-
ORR # 2000-074
DEPARTMENT OF CONSUMER AND INDUSTRY SERVICES DIRECTOR’S OFFICE
OCCUPATIONAL HEALTH STANDARDS—AIR CONTAMINANTS FOR CONSTRUCTION
Filed with the Secretary of State on January 15, 2002.
These rules take effect 7 days after filing with the Secretary of State
(By authority conferred on the director of the department of consumer and industry services by sections 14 and 24 of 1974 PA 154 and Executive Reorganization Orders Nos. 1996-1 and 1996-2, MCL 408.1014,
408.1024, 330.3101, and 445.2001)
R 325.60151 Construction air contaminants.
Rule 1. (1) An employer shall ensure that employee exposures to inhalation, ingestion, skin absorption, or contact with any material or substance at a concentration above those specified in the "Threshold Limit Values of Airborne Contaminants for 1970" of the American Conference of Governmental Industrial Hygienists, as listed in R 325.60154 to R 325.60161, are avoided.
(2) To achieve compliance with subrule (1) of this rule, an employer shall ensure that administrative or engineering controls are implemented whenever feasible. If administrative or engineering controls are not feasible to achieve full compliance, then protective equipment or other protective measures shall be used to keep the exposure of employees to air contaminants within the limits prescribed in this rule. Any equipment and technical measures used for this purpose shall first be approved for each particular use by a competent industrial hygienist or other technically qualified person. Respirators shall be used in a manner that is in compliance with R 325.60051 et seq., Part 451. respiratory protection.
(3) R 325.51401 et seq., Part 302. vinyl chloride, of the MIOSHA Occupational Health Standards for General Industry applies to the
exposure of every employee to vinyl chloride in every employment and place of employment covered by these rules in place of any different standard on exposure to vinyl chloride that would otherwise be applicable by virtue of subrule (1) of this rule.
(4) These rules replace O.H. rule 6201.
(5) The “Threshold Limit Values (TLV) of the American Conference of Governmental Industrial Hygienists (A.C.G.I.H.) for 1970” appear in R 325.60153 to R 325.60161. The Threshold Limit Values identified in these administrative rules as Maximum Allowable Concentrations (MAC) are specified in the rules that follow.
R 325.60152 Definitions pertaining to contaminants.
Rule 2. As used in these rules:
(a) “Maximum allowable concentration” or “MAC” means the threshold limit value or the time-weighted average 8-hour airborne concentration of a contaminant to which a person may be safely exposed.
(b) “Mg/m3” means milligrams of particulate per cubic meter of air.
(c) “Mppcf” means millions of particulates per cubic foot of air based on impinger samples counted by light field microscopic techniques.
(d) “Non- respirable atmosphere” means an atmosphere which contains insufficient oxygen, or an elevated level of contaminants which may render a person incapable of self-rescue.
(e) “Ppm” means parts of vapor or gas per million parts of air by volume at 25 degrees Celsius and 760 millimeters of mercury pressure.
(f) “Source” means a process or equipment that releases a contaminant into the air in concentrations exceeding the MAC.
R 325.60153 Contaminants; exposures; MAC.
Rule 3. (1) An employer shall not allow an employee to be exposed to a contaminant at concentrations in excess of the MAC as listed in R 325.60154 to R 325.60161.
(2) An employer shall not allow an employee to be exposed to a contaminant or combination of contaminants in concentrations that are hazardous or injurious to the person's health.
R 325.60154 Maximum allowable concentrations.
Rule 4. (1) Maximum allowable concentrations of air contaminants based on a repeated 8-hour work day exposure are listed in tables 1 to 7 in R 325.60155 to R 325.60161.
(2) A substance in tables 1 to 6 that is preceded by the letter A, C, or S is an especially hazardous contaminant and all the following precautions shall be taken:
(a) If the substance is preceded by the letter "A", then an employer shall ensure that an employee or any part of an employee’s anatomy is not exposed to, or allowed to come in contact with, the substance by means of any respiratory, oral, or skin route.
(b) If the substance is preceded by the letter "C", then its MAC means the highest concentration at which an employer may allow a person to be exposed at any time. This concentration is commonly referred to as a “ceiling.”
(c) If the substance is preceded by the letter "S", then an employer shall ensure that precautions are taken to prevent skin absorption.
R 325.60155 Maximum allowable concentrations for substances; A and B.
Rule 5. Table 1. Substances A and B
MAC
Substance ppm mg/m3
Abate --- 15
Acetaldehyde 200 360
Acetic acid 10 25
Acetic anhydride 5 20
Acetone 1,000 2,400
Acetonitrile 40 70
Acetylene Inert gas
Acetylene
dichloride, see 1,2-Dichloroethylene
Acetylene
tetrabromide
1
14
Acrolein
0.1
0.25
S
Acrylamide
---
0.3
S
Acrylonitrile
(see
R
325.51501
et
seq.*)
S
Aldrin
---
0.25
S
Allyl alcohol
2
5
Allyl chloride 1 3
C Allyl glycidyl ether (AGE) 10 45
Allyl propyl disulfide 2 12
Alundum, (Al203) Inert dust
2-Aminoethanol, see Ethanolamine
2-Aminopyridine 0.5 2
Ammonia 50 35
Ammonium sulfamate (amate) --- 15
n-Amyl acetate 100 525
sec-Amyl acetate 125 650
S Aniline 5 19
S Anisidine (o,p-isomers) --- 0.5
Antimony & compounds (as Sb) --- 0.5
ANTU (alpha naphthyl thiourea) --- 0.3
Argon Inert gas
Arsenic, inorganic compounds (see R 325.51601 et seq.*)
Arsenic, organic compounds (as As) --- 0.5
Arsine 0.05 0.2
S Azinphos-methyl --- 0.2
Barium (soluble compounds) --- 0.5
S,C Benzene (benzol) (see R 325.77101 et seq.*)
A,S Benzidine --- ---
P-Benzoquinone, see Quinone
Benzoyl peroxide --- 5
Benzyl chloride 1 5
Beryllium --- 0.002
Biphenyl, see Diphenyl
Bisphenol A, see Diglycidyl ether
Boron oxide
---
15
Boron tribromide
1
10
C
Boron trifluoride
1
3
Bromine
0.1
0.7
Bromine pentafluoride
0.1
0.7
S
Bromoform
0.5
5
Butadiene (1,3-butadiene) (see R 325.50091 et seq.*)
Butanethiol, see Butyl mercaptan
2-Butanone
200
590
S
2-Butoxy ethanol (butyl cellosolve)
50
240
Butyl acetate (n-butyl acetate)
150
710
sec-Butyl acetate
200
950
tert-Butyl acetate
200
950
Butyl alcohol
100
300
sec-Butyl alcohol
150
450
tert-Butyl alcohol
100
300
S,C
Butylamine
5
15
S,C
tert-Butyl chromate (as Cr03)
---
0.1
n-Butyl glycidyl ether (BGE)
50
270
Butyl mercaptan
0.5
1.5
p-tert-Butyltoluene
10
60
A See R 325.60154(2).
C See R 325.60154(2).
S See R 325.60154(2).
* Caution--these rules contain extensive requirements for exposure to these substances.
