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  2. Vapor Intrusion

VISL Equations

Vapor Intrusion Screening Levels (VISLs)
  • VISL Home
  • User's Guide
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  • Equations
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On this page:

  • Resident Air Screening Level
  • Worker Air Screening Level
  • Groundwater Screening Level
  • Soil Gas Screening Level
  • Vapor Intrusion Screening Level Supporting Equations
  • Indoor Air Concentration Derived from Soil Gas Concentration
  • Indoor Air Concentration Derived from Groundwater Concentration
  • Calculation of Risks and Hazards from Indoor Air Concentrations
  • Resident Air Chronic Daily Intakes (CDI)
  • Worker Air Chronic Daily Intakes (CDI)
  • Using Unit's in ppb
  • Modifications of Groundwater Temperatures

Resident Air Screening Level

Noncarcinogenic

Inhalation

VISL Resident Air Noncarcinogenic

Carcinogenic

Inhalation

Mutagenic

Inhalation

VISL Resident Air Mutagenic

Vinyl Chloride

Inhalation

VISL Resident Air Vinyl Chloride

Trichloroethylene

Inhalation

  • Trichloroethylene Supporting Equation

Worker Air Screening Level

Noncarcinogenic

Inhalation

Carcinogenic

Inhalation

Groundwater Screening Level

Soil Gas Screening Level

Vapor Intrusion Screening Level Supporting Equations

  • Pure Phase Vapor Concentration
  • Groundwater Vapor Concentration

Indoor Air Concentration Derived from Soil Gas Concentration

  • Calculated Indoor Air Concentration from Soil Gas

Indoor Air Concentration Derived from Groundwater Concentration

  • Calculated Indoor Air Concentration from Groundwater

Calculation of Risks and Hazards from Indoor Air Concentrations

  • Excess Lifetime Cancer Risk
  • Hazard Quotient

Resident Air Chronic Daily Intakes (CDI)

Noncarcinogenic

Carcinogenic

Mutagenic

Vinyl Chloride

Trichloroethylene

  • Trichloroethylene Supporting Equation

Worker Air Chronic Daily Intakes (CDI)

Noncarcinogenic

Carcinogenic

Using Units in ppb

  • ppb Unit Conversion

Modifications of Groundwater Temperatures

To Determine Unitless Henry's Law Constant at a Groundwater Temperature of 25° Celsius

To Determine Unitless Henry's Law Constant at a Groundwater Temperature other than 25° Celsius

To Determine Vapor Pressure at a Groundwater Temperature other than 25° Celsius

To Determine Pure Phase Vapor Concentration at a Groundwater Temperature other than 25° Celsius

Vapor Intrusion

  • About Vapor Intrusion
  • Vapor Intrusion at Superfund Sites
  • Resources
  • Vapor Intrusion Database
Contact Us About Vapor Intrusion
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on September 13, 2024
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