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Risk Assessment

Regional Screening Levels (RSLs) - Equations

 

The Regional Screening Level (RSL) Equations Page provides quick access to the equations used in chemical risk assessments. The equations contain the defaults for the exposure parameters.

For assistance/questions please use the Regional Screening Levels (RSLs) contact us page.

 



 
  • Resident

    Resident Soil

    This land use is for developing residential default screening levels that are presented in the RSL Generic Tables.

    • Noncarcinogenic-child
      • IngestionResident Soil Equations - Noncarcinogenic-child - Ingestion Equation
      • DermalResident Soil - Noncarcinogenic-child - Dermal Equation
      • InhalationResident Soil - Noncarcinogenic-child - Inhalation Equation
      • TotalResident Soil - Noncarcinogenic-child - Total Equation
         
    • Noncarcinogenic-adult
      • IngestionResident Soil - Noncarcinogenic-adult - Ingestion Equation
      • DermalResident Soil  - Noncarcinogenic-adult - Dermal Equation
      • InhalationResident Soil - Noncarcinogenic-adult - Inhalation Equation
      • TotalResident Soil - Noncarcinogenic-adult - Total Equation
         
    • Carcinogenic
      • IngestionResident Soil - Carcinogenic - Ingestion Equation
      • DermalResident Soil - Carcinogenic - Dermal Equation
      • InhalationResident Soil - Carcinogenic - Inhalation Equation
      • TotalResident Soil - Carcinogenic - Total Equation
         
    • Mutagenic
      • Ingestion
        Resident Soil Equation - Mutagenic - Ingestion
      • Dermal
        Resident Soil - Mutagenic - Dermal Equation
      • InhalationResident Soil - Mutagenic - Inhalation Equation
      • TotalResident Soil - Mutagenic - Total Equation
         
    • Vinyl Chloride
      • Ingestion
        Resident Soil - Vinyl Chloride - Ingestion Equation
      • Dermal
        Resident Soil - Vinyl Chloride - Dermal Equation
      • InhalationResident Soil - Vinyl Chloride - Inhalation Equation
      • TotalResident Soil - Vinyl Chloride - Total Equation
         
    • Trichloroethylene
      • IngestionResident Soil - Trichloroethylene - Ingestion Equation
      • Dermal
        Resident Soil Equation - Trichloroethylene - Dermal
      • InhalationResident Soil Equation - Trichloroethylene - Inhalation
      • TotalResident Soil Equation - Trichloroethylene - Total
    • Supporting Equations
      • ChildResident Soil Equation - Supporting Equations - Child
      • AdultResident Soil Equation - Supporting Equations - Adult
      • Age-adjustedResident Soil Equation - Supporting Equations - Age-adjusted

    Resident Tapwater

    This land use is for developing residential default screening levels that are presented in the RSL Generic Tables.

    • Noncarcinogenic-child
      • IngestionResidential tapwater noncarcinogenic ingestion child screening level
      • DermalResidential tapwater noncarcinogenic dermal child screening level
      • InhalationResidential tapwater noncarcinogenic inhalation child screening level
      • TotalResidential tapwater noncarcinogenic total child screening level
    • Noncarcinogenic-adult
      • IngestionResidential tapwater noncarcinogenic ingestion adult screening level
      • DermalResidential tapwater noncarcinogenic dermal adult screening level
      • InhalationResidential tapwater noncarcinogenic inhalation adult screening level
      • TotalResident tapwater noncarcinogenic total adult screening level
    • Carcinogenic
      • IngestionResident tapwater cancer ingestion screening level
      • DermalResident tapwater cancer dermal screening level
      • InhalationResident tapwater cancer inhalation screening level
      • TotalResident tapwater cancer total screening level
    • Mutagenic
      • IngestionResident tapwater mutagen ingestion screening level
      • DermalResident tapwater mutagen dermal screening level
      • InhalationResident tapwater mutagen inhalation screening level
      • TotalResident tapwater mutagen total screening level
    • Vinyl Chloride
      • IngestionResident tapwater vinyl chloride ingestion screening level
      • DermalResident tapwater vinyl chloride dermal screening level
      • InhalationResident tapwater vinyl chloride inhalation screening level
      • TotalResident tapwater vinyl chloride total screening level
    • Trichloroethylene
      • IngestionResident tapwater trichloroethylene ingestion screening level
      • DermalResident tapwater trichloroethylene dermal screening level
      • InhalationResident tapwater trichloroethylene inhalation screening level
      • TotalResident tapwater trichloroethylene total screening level
    • Supporting Equations
      • Child
        Tap Water Equations - Supporting Equations - Child
      • Adult
        Tap Water Equations - Supporting Equations - Adult
      • Age-adjustedTap Water Equations - Supporting Equations - Age-adjusted