R 325.60156 Maximum allowable concentrations for substances; C and D. Rule 6. Table 2. Substances C and D
MAC
Substance ppm mg/m3
Cadmium (metal dust and soluble salts) (see R 325.51851 et
seq.*)
C Cadmium oxide fume (as Cd) (see R 325.51851 et seq.*)
Calcium arsenate --- 1
Calcium carbonate Inert dust
Calcium oxide --- 5
Camphor (synthetic) 2 ---
Carbaryl (Sevin®) --- 5
Carbon black --- 3.5
Carbon dioxide 5,000 9,000
S Carbon disulfide 20 60
Carbon monoxide 50 55
S,C Carbon tetrachloride 10 65
Cellulose (paper fiber) Inert dust
S Chlordane --- 0.5
S Chlorinated camphene --- 0.5
Chlorinated diphenyl oxide --- 0.5
Chlorine 1 3
Chlorine dioxide 0.1 0.3
C Chlorine trifluoride 0.1 0.4
C Chloroacetaldehyde 1 3
alpha-Chloroacetophenone (phenacylchloride) 0.05 0.3
Chlorobenzene (monochlorobenzene) 75 350
o-Chlorobenzylidene malononitrile (OCBM) 0.05 0.4
Chlorobromomethane 200 1,050
2-Chloro-1,3-butadiene, see Chloroprene
S Chlorodiphenyl (42% Chlorine) --- 1
S Chlorodiphenyl (54% Chlorine) --- 0.5
1-Chloro-2,3-epoxypropane, see Epichlorohydrin 2-Chloroethanol, see Ethylene chlorohydrin Chloroethylene, see Vinyl chloride
C Chloroform (trichloromethane) 50 240
1-Chloro-1-nitropropane 20 100
Chloropicrin 0.1 0.7
S Chloroprene (2-chloro-1,3-butadiene) 25 90
Chromic acid and chromates (as Cr03) --- 0.1
Chromium, sol. chromic & chromous salts (as Cr) --- 0.5
Metal & insol. salts --- 1
Coal tar pitch volatiles (benzene soluble fraction: anthracene, BaP, phenanthrene, acridine, chrysene, pyrene) --- 0.2
Cobalt, metal fume & dust --- 0.1
Coke oven emissions (see R 325.50101 et seq.*)
Copper fume --- 0.1
Dusts and mists --- 1
Corundum (Al203) Inert dust
Cotton dust (raw) --- 1
Crag® herbicide --- 15
S Cresol (all isomers) 5 22
Crotonaldehyde 2 6
S Cumene 50 245
S Cyanide (as CN) --- 5
Cyanogen 10 ---
Cyclohexane 300 1,050
Cyclohexanol 50 200
Cyclohexanone 50 200
Cyclohexene 300 1,015
Cyclopentadiene 75 200
2,4-D --- 10
S DDT (Dichlorodiphenyltrichloroethane) --- 1
DDVP, see Dichlorvos
S Decaborane 0.05 0.3
S Demeton® --- 0.1
Diacetone alcohol (4-hydroxy-4-methyl-2-pentanone) 50 240
1,2-Diainoethane, see Ethylenediamine
Diazomethane 0.2 0.4
Diborane 0.1 0.1
S,C 2-Dibromoethane (ethylene dibromide) 25 190
Dibutyl phosphate 1 5
Dibutyl phthalate --- 5
C Dichloroacetylene 0.1 0.4
C o-Dichlorobenzene 50 300
p-Dichlorobenzene 75 450
Dichlorodifluoromethane 1,000 4,950 1,3-Dichloro-5,5-dimethyl hydantoin --- 0.2
1,1-Dichloroethane 100 400
1,2-Dichloroethane 50 200
1,2-Dichloroethylene 200 790
S,C Dichloroethyl ether 15 90
Dichloromethane, see Methylene chloride
Dichloromonofluoromethane
1,000
4,200
C
1,1-Dichloro-l-nitroethane
10
60
1,2-Dichloropropane, see Propylene dichloride
Dichlorotetrafluoroethane
1,000
7,000
S
Dichlorvos (DDVP)
---
1
S
Dieldrin
---
0.25
Diethyl
25
75
S
Diethylamino, ethanol
10
50
S,C
Diethylene triamine
10
42
Diethyl ether, see Ethyl ether
Difluorodibromomethane
100
860
C
Diglycidyl ether (DGE)
0.5
2.8
Dihydroxybenzene, see Hydroquinone
Diisobutyl ketone
50
290
S
Diisopropylamine
5
20
Dimethoxymethane, see Methylal
S
Dimethyl acetamide
10
35
Dimethylamine
10
18
Dimethylaminobenzene, see Xylidene
S
Dimethylaniline (N-dimethylaniline)
5
25
Dimethylbenzene, see Xylene
Dimethyl-1,2-dibromo-2,2-dichloroethyl phosphate
---
3
(Dibrom®)
S Dimethylformamide 10 30
2,6-Dimethylheptanone, see Diisobutyl ketone
S 1,1-Dimethylhydrazine 0.5 1
Dimethylphthalate --- 5
S Dimethylsulfate 1 5
S Dinitrobenzene (all isomers) --- 1
S Dinitro-o-cresol --- 0.2
S Dinitrotoluene --- 1.5
S Dioxane (diethylene dioxide) 100 360
Diphenyl 0.2 1
Diphenyl amine --- 10
Diphenylmethane diisocyanate, see Methylene bisphenyl isocyanate (MDI)
S
Dipropylene glycol methyl ether
100
600
Di-sec,octyl phthalate (di-2-ethylhexylphthalate)
---
5
A See R 325.60154(2). C See R 325.60154(2). S See R 325.60154(2).
* Caution--these rules contain extensive requirements for exposure to these substances.
R 325.60157 Maximum allowable concentrations for substances; E to H. Rule 7. Table 3. Substances E to H
MAC
Substance ppm mg/m3
Emery Inert dust
S Endosulfan (Thiodan®) --- 0.1
S Endrin --- 0.1
S Epichlorohydrin 5 19
S EPN --- 0.5
1,2-Epoxypropane, see Propylene oxide 2,3-Epoxy-l-propanol, see Glycidol
Ethane Inert gas
Ethanethiol, see Ethyl mercaptan
Ethanolamine
3
6
S
2-Ethoxyethanol
200
740
S
2-Ethoxyethylacetate (cellosolve acetate)
100
540
Ethyl acetate
400
1,400
S
Ethyl acrylate
25
100
Ethyl alcohol (ethanol)
1,000
1,900
Ethylamine
10
18
Ethyl sec-amyl ketone (5-methyl-3-heptanone)
25
130
Ethyl benzene
100
435
Ethyl bromide
200
890
Ethyl butyl ketone (3-heptanone)
50
230
Ethyl chloride
1,000
2,600
Ethyl ether
400
1,200
Ethyl formate
100
300
Ethyl mercaptan
0.5
1
Ethyl silicate
100
850
Ethylene
Inert
gas
S
Ethylene chlorohydrin
5
16
Ethylenediamine
10
25
Ethylene dibromide, see 1,2-Dibromoethane
Ethylene dichloride, see 1,2-Dichloroethane
S,C Ethylene glycol dinitrate and/or Nitroglycerin 0.2
Ethylene glycol monomethyl ether acetate, see Methyl cellosolve acetate
S Ethyleneimine 0.5 1
Ethylene oxide (see R 325.51151 et seq.*)
Ethylidine chloride,
see
1,1-Dichloroethane
S
N-Ethylmorpholine
20
94
Ferbam
---
15
Ferrovanadium dust
---
1
Fibrous glass
Inert
dust
Fluoride (as F) --- 2.5
Fluorine 0.1 0.2
Fluorotrichloromethane 1,000 5,600 C Formaldehyde (see R 325.51451 et seq.*)
Formic acid 5 9
S Furfural 5 20
Furfuryl alcohol 50 200
Gasoline (limits will be based on aromatic hydrocarbons in mixture) Glycerine mist Inert mist
Glycidol (2,3-epoxy-l-propanol) 50 150
Glycol monoethyl ether, see 2-Ethoxyethanol
Graphite (synthetic) Inert dust
Guthion®, see Azinphos-methyl
Gypsum Inert dust
Hafniun --- 0.5
Helium Inert gas
S Heptachlor --- 0.5
Heptane (n-heptane) 500 2,000
S Hexachloroethane 1 10
S Hexachloronaphthalene --- 0.2
Hexane (n-hexane) 500 1,800
2-Hexanone 100 410
Hexone (methyl isobutyl ketone) 100 410
sec-Rexyl acetate 50 300
S Hydrazine 1 1.3
Hydrogen Inert gas
Hydrogen bromide 3 10
C Hydrogen chloride 5 7
S Hydrogen cyanide 10 11
Hydrogen fluoride 3 2
Hydrogen peroxide 1 1.4
Hydrogen selenide 0.05 0.2
Hydrogen sulfide 10 15
Hydroquinone --- 2
A See R 325.60154(2). C See R 325.60154(2). S See R 325.60154(2).
* Caution--these rules contain extensive requirements for exposure to these substances.
R 325.60158 Maximum allowable concentrations for substances; I to M. Rule 8. Table 4. Substances I to M
MAC
Substance ppm mg/m3
Indene 10 45
Indium and compounds (as In) --- 0.1
C Iodine 0.1 1
Iron oxide fume --- 10
Iron salts, soluble (as Fe) --- 1
Isoamyl acetate 100 525
Isoamyl alcohol 100 360
Isobutyl acetate 150 700
Isobutyl alcohol 100 300
Isophorone 25 140
Isopropyl acetate 250 950
Isopropyl alcohol 400 980
Isopropylamine 5 12
Isopropyl ether 500 2,100
Isopropyl glycidyl ether (IGE) 50 240
Kaolin Inert dust
Ketene 0.5 0.9
Lead and lead compounds (see R 325.51991 et seq.*)
Limestone Inert dust
S Lindane --- 0.5
Lithium hydride --- 0.025
L.P.G. (liquified petroleum gas) 1,000 1,800 Magnesite Inert dust
Magnesium oxide fume 15
S Malathion --- 15
Maleic anhydride 0.25 1
C Manganese and compounds (as Mn) --- 5
Marble Inert dust
S Mercury
---
0.1
S
Mercury (organic compounds)
---
0.01
Mesityl oxide
25
100
Methane
Inert
gas
Methanethiol, see Methyl mercaptan
Methoxychlor
---
15
2-Methoxyethanol, see Methyl cellosolve
Methyl acetate
200
610
Methyl acetylene (propyne)
1,000
1,650
Methyl acetylene-propadiene mixture (MAPP)
1,000
1,800
S
Methyl acrylate
10
35
Methylal (dimethoxymethane)
1,000
3,100
Methyl alcohol (methanol)
200
260
Methylamine
10
12
Methyl amyl alcohol, see Methyl isobutyl carbinol
Methyl (n-amyl) ketone (2-heptanone)
100
465
S,C
Methyl bromide
20
80
Methyl butyl ketone, see 2-Hexanone
S
Methyl cellosolve
25
80
S
Methyl cellosolve acetate
25
120
C
Methyl chloride
100
210
Methyl chloroform
350
1,900
Methylcyclohexane
500
2,000
Methylcyclohexanol
100
470
S o-Methylcyclohexanone 100 460
Methylenedianiline (MDA) (see R 325.51651 et seq.*) Methyl ethyl ketone (MEK), see 2-Butanone
Methyl formate 100 250
S Methyl iodide 5 28
Methyl isoanyl ketone 100 475
S Methyl isobutyl carbinol 25 100
Methyl isobutyl ketone, see Hexone
S Methyl isocyanate 0.02 0.05
Methyl mercaptan 0.5 1
Methyl methacrylate 100 410
Methyl propyl ketone, see 2-Pentanone
C Methyl silicate 5 30
C alpha-Methyl styrene 100 480
C Methylene bisphenyl isocyanate (MDI) 0.02 0.2
Methylene chloride (dichloromethane) (see R 325.51651 et seq.*) Molybdenum (soluble compounds) --- 5
(insoluble compounds) --- 15
S Monomethyl aniline 2 9
S,C Mouomethyl hydrazine 0.2 0.35
S Morpholine 20 70
A See R 325.60154(2). C See R 325.60154(2). S See R 325.60154(2).
* Caution--these rules contain extensive requirements for exposure to these substances.
R 325.60159 Maximum allowable concentrations for substances; N to P. Rule 9. Table 5. Substances N to P
MAC
Substance ppm mg/m3
Naphtha (coal tar) 100 400
Naphtha (petroleum)(MAC will be based on aromatic hydrocarbons in mixture)
Naphthalene 10 50
A beta-Naphthylamine ---
Neon Inert gas
Nickel carbonyl 0.001 0.007
Nickel, metal and soluble compounds (as Ni) --- 1
S Nicotine --- 0.5
Nitric acid 2 5
Nitric oxide 25 30
S p-Nitroaniline 1 6
S Nitrobenzene 1 5
S p-Nitrochlorobenzene --- 1
Nitroethane 100 310
Nitrogen Inert gas
Nitrogen dioxide 5 9
Nitrogen trifluoride 10 29
S Nitroglycerin 0.2 2
Nitromethane 100 250
1-Nitropropane 25 90
2-Nitropropane 25 90
S,A N-Nitrosodimethylamine (dimethylnitrosomine) ---
S Nitrotoluene 5 30
Nitrotrichloromethane, see Chloropicrin
Nitrous oxide Inert gas
S Octachloronaphthalene --- 0.1
Octane 400 1,900
Oil mist, particulate --- 5
Oil mist, vapor (MAC will be based on aromatic hydrocarbons in mixture)
Osmium tetroxide --- 0.002
Oxalic acid --- 1
Oxygen difluoride 0.05 0.1
Ozone 0.1 0.2
S Paraquat --- 0.5
S Parathion --- 0.1
Pentaborane 0.005 0.01
S Pentachloronaphthalene --- 0.5
S Pentachlorophenol --- 0.5
Pentaerythritol Inert particulate
Pentane 500 1,500
2-Pentanone 200 700
Perchloroethylene 100 670
Perchloromethyl mercaptan 0.1 0.8
Perchloryl fluoride 3 13.5
Petroleum distillates (naphtha)(MAC will be based on aromatic
hydrocarbons in mixture)
S
Phenol
5
19
S
p-Phenylene diamine
---
0.1
Phenyl ether (vapor)
1
7
Phenyl ether-biphenyl
mixture
(vapor)
1
7
Phenylethylene, see Styrene
Phenyl glycidyl
ether
(PGE)
10
60
S
Phenylhydrazine
5
22
S Phosdrin (Mevinphos®) --- 0.1
Phosgene (carbonyl chloride) 0.1 0.4
Phosphine 0.3 0.4
Phosphoric acid --- 1
Phosphorus (yellow) --- 0.1
Phosphorus pentachloride --- 1
Phosphorus pentasulfide --- 1
Phosphorus trichloride 0.5 3
Phthalic anhydride 2 12
S Picric acid --- 0.1
Pival® (2-pivalyl-1,3-indandione) --- 0.1
Plaster of Paris Inert dust
Platinim, soluble salts (as Pt) --- 0.002
Polytetrafluoroethylene decomposition products, see Teflon® decomposition products
Propane
Inert
gas
S
Propargyl alcohol
1
---
A
beta-Propiolactone
---
n-Propyl acetate
200
840
Propyl alcohol
200
500
n-Propyl nitrate
25
110
Propylene bichloride 75 350
S Propylene imine 2 5
Propylene oxide 100 240
Propyne, see Methyl acetylene
Pyrethrum --- 5
Pyridine 5 15
A See R 325.60154(2). C See R 325.60154(2). S See R 325.60154(2).
R 325.60160 Maximum allowable concentrations for substances; Q to Z. Rule 10. Table 6. Substances Q to Z
MAC
Substance ppm mg/m3
Quinone 0.1 0.4
S RDX --- 1.5
Rhodium, metal fume, dusts, and insoluble compounds
(as Rh) --- 0.1
Rhodium, soluble compounds (as Rh) --- 0.001
Ronnel --- 10
Rotenone (commercial) --- 5
Rouge Inert dust
Selenium compounds (as Se) --- 0.2
Selenium hexafluoride 0.05 0.4
Silicon carbide Inert dust
Silver, metal and soluble compounds --- 0.01
S Sodium fluoroacetate (1080) --- 0.05
Sodium hydroxide --- 2
Starch Inert dust
Stibine 0.1 0.5
Stoddard solvent 200 1,150
Strychnine --- 0.15
C Styrene monomer (phenylethylene) 100 420
Sucrose Inert dust
Sulfur dioxide 5 13
Sulfur hexafluoride 1,000 6,000 Sulfuric acid --- 1
Sulfur monochloride 1 6
Sulfur pentafluoride 0.025 0.25
Sulfuryl fluoride 5 20
Systox, see Demeton®
2,4,5T --- 10
Tantalum --- 5
S TEDP --- 0.2
Teflon® decomposition products (maintain minimal air concentration)
Tellurium
---
0.1
Tellurium hexafluoride
0.02
0.2
S
TEPP
---
0.05
C
Terphenyls
1
9
1,1,1,2-Tetrachloro-2,2-difluoroethane
500
4,170
1,1,2,2-Tetrachloro-1,2-difluoroethane
500
4,170
S
1,1,2,2-Tetrachloroethane
5
35
Tetrachloroethylene, see Perchloroethylene
S
Tetrachloromethane, see Carbon tetrachloride Tetrachloronaphthalene
---
2
S
Tetraethyl lead (as Pb)
---
0.075a
Tetrahydrofuran
200
590
S
Tetramethyl lead (THL) (as Pb)
---
0.150
S
Tetramethyl succinonitrile
0.5
3
Tetranitromethane
1
8
S
Tetryl (2,4,6-trinitrophenylmethylnitramine)
---
1.5
S
Thallium, soluble compounds (as T1)
---
0.1
Thiram
---
5
Tin (inorganic compounds, except SnH4 and SnO2)
---
2
(organic compounds)
---
0.1
Tin oxide
Inert
particulate
Titanium dioxide
Inert
particulate
Toluene (toluol)
200
750
C
Toluene-2,4-diisocyanate
0.02
0.14
S
o-Toluidine
5
22
Toxaphene, see Chlorinated camphene
Tributyl phosphate
---
5
1,1,1-Trichloroethane, see Methyl chloroform
S
1,1,2-Trichloroethane
10
45
Trichloroethylene
100
535
Trichloromethane, see Chloroform
S
Trichloronaphthalene
---
5
1,2,3-Trichloropropane
50
300
1,1,2-Trichloro-1,2,2-trifluoroethane
1,000
7,600
Triethylamine
25
100
Trifluoromonobromomethane
1,000
6,100
Trimethyl benzene
25
120
2,4,6-Trinitrophenol, see Picric acid
2,4,6-Trinitrophenylmethylnitramine, see Tetryl
S
Trinitrotoluene
---
1.5
Triorthocresyl phosphate
---
0.1
Triphenyl phosphate
---
3
Tungsten and compounds (as W)
Insoluble
---
5
Soluble
---
1
Turpentine
100
560
Uranium (natural)
soluble & insoluble compounds (as U)
---
0.2
C
Vanadium (V2O5 dust)
---
0.5
(V2O5 fume)
---
0.1
Vinyl benzene, see Styrene
C Vinyl chloride (see R 325.51401 et seq.*) Vinyl cyanide, see Acrylonitrile
Vinyl toluene 100 480
Warfarin
---
0.1
Xylene (xylol)
100
435
S
Xylidine
5
25
Yttrium
---
1
Zinc chloride fume
---
1
Zinc oxide fume
---
5
Zirconium compounds
(as Zr)
---
5
A See R 325.60154(2). C See R 325.60154(2). S See R 325.60154(2).
aThe 1970 ACGIH standard for Tetraethyl lead is 0.100 mg/m3.
* Caution--these rules contain extensive requirements for exposure to these substances.
R 325.60161 Maximum allowable concentrations for mineral dusts.
Rule 11. Table 7. Mineral dusts
Substance
MAC (mppcf)
Silica
Crystalline *
Quartz
Cristobalite
Amorphous, including natural diatomaceous earth
MAC = 250
% SiO2+5
MAC same as quartz 20
Silicates (less than 1% crystalline silica)
20
Asbestos, all types (see asbestos in
construction R 325.51301 et seq.)
Mica
Portland cement
50
Soapstone
20
Talc (non-asbestiform)
20
Talc (fibrous) (see asbestos in
construction R 325.51301 et seq.)
Tremolite (see asbestos in
construction R 325.51301 et seq.)
Graphite (natural)
15
Inert or nuisance particles **
50 of total dust less than 1% SiO2 (or 15 mg/m3, whichever is the smaller)
* The percentage of crystalline silica, SiO2, in the formula is the amount determined from airborne samples.
** The following are some examples of inert or nuisance particulates when toxic impurities are not present; e.g. quartz less than 1%.
Alundum (A1203)
Gypsum
Rouge
Calcium carbonate
Limestone
Silicon carbide
Cellulose
Magnesite
Starch
Corundum (A1203)
Marble
Sucrose
Emery
Pentaerythritol
Tin oxide
Glycerine mist
Plaster of Paris
Titanium dioxide
Graphite (synthetic)
Portland cement
Vegetable oil mists (except castor, cashew nut, or similar irritant oils)
