Indiana Soil Gas Screening Levels
IDEM soil gas screening levels for vapor intrusion. Subslab, deep exterior, and shallow exterior values for 3 land uses. 154 chemicals.
Overview
Indiana’s soil gas screening levels allow direct comparison of soil gas measurements to regulatory thresholds without requiring an attenuation factor calculation. They are derived by applying IDEM’s published attenuation factors to the indoor air published levels, working backwards to the subsurface concentration that would produce an indoor air concentration at or below the indoor air published level. Published in the IDEM Risk-based Closure Guide (WASTE-0046-R2, “the R2”), effective March 28, 2025.
Two sampling categories, six columns:
IDEM publishes soil gas levels for two depth categories and three land use scenarios:
- Subslab and deep exterior (>5 feet depth): Soil gas collected from beneath a slab or from exterior probes deeper than 5 feet below grade. These columns are derived with an attenuation factor of 0.03 for the residential and commercial scenarios, which makes them the less stringent (higher) of the two sets of screening levels.
- Shallow exterior (within 5 feet of ground surface): Soil gas collected from shallow exterior probes. These columns are derived with an attenuation factor of 0.1 for the residential and commercial scenarios. A higher attenuation factor produces lower (more stringent) screening levels, because each screening level is the indoor air published level divided by the attenuation factor - the shallow exterior columns are the more stringent set. The large commercial columns use smaller attenuation factors (0.003 for subslab and deep exterior, 0.01 for shallow exterior) per R2 Appendix A.
Three land use scenarios:
- Residential
- Commercial
- Large commercial (large, open commercial buildings qualifying under the R2 Section 3.3.4 lines of evidence: thick foundations and structural integrity, high ceilings and large building volumes, and high air exchange rates)
Risk basis: Derived from Indiana’s 1E-05 cancer risk, HQ of 1.0 indoor air published levels.
Qualifier key:
- C = Carcinogenic
- N = Noncarcinogenic
- S = Soil saturation cap
- D = Detection limit-based
Blank cells indicate no published soil gas level for that chemical in that scenario - not zero.
Unique to Indiana: Ohio’s CIDARS system does not publish soil gas screening levels. This is an Indiana-specific feature that simplifies vapor intrusion assessment by enabling direct soil gas measurement comparisons without attenuation factor calculations.
Soil Gas Screening Levels
Column headers:
- Sub/Deep Res = Subslab or deep exterior, residential (µg/m3)
- Sub/Deep Com = Subslab or deep exterior, commercial (µg/m3)
- Sub/Deep LgCom = Subslab or deep exterior, large commercial (µg/m3)
- Shallow Res = Shallow exterior, residential (µg/m3)
- Shallow Com = Shallow exterior, commercial (µg/m3)
- Shallow LgCom = Shallow exterior, large commercial (µg/m3)
Showing 154 of 154 chemicals
| Chemical | CAS Number | Sub/Deep Res (µg/m3) | Q | Sub/Deep Com (µg/m3) | Q | Sub/Deep LgCom (µg/m3) | Q | Shallow Res (µg/m3) | Q | Shallow Com (µg/m3) | Q | Shallow LgCom (µg/m3) | Q |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Acetaldehyde | 75-07-0 | 300 | N | 1,000 | N | 10,000 | N | 90 | N | 400 | N | 4,000 | N |
| Acetonitrile | 75-05-8 | 2,000 | N | 9,000 | N | 90,000 | N | 600 | N | 3,000 | N | 30,000 | N |
| Acrolein | 107-02-8 | 0.7 | N | 3 | N | 30 | N | 0.2 | N | 0.9 | N | 9 | N |
| Acrylic Acid | 79-10-7 | 7 | N | 30 | N | 300 | N | 2 | N | 9 | N | 90 | N |
| Acrylonitrile | 107-13-1 | 10 | C | 60 | C | 600 | C | 4 | C | 20 | C | 200 | C |
| Allyl Alcohol | 107-18-6 | 3 | N | 10 | N | 100 | N | 1 | N | 4 | N | 40 | N |
| Allyl Chloride | 107-05-1 | 30 | N | 100 | N | 1,000 | N | 10 | N | 40 | N | 400 | N |
| Ammonia | 7664-41-7 | 20,000 | N | 70,000 | N | 700,000 | N | 5,000 | N | 20,000 | N | 200,000 | N |
| Amyl Alcohol, tert- | 75-85-4 | 100 | N | 400 | N | 4,000 | N | 30 | N | 100 | N | 1,000 | N |
| Benzene | 71-43-2 | 100 | C | 500 | C | 5,000 | C | 40 | C | 200 | C | 2,000 | C |
| Benzene, Trimethyl | 25551-13-7 | 100 | N | 600 | N | 6,000 | N | 40 | N | 200 | N | 2,000 | N |
| Benzyl Chloride | 100-44-7 | 20 | C | 80 | C | 800 | C | 6 | C | 30 | C | 300 | C |
| Bis(2-chloroethyl)ether | 111-44-4 | 3 | C | 10 | C | 100 | C | 0.9 | C | 4 | C | 40 | C |
| Bis(chloromethyl)ether | 542-88-1 | 0.02 | C | 0.07 | C | 0.7 | C | 0.005 | C | 0.02 | C | 0.2 | C |
| Boron Trichloride | 10294-34-5 | 700 | N | 3,000 | N | 30,000 | N | 200 | N | 900 | N | 9,000 | N |
| Boron Trifluoride | 7637-07-2 | 500 | N | 2,000 | N | 20,000 | N | 100 | N | 600 | N | 6,000 | N |
| Bromo-2-chloroethane, 1- | 107-04-0 | 2 | N | 9 | N | 90 | N | 0.6 | N | 3 | N | 30 | N |
| Bromobenzene | 108-86-1 | 2,000 | N | 9,000 | N | 90,000 | N | 600 | N | 3,000 | N | 30,000 | N |
| Bromochloromethane | 74-97-5 | 1,000 | N | 6,000 | N | 60,000 | N | 400 | N | 2,000 | N | 20,000 | N |
| Bromodichloromethane | 75-27-4 | 30 | C | 100 | C | 1,000 | C | 8 | C | 30 | C | 300 | C |
| Bromoform | 75-25-2 | 900 | C | 4,000 | C | 40,000 | C | 300 | C | 1,000 | C | 10,000 | C |
| Bromomethane | 74-83-9 | 200 | N | 700 | N | 7,000 | N | 50 | N | 200 | N | 2,000 | N |
| Bromopropane, 1- | 106-94-5 | 300 | C | 1,000 | C | 10,000 | C | 80 | C | 300 | C | 3,000 | C |
| Butadiene, 1,3- | 106-99-0 | 30 | C | 100 | C | 1,000 | C | 9 | C | 40 | C | 400 | C |
| Butyl alcohol, sec- | 78-92-2 | 1,000,000 | N | 4,000,000 | N | 40,000,000 | N | 300,000 | N | 1,000,000 | N | 10,000,000 | N |
| Butyl Alcohol, t- | 75-65-0 | 200,000 | N | 700,000 | N | 7,000,000 | N | 50,000 | N | 200,000 | N | 2,000,000 | N |
| Carbon Disulfide | 75-15-0 | 20,000 | N | 100,000 | N | 1,000,000 | N | 7,000 | N | 30,000 | N | 300,000 | N |
| Carbon Tetrachloride | 56-23-5 | 200 | C | 700 | C | 7,000 | C | 50 | C | 200 | C | 2,000 | C |