    Resident Air

    This land use is for developing residential default screening levels that are presented in the RSL Generic Tables.

    • Noncarcinogenic
      • InhalationResident Air Equation - Noncarcinogenic - Inhalation
    • Carcinogenic
      • InhalationResident Air Equation - Carcinogenic - Inhalation
    •  Mutagenic
      • Inhalation
    Resident Air Equation - Mutagenic - Inhalation
    • Vinyl Chloride
      • InhalationResident Air Vinyl Chloride inhalation screening level
    • Trichloroethylene
      • Inhalation
        Resident Air Equation - Trichloroethylene - Inhalation
  • Composite Worker

    Composite Worker Soil

    This land use is for developing industrial default screening levels that are presented in the RSL Generic Tables.

    • Noncarcinogenic
      • Ingestion
        Composite Worker Soil Equation - Noncarcinogenic - Ingestion
      • Dermal
        Composite Worker Soil Equation - Noncarcinogenic - Dermal
      • InhalationComposite Worker Soil Equation - Non-cancer - Inhalation
      • TotalComposite Worker Soil Equation - Noncarcinogenic - Total
         
    • Carcinogenic
      • Ingestion
        Composite Worker Soil Equation - Carcinogenic - Ingestion
      • Dermal
        Composite Worker Soil Equation - Carcinogenic - Dermal
      • InhalationComposite Worker Soil Equation - Carcinogen - Inhalation
      • TotalComposite Worker Soil Equation - Carcinogenic - Total

    Composite Worker Air

    This land use is for developing industrial default screening levels that are presented in the RSL Generic Tables.

    • Noncarcinogenic
      The air land use equation, presented here, contains the following exposure routes:
      • Inhalation
        Worker Air Equation - Noncarcinogenic - Inhalation
    • Carcinogenic
      The air land use equation, presented here, contains the following exposure routes:
      • Inhalation
        Worker Air Equation - Carcinogenic - Inhalation
  • Outdoor Worker

    Outdoor Worker Soil

    The outdoor worker soil land use is not provided in the RSL Generic Tables but RSLs can be created by using the Calculator.

    • Noncarcinogenic
      • Ingestion
        Outdoor Worker Soil Equations - Noncarcinogenic - Ingestion
      • Dermal
        Outdoor Worker Soil Equations - Noncarcinogenic - Dermal
      • InhalationOutdoor Worker Soil Equation - Noncarcinogenic - Inhalation
      • TotalOutdoor Worker Soil Equation - Noncarcinogenic - Total
    • Carcinogenic
      • Ingestion
        Outdoor Worker Soil Equation - Carcinogenic - Ingestion
      • Dermal
        Outdoor Worker Soil Equation - Carcinogenic - Dermal
      • InhalationOutdoor Worker Soil Equation - carcinogenic - Inhalation
      • TotalOutdoor Worker Soil Equation - Carcinogenic - Total

    Outdoor Worker Air

    The outdoor worker air land use is not provided in the RSL Generic Tables but RSLs can be created by using the Calculator.

    • Noncarcinogenic
      The air land use equation, presented here, contains the following exposure routes:
      • InhalationOutdoor worker air noncarcinogenic equation
    • Carcinogenic
      The air land use equation, presented here, contains the following exposure routes:
      • InhalationOutdoor worker air carcinogenic equation
  • Indoor Worker

    Indoor Worker Soil

    The indoor worker soil land use is not provided in the Generic Tables but RSLs can be created by using the Calculator.

    • Noncarcinogenic
      • Ingestion
        Indoor Worker Soil Equation - Noncarcinogenic - Ingestion
      • InhalationIndoor Worker Soil Equation - noncarcinogenic - Inhalation
      • TotalIndoor Worker Soil Equation - Noncarcinogenic - Total
    • Carcinogenic
      • Ingestion
        Indoor Worker Soil Equation - Carcinogenic - Ingestion
      • InhalationIndoor Worker Soil Equation - carcinogenic - Inhalation
      • TotalIndoor Worker Soil Equation - Carcinogenic - Total

    Indoor Worker Air

    The indoor worker air land use is not provided in the RSL Generic Tables but RSLs can be created by using the Calculator.

    Noncarcinogenic
    The air land use equation, presented here, contains the following exposure routes:

    • Inhalation
    Indoor worker air noncarcinogenic inhalation equation
    Carcinogenic
    The air land use equation, presented here, contains the following exposure routes:
    • InhalationIndoor worker air carcinogenic inhalation equation
  • Construction Worker

    Construction Worker Soil Exposure for Standard Vehicle Traffic

    The construction worker soil land use is not provided in the Generic Tables but RSLs can be created by using the Calculator.

    • Noncarcinogenic
      • Ingestion
        Construction Worker Soil Equation for Standard Vehicle Traffic - Noncarcinogenic - Ingestion
      • Dermal
        Construction Worker Soil Equation for Standard Vehicle Traffic - Noncarcinogenic - Dermal
      • InhalationConstruction Worker Standard Vehicle Soil Equation - noncarcinogenic - Inhalation
      • TotalConstruction Worker Soil Equation for Standard Vehicle Traffic - Noncarcinogenic - Total
    • Carcinogenic
      • Ingestion
        Construction Worker Soil Equation for Standard Vehicle Traffic - Carcinogenic - Ingestion
      • Dermal
        Construction Worker Soil Equation for Standard Vehicle Traffic - Carcinogenic - Dermal
      • InhalationConstruction Worker Standard Vehicle Soil Equation - carcinogenic - Inhalation
      • TotalConstruction Worker Soil Equation for Standard Vehicle Traffic - Carcinogenic - Total

    Construction Worker Soil Exposure for Other Construction Activities

    The construction worker soil land use is not provided in the Generic Tables but RSLs can be created by using the Calculator.

    • Noncarcinogenic
      • IngestionConstruction Worker Soil Equation for Other than Standard Vehicle Traffic - Noncarcinogenic - Ingestion
      • DermalConstruction Worker Soil Equation for Other than Standard Vehicle Traffic - Noncarcinogenic - Dermal
      • InhalationConstruction Worker Other Activities Soil Equation - noncarcinogenic - Inhalation
      • TotalConstruction Worker Soil Equation for Other than Standard Vehicle Traffic - Noncarcinogenic - Total
    • Carcinogenic
      • Ingestion
        Construction Worker Soil Equation for Other than Standard Vehicle Traffic - Carcinogenic - Ingestion
      • Dermal
        Construction Worker Soil Equation for Other than Standard Vehicle Traffic - Carcinogenic - Dermal
      • InhalationConstruction Worker Other Activities Soil Equation - carcinogenic - Inhalation
      • TotalConstruction Worker Soil Equation for Other than Standard Vehicle Traffic - Carcinogenic - Total
  • Recreator

    Recreator Soil/Sediment

    The recreator soil land use is not provided in the Generic Tables but RSLs can be created by using the Calculator.

    • Noncarcinogenic - Child
      • IngestionRecreational Soil/Sediment Equation - Noncarcinogenic - Child - Ingestion
      • DermalRecreational Soil/Sediment Equation - Noncarcinogenic - Child - Dermal
      • InhalationRecreator Child Soil Equation - noncarcinogenic - Inhalation
      • TotalRecreational Soil/Sediment Equation - Noncarcinogenic - Child - Total
         
    • Noncarcinogenic - Adult
      • IngestionRecreational Soil/Sediment Equation - Noncarcinogenic - Adult - Ingestion
      • DermalRecreational Soil/Sediment Equation - Noncarcinogenic - Adult - Dermal
      • InhalationRecreator Adult Soil Equation - noncarcinogenic - Inhalation
      • TotalRecreational Soil/Sediment Equation - Noncarcinