the factory or a part of the factory from the requirements in clause 2, subject to such conditions, if any as he may specify therein. Permissible limits Table 1 Substance Permissible limits of exposure Time weighted average Short term maximum concentration concentrated 1 2 3 3 ppm mg/m ppm mg/m3 Acetic acid 10 25 15 37 Acrolein 0.1 0.25 0.03 0.8 Aldrin-skin - 0.25 - 0.75 Anisidine (o-poisonous)-skin 0.1 0.5 - - Ammonia 25 18 35 27 Aniline Skin 2 10 5 20 Arsenic & Compound (as) - 0.2 - - Benzene 10 30 - - Bromine 0.1 0.7 0.3 2 2 Butanene Methyl ethyl 200 590 300 885 (Ketone-MEK) n-Butyl acetate 150 710 200 950 Sec/ter. Butyl acetate 200 950 250 1190 Cadmium-dust and salts (as Cd) - 0.05 - 0.2 Calcium Oxide - 2 - - Carbaryl (Sovin) - 5 - 10 Carbofuran (Furadan) - 0.1 - - 600 ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍राजस्‍थान‍राज-पत्र,‍जून‍30,‍2026‍‍‍‍‍ ‍‍‍‍‍ ‍भाग‍4(ग) Carbon disulphide- skin 2 60 30 90 Carbon monoxide 50 55 400 440 Carbon tetrachloride- skin 10 65 20 130 Carbonyl chloride (Phosgene) 0.1 0.4 - - Chlordane-skin - 0.5 - 2 Chlorobenzene (mono chloro- 75 350 - - benzene) Chlorine 1 3 3 9 bis-chloromethyl ether .001 - - - Chromic acid and chromates (as - 0.05 - - Cr.) Chromium, Sol. Chromic - 0.5 - - Chromous Salts (as Cr.) Copper Fume - 0.2 - - Cotton Dust, raw - 0.2 - 0.6 Cresol, all isomers skin 5 22 - - Cyanides, as CN skin - 5 - - Cyanogen 10 20 - - DDT (Dichloro-diphenyl- - 1 - 3 trichloroethane) Dameton- skin 0.01 0.1 0.03 0.3 Diazion- skin - 0.1 - 0.3 Dibutyl Phthalate - 5 - 10 Dichlorves (DDVP) skin 0.01 1 0.03 3 Dieldrin- skin - 0.25 - 0.75 Dinitro Benzene (all isomers) 0.15 1 0.5 3 skin Dinitro toluene skin - 1.5 - 5 Diphenyl 0.2 1.5 0.6 4 Endosulfan (Thiodan) skin - 0.1 - 0.3 Endrin-skin - 0.1 - 0.3 Ethyl acetate 400 1000 - - Ethyl alcohol 1000 1900 - - Ethyl amine 10 18 - - Fluorides (as F) - 2.5 - - Fluorine 1 2 2 4 Hydrogen Cyanide- Skin 10 11 15 16 Hydrogen Sulphide 10 15 15 27 Iron Oxide Fume (Fe2O3 as Fe) - 5 - 10 Isoamyl acetate 100 525 125 655 Isoamyl alcohol 100 360 125 450 Isobutyl alcohol 50 150 75 225 Lead, inorg, fumes and dusts (as - 0.15 - 0.45 Pb) Lindane -skin - 0.5 - 1.5 Melathion- skin - 10 - - भाग‍4(ग) ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍राजस्‍ थान‍राज-पत्र,‍जून‍30,‍2026‍‍‍‍‍‍‍‍ ‍‍ ‍601 Manganese fume (as Mn) - 1 - 3 Mercury (as Hg) - 0.05 - 0.15 Mercury (alkyl compounds) skin 0.001 0.01 0.003 0.03 (as Hg) Methyl alcohol (methanel) skin 200 260 250 310 Methyl cellosolve skin (2 25 80 35 120 methoxy ethanol) Methyl isobutyl Ketone skin 100 410 125 510 Naphthalene 10 50 15 75 Nickel carbonyl (as Ni) 0.05 0.35 - - Nitiric acid 2 5 4 10 Nitric oxide 25 30 35 45 Nitrobenzene- skin 1 5 2 10 Oil Mist mineral - 5 - 10 Parathion skin - 0.1 - 0.3 Phenel skin 5 19 10 38 Phorate (Thimet) skin - 0.05 - 0.2 Phosgene (carbonyl chloride) 0.1 0.4 - - Phosphine 0.3 0.4 1 1 Phosphours Pentachloride - 1 - 3 Phosphours Trichloride 0.5 3 - - Picric acid skin - 0.1 - 0.3 Phosphorus (yellow) - 0.1 - 0.3 Pyridine 5 15 10 30 Silane (silicon tetrahydride) 0.5 0.7 1 1.5 Styrene, monower (Phenyl 100 420 125 525 ethylene) Sulphure dioxide 5 13 - - Sulphuric acid - 1 - - Toluene (toluol)- skin 100 375 150 560 O-Toludine 5 22 10 44 Trichloroethylene 100 535 150 800 Vinyl Chloride 5 10 - - Welding fumes (NOC) - 5 - - Xylene (o-m-isomers) skin 100 435 150 655 Table 2 Substance Permissible time weighted average 1 concentration 2 1. Silica (a) Crystalline (i) Quartz (1) In terms of dust count mppcm 602 ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍राजस्‍थान‍राज-पत्र,‍जून‍30,‍2026‍‍‍‍‍ ‍‍‍‍‍ ‍भाग‍4(ग) (2) In terms of repairable dust mg/m3 (3) In terms of total dust mg/m3 (ii) Cristobalite Half the limits given against quartz. (iii) Tridymite Half the limits given against quartz. (iv) Silica fused. Same limit as for quartz. (v) Tripoli Same limit as in formula in items 2 given against quartz. (b) Amorphous 705 mppcm. 2. Silicate having less than 1% free silica by weight (a) Asbestos fibres longer than 5 microne. (i) Amosite 0.5% fibre/cubic centimeter. (ii) Chrysolite 2% fibre/cubic centimeter. (iii) Crocidolite 0.2% fibre/cubic centimeter. (iv) Other form 2% fibre/cubic centimeter. (b) Mica 705 mppcm (c) Mineral wool fibre 10 mg/m3 (d) Porlite 1060 mppcm (e) Portland cement 1060 mppcm (f) Soapstone 705 mppcm (g) Talc (nonobosti form) 705 mppcm (h) Talc (fibrous) Same limits as for asbestos (I) Tromolite Same limits as for asbestos 3. Coal dust (1) For airborne dust having less than 2 mg/m3 5% silicon dioxide by weight (2) For airborne dust having over 5% Same limit as prescribed by formula in silicon dioxide. item (2) against quartz. भाग‍4(ग) ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍राजस्‍ थान‍राज-पत्र,‍जून‍30,‍2026‍‍‍‍‍‍‍‍ ‍‍ ‍603 Table 3 Permissible limit of Substance exposure ppm mg/m3 Acetic anhydride 5 20 O- Dichlorbenzene 50 300 Formaldehyde 2 3 Hydrogen chloride 5 7 Manganese & Compounds (as Mn) - 5 Nitrogen dioxide 5 9 Nitroglycerin- skin 0.2 2 Potassium Hydroxide - 2 Sodium hydroxide - 2 2, 4, 6,- Trinitrotoluene (TNT) - 0.5