| Carbonyl Sulfide | 463-58-1 | 3,000 | N | 10,000 | N | 100,000 | N | 1,000 | N | 4,000 | N | 40,000 | N |
| Chlorine | 7782-50-5 | 5 | N | 20 | N | 200 | N | 2 | N | 6 | N | 60 | N |
| Chlorine Dioxide | 10049-04-4 | 7 | N | 30 | N | 300 | N | 2 | N | 9 | N | 90 | N |
| Chloro-1,1-difluoroethane, 1- | 75-68-3 | 2,000,000 | N | 7,000,000 | N | 70,000,000 | N | 500,000 | N | 2,000,000 | N | 20,000,000 | N |
| Chloro-1,3-butadiene, 2- (Chloroprene) | 126-99-8 | 1 | C | 10 | C | 100 | C | 0.3 | C | 4 | C | 40 | C |
| Chlorobenzene | 108-90-7 | 2,000 | N | 7,000 | N | 70,000 | N | 500 | N | 2,000 | N | 20,000 | N |
| Chlorobenzotrifluoride, 4- | 98-56-6 | 100 | C | 500 | C | 5,000 | C | 30 | C | 100 | C | 1,000 | C |
| Chlorodifluoromethane | 75-45-6 | 2,000,000 | N | 7,000,000 | N | 70,000,000 | N | 500,000 | N | 2,000,000 | N | 20,000,000 | N |
| Chloroform | 67-66-3 | 40 | C | 200 | C | 2,000 | C | 10 | C | 50 | C | 500 | C |
| Chloromethane | 74-87-3 | 3,000 | N | 10,000 | N | 100,000 | N | 900 | N | 4,000 | N | 40,000 | N |
| Chloromethyl Methyl Ether | 107-30-2 | 1 | C | 6 | C | 60 | C | 0.4 | C | 2 | C | 20 | C |
| Chloropicrin | 76-06-2 | 10 | N | 60 | N | 600 | N | 4 | N | 20 | N | 200 | N |
| Cumene | 98-82-8 | 10,000 | N | 60,000 | N | 600,000 | N | 4,000 | N | 20,000 | N | 200,000 | N |
| Cyanide (CN-) | 57-12-5 | 30 | N | 100 | N | 1,000 | N | 8 | N | 40 | N | 400 | N |
| Cyclohexane | 110-82-7 | 200,000 | N | 900,000 | N | 9,000,000 | N | 60,000 | N | 300,000 | N | 3,000,000 | N |
| Cyclohexanone | 108-94-1 | 20,000 | N | 100,000 | N | 1,000,000 | N | 7,000 | N | 30,000 | N | 300,000 | N |
| Cyclohexene | 110-83-8 | 30,000 | N | 100,000 | N | 1,000,000 | N | 10,000 | N | 40,000 | N | 400,000 | N |
| Dibromoethane, 1,2- | 106-93-4 | 2 | C | 7 | C | 70 | C | 0.5 | C | 2 | C | 20 | C |
| Dibromomethane (Methylene Bromide) | 74-95-3 | 100 | N | 600 | N | 6,000 | N | 40 | N | 200 | N | 2,000 | N |
| Dichloro-2-butene, 1,4- | 764-41-0 | 0.2 | C | 1 | C | 10 | C | 0.07 | C | 0.3 | C | 3 | C |
| Dichloro-2-butene, cis-1,4- | 1476-11-5 | 0.2 | C | 1 | C | 10 | C | 0.07 | C | 0.3 | C | 3 | C |
| Dichloro-2-butene, trans-1,4- | 110-57-6 | 0.2 | C | 1 | C | 10 | C | 0.07 | C | 0.3 | C | 3 | C |
| Dichlorobenzene, 1,2- | 95-50-1 | 7,000 | N | 30,000 | N | 300,000 | N | 2,000 | N | 9,000 | N | 90,000 | N |
| Dichlorobenzene, 1,4- | 106-46-7 | 90 | C | 400 | C | 4,000 | C | 30 | C | 100 | C | 1,000 | C |
| Dichlorodifluoromethane | 75-71-8 | 3,000 | N | 10,000 | N | 100,000 | N | 1,000 | N | 4,000 | N | 40,000 | N |
| Dichloroethane, 1,1- | 75-34-3 | 600 | C | 3,000 | C | 30,000 | C | 200 | C | 800 | C | 8,000 | C |
| Dichloroethane, 1,2- | 107-06-2 | 40 | C | 200 | C | 2,000 | C | 10 | C | 50 | C | 500 | C |
| Dichloroethylene, 1,1- | 75-35-4 | 100 | N | 600 | N | 6,000 | N | 40 | N | 200 | N | 2,000 | N |
| Dichloroethylene, cis-1,2- | 156-59-2 | 1,000 | N | 6,000 | N | 60,000 | N | 400 | N | 2,000 | N | 20,000 | N |
| Dichloroethylene, trans-1,2- | 156-60-5 | 1,000 | N | 6,000 | N | 60,000 | N | 400 | N | 2,000 | N | 20,000 | N |
| Dichloropropane, 1,2- | 78-87-5 | 100 | N | 600 | N | 6,000 | N | 40 | N | 200 | N | 2,000 | N |
| Dichloropropene, 1,3- | 542-75-6 | 200 | C | 1,000 | C | 10,000 | C | 70 | C | 300 | C | 3,000 | C |
| Dicyclopentadiene | 77-73-6 | 10 | N | 40 | N | 400 | N | 3 | N | 10 | N | 100 | N |
| Difluoroethane, 1,1- | 75-37-6 | 1,000,000 | N | 6,000,000 | N | 60,000,000 | N | 400,000 | N | 2,000,000 | N | 20,000,000 | N |
| Difluoropropane, 2,2- | 420-45-1 | 1,000,000 | N | 4,000,000 | N | 40,000,000 | N | 300,000 | N | 1,000,000 | N | 10,000,000 | N |
| Diisopropyl Ether | 108-20-3 | 20,000 | N | 100,000 | N | 1,000,000 | N | 7,000 | N | 30,000 | N | 300,000 | N |
| Dimethyl Sulfide | 75-18-3 | 7 | N | 30 | N | 300 | N | 2 | N | 9 | N | 90 | N |
| Dimethylformamide | 68-12-2 | 1,000 | N | 4,000 | N | 40,000 | N | 300 | N | 1,000 | N | 10,000 | N |
| Dimethylhydrazine, 1,1- | 57-14-7 | 0.07 | N | 0.3 | N | 3 | N | 0.02 | N | 0.09 | N | 0.9 | N |
| Dimethylhydrazine, 1,2- | 540-73-8 | 0.006 | C | 0.03 | C | 0.3 | C | 0.002 | C | 0.008 | C | 0.08 | C |
| Dimethylvinylchloride | 513-37-1 | 70 | C | 300 | C | 3,000 | C | 20 | C | 90 | C | 900 | C |
| Dioxane, 1,4- | 123-91-1 | 200 | C | 800 | C | 8,000 | C | 60 | C | 300 | C | 3,000 | C |
| Epichlorohydrin | 106-89-8 | 30 | N | 100 | N | 1,000 | N | 10 | N | 40 | N | 400 | N |
| Epoxybutane, 1,2- | 106-88-7 | 700 | N | 3,000 | N | 30,000 | N | 200 | N | 900 | N | 9,000 | N |
| Ethoxyethanol Acetate, 2- | 111-15-9 | 2,000 | N | 9,000 | N | 90,000 | N | 600 | N | 3,000 | N | 30,000 | N |
| Ethoxyethanol, 2- | 110-80-5 | 1,000 | N | 6,000 | N | 60,000 | N | 400 | N | 2,000 | N | 20,000 | N |
| Ethyl Acetate | 141-78-6 | 2,000 | N | 10,000 | N | 100,000 | N | 700 | N | 3,000 | N | 30,000 | N |
| Ethyl Acrylate | 140-88-5 | 300 | N | 1,000 | N | 10,000 | N | 80 | N | 400 | N | 4,000 | N |
| Ethyl Chloride (Chloroethane) | 75-00-3 | 100,000 | N | 600,000 | N | 6,000,000 | N | 40,000 | N | 200,000 | N | 2,000,000 | N |
| Ethyl Methacrylate | 97-63-2 | 10,000 | N | 40,000 | N | 400,000 | N | 3,000 | N | 10,000 | N | 100,000 | N |
| Ethyl Tertiary Butyl Ether (ETBE) | 637-92-3 | 10,000 | C | 50,000 | C | 500,000 | C | 4,000 | C | 20,000 | C | 200,000 | C |
| Ethylbenzene | 100-41-4 | 400 | C | 2,000 | C | 20,000 | C | 100 | C | 500 | C | 5,000 | C |
| Ethylene Oxide | 75-21-8 | 0.1 | C | 1 | C | 10 | C | 0.03 | C | 0.4 | C | 4 | C |
| Ethyleneimine | 151-56-4 | 0.05 | C | 0.2 | C | 2 | C | 0.02 | C | 0.07 | C | 0.7 | C |
| Formaldehyde | 50-00-0 | 50 | C | 600 | C | 6,000 | C | 10 | C | 200 | C | 2,000 | C |
| Formic Acid | 64-18-6 | 10 | N | 40 | N | 400 | N | 3 | N | 10 | N | 100 | N |
| Furfural | 98-01-1 | 2,000 | N | 7,000 | N | 70,000 | N | 500 | N | 2,000 | N | 20,000 | N |
| Glycidaldehyde | 765-34-4 | 30 | N | 100 | N | 1,000 | N | 10 | N | 40 | N | 400 | N |
| Heptanal, n- | 111-71-7 | 100 | N | 400 | N | 4,000 | N | 30 | N | 100 | N | 1,000 | N |
| Heptane, N- | 142-82-5 | 10,000 | N | 60,000 | N | 600,000 | N | 4,000 | N | 20,000 | N | 200,000 | N |
| Hexane, Commercial | E5241997 | 5,000 | C | 20,000 | C | 200,000 | C | 1,000 | C | 6,000 | C | 60,000 | C |
| Hexane, N- | 110-54-3 | 20,000 | N | 100,000 | N | 1,000,000 | N | 7,000 | N | 30,000 | N | 300,000 | N |
| Hexanone, 2- | 591-78-6 | 1,000 | N | 4,000 | N | 40,000 | N | 300 | N | 1,000 | N | 10,000 | N |
| Hydrazine | 302-01-2 | 0.2 | C | 0.8 | C | 8 | C | 0.06 | C | 0.3 | C | 3 | C |
| Hydrogen Chloride | 7647-01-0 | 700 | N | 3,000 | N | 30,000 | N | 200 | N | 900 | N | 9,000 | N |
| Hydrogen Cyanide | 74-90-8 | 30 | N | 100 | N | 1,000 | N | 8 | N | 40 | N | 400 | N |
| Hydrogen Fluoride | 7664-39-3 | 500 | N | 2,000 | N | 20,000 | N | 200 | N | 600 | N | 6,000 | N |
| Hydrogen Sulfide | 7783-06-4 | 70 | N | 300 | N | 3,000 | N | 20 | N | 90 | N | 900 | N |
| Isobutyl Alcohol | 78-83-1 | 10,000 | N | 60,000 | N | 600,000 | N | 4,000 | N | 20,000 | N | 200,000 | N |
| Isopropanol | 67-63-0 | 7,000 | N | 30,000 | N | 300,000 | N | 2,000 | N | 9,000 | N | 90,000 | N |
| Isopropyltoluene, p- | 99-87-6 | 1,000 | N | 6,000 | N | 60,000 | N | 400 | N | 2,000 | N | 20,000 | N |
| Jet propulsion fuel 7 (JP-7) | E1737665 | 10,000 | N | 40,000 | N | 400,000 | N | 3,000 | N | 10,000 | N | 100,000 | N |
| Methacrylonitrile | 126-98-7 | 1,000 | N | 4,000 | N | 40,000 | N | 300 | N | 1,000 | N | 10,000 | N |
| Methanol | 67-56-1 | 700,000 | N | 3,000,000 | N | 30,000,000 | N | 200,000 | N | 900,000 | N | 9,000,000 | N |
| Methoxyethanol Acetate, 2- | 110-49-6 | 30 | N | 100 | N | 1,000 | N | 10 | N | 40 | N | 400 | N |
| Methoxyethanol, 2- | 109-86-4 | 200 | N | 1,000 | N | 10,000 | N | 70 | N | 300 | N | 3,000 | N |
| Methyl Acrylate | 96-33-3 | 700 | N | 3,000 | N | 30,000 | N | 200 | N | 900 | N | 9,000 | N |
| Methyl Ethyl Ketone (2-Butanone) | 78-93-3 | 200,000 | N | 700,000 | N | 7,000,000 | N | 50,000 | N | 200,000 | N | 2,000,000 | N |
| Methyl Hydrazine | 60-34-4 | 0.7 | N | 3 | N | 30 | N | 0.2 | N | 0.9 | N | 9 | N |
| Methyl Isobutyl Ketone (4-methyl-2-pentanone) | 108-10-1 | 100,000 | N | 400,000 | N | 4,000,000 | N | 30,000 | N | 100,000 | N | 1,000,000 | N |
| Methyl Isocyanate | 624-83-9 | 30 | N | 100 | N | 1,000 | N | 10 | N | 40 | N | 400 | N |
| Methyl Methacrylate | 80-62-6 | 20,000 | N | 100,000 | N | 1,000,000 | N | 7,000 | N | 30,000 | N | 300,000 | N |
| Methyl Styrene (Mixed Isomers) | 25013-15-4 | 1,000 | N | 6,000 | N | 60,000 | N | 400 | N | 2,000 | N | 20,000 | N |
| Methyl tert-Butyl Ether (MTBE) | 1634-04-4 | 4,000 | C | 20,000 | C | 200,000 | C | 1,000 | C | 5,000 | C | 50,000 | C |
| Methyl-2-Pentanol, 4- | 108-11-2 | 100,000 | N | 400,000 | N | 4,000,000 | N | 30,000 | N | 100,000 | N | 1,000,000 | N |
| Methylcyclohexane | 108-87-2 | 3,000 | N | 10,000 | N | 100,000 | N | 1,000 | N | 4,000 | N | 40,000 | N |
| Methylene Chloride | 75-09-2 | 20,000 | N | 90,000 | N | 900,000 | N | 6,000 | N | 30,000 | N | 300,000 | N |
| Nickel Carbonyl | 13463-39-3 | 0.5 | N | 2 | N | 20 | N | 0.2 | N | 0.6 | N | 6 | N |
| Nitromethane | 75-52-5 | 100 | C | 500 | C | 5,000 | C | 30 | C | 100 | C | 1,000 | C |
| Nitropropane, 2- | 79-46-9 | 2 | C | 7 | C | 70 | C | 0.5 | C | 2 | C | 20 | C |
| Nitrosodimethylamine, N- | 62-75-9 | 0.02 | C | 0.3 | C | 3 | C | 0.007 | C | 0.09 | C | 0.9 | C |
| Nitrosomethylethylamine, N- | 10595-95-6 | 0.2 | C | 0.6 | C | 6 | C | 0.05 | C | 0.2 | C | 2 | C |
| Nonane, n- | 111-84-2 | 700 | N | 3,000 | N | 30,000 | N | 200 | N | 900 | N | 9,000 | N |
| Pentane, n- | 109-66-0 | 30,000 | N | 100,000 | N | 1,000,000 | N | 10,000 | N | 40,000 | N | 400,000 | N |
| Phosgene | 75-44-5 | 10 | N | 40 | N | 400 | N | 3 | N | 10 | N | 100 | N |
| Phosphine | 7803-51-2 | 10 | N | 40 | N | 400 | N | 3 | N | 10 | N | 100 | N |
| Propionaldehyde | 123-38-6 | 300 | N | 1,000 | N | 10,000 | N | 80 | N | 400 | N | 4,000 | N |
| Propyl benzene | 103-65-1 | 30,000 | N | 100,000 | N | 1,000,000 | N | 10,000 | N | 40,000 | N | 400,000 | N |
| Propylene | 115-07-1 | 100,000 | N | 400,000 | N | 4,000,000 | N | 30,000 | N | 100,000 | N | 1,000,000 | N |
| Propylene Glycol Monomethyl Ether | 107-98-2 | 70,000 | N | 300,000 | N | 3,000,000 | N | 20,000 | N | 90,000 | N | 900,000 | N |
| Propylene Oxide | 75-56-9 | 300 | C | 1,000 | C | 10,000 | C | 80 | C | 300 | C | 3,000 | C |
| Styrene | 100-42-5 | 30,000 | N | 100,000 | N | 1,000,000 | N | 10,000 | N | 40,000 | N | 400,000 | N |
| Sulfur Trioxide | 7446-11-9 | 30 | N | 100 | N | 1,000 | N | 10 | N | 40 | N | 400 | N |
| Tert-Butyl Acetate | 540-88-5 | 700 | C | 3,000 | C | 30,000 | C | 200 | C | 900 | C | 9,000 | C |
| Tetrachloroethane, 1,1,1,2- | 630-20-6 | 100 | C | 600 | C | 6,000 | C | 40 | C | 200 | C | 2,000 | C |
| Tetrachloroethane, 1,1,2,2- | 79-34-5 | 20 | C | 70 | C | 700 | C | 5 | C | 20 | C | 200 | C |
| Tetrachloroethylene | 127-18-4 | 1,000 | N | 6,000 | N | 60,000 | N | 400 | N | 2,000 | N | 20,000 | N |
| Tetrafluoroethane, 1,1,1,2- | 811-97-2 | 3,000,000 | N | 10,000,000 | N | 100,000,000 | N | 800,000 | N | 4,000,000 | N | 40,000,000 | N |
| Tetrahydrofuran | 109-99-9 | 70,000 | N | 300,000 | N | 3,000,000 | N | 20,000 | N | 90,000 | N | 900,000 | N |
| Titanium Tetrachloride | 7550-45-0 | 3 | N | 10 | N | 100 | N | 1 | N | 4 | N | 40 | N |
| Toluene | 108-88-3 | 200,000 | N | 700,000 | N | 7,000,000 | N | 50,000 | N | 200,000 | N | 2,000,000 | N |
| Trichloro-1,2,2-trifluoroethane, 1,1,2- | 76-13-1 | 200,000 | N | 700,000 | N | 7,000,000 | N | 50,000 | N | 200,000 | N | 2,000,000 | N |
| Trichloroethane, 1,1,1- | 71-55-6 | 200,000 | N | 700,000 | N | 7,000,000 | N | 50,000 | N | 200,000 | N | 2,000,000 | N |
| Trichloroethane, 1,1,2- | 79-00-5 | 7 | N | 30 | N | 300 | N | 2 | N | 9 | N | 90 | N |
| Trichloroethylene | 79-01-6 | 70 | N | 300 | N | 3,000 | N | 20 | N | 90 | N | 900 | N |
| Trichloropropane, 1,2,3- | 96-18-4 | 10 | N | 40 | N | 400 | N | 3 | N | 10 | N | 100 | N |
| Trichloropropene, 1,2,3- | 96-19-5 | 10 | N | 40 | N | 400 | N | 3 | N | 10 | N | 100 | N |
| Triethylamine | 121-44-8 | 200 | N | 1,000 | N | 10,000 | N | 70 | N | 300 | N | 3,000 | N |
| Trifluoroethane, 1,1,1- | 420-46-2 | 700,000 | N | 3,000,000 | N | 30,000,000 | N | 200,000 | N | 900,000 | N | 9,000,000 | N |
| Trimethylbenzene, 1,2,3- | 526-73-8 | 2,000 | N | 9,000 | N | 90,000 | N | 600 | N | 3,000 | N | 30,000 | N |
| Trimethylbenzene, 1,2,4- | 95-63-6 | 2,000 | N | 9,000 | N | 90,000 | N | 600 | N | 3,000 | N | 30,000 | N |
| Trimethylbenzene, 1,3,5- | 108-67-8 | 2,000 | N | 9,000 | N | 90,000 | N | 600 | N | 3,000 | N | 30,000 | N |
| Vinyl Acetate | 108-05-4 | 7,000 | N | 30,000 | N | 300,000 | N | 2,000 | N | 9,000 | N | 90,000 | N |
| Vinyl Bromide | 593-60-2 | 60 | C | 300 | C | 3,000 | C | 20 | C | 80 | C | 800 | C |
| Vinyl Chloride | 75-01-4 | 60 | C | 900 | C | 9,000 | C | 20 | C | 300 | C | 3,000 | C |
| Xylenes | 1330-20-7 | 3,000 | N | 10,000 | N | 100,000 | N | 1,000 | N | 4,000 | N | 40,000 | N |
No results found.
Practical Notes
Choosing the right column: Match the column to your sampling location and the building type at or nearest to the sample location:
- Sub-slab probes or exterior probes deeper than 5 feet: use the Sub/Deep columns
- Exterior probes within 5 feet of grade: use the Shallow columns
- Residential buildings, apartments, schools: use the Res columns
- Commercial buildings: use the Com columns
- Large commercial or industrial buildings (qualifying under the R2’s lines of evidence - thick foundations, high ceilings and volumes, high air exchange): use the LgCom columns
Soil gas sampling methods: IDEM guidance references EPA’s Vapor Intrusion Technical Guide and ITRC guidance documents for soil gas sampling methodology. Proper probe installation, purging, leak testing, and sample collection are critical to obtaining representative results. A soil gas sample with a leak will underestimate concentrations and produce a false negative.
Indoor air vs. soil gas: When both indoor air and soil gas data are available, compare each to the appropriate published level. An exceedance of the soil gas level alone does not mean indoor air is impacted - building characteristics, HVAC systems, and seasonal variation affect actual indoor air concentrations. Conversely, indoor air may be impacted even if soil gas is below the screening level if other sources of VOC vapors exist in or near the building.
Relationship to indoor air levels: The soil gas screening levels on this page are mathematically derived from the Indiana Indoor Air Published Levels - VOCs. If soil gas results are below the screening level for the applicable scenario, indoor air concentrations are expected to be below the indoor air published level assuming IDEM’s standard attenuation factors. Site-specific conditions may warrant a more detailed evaluation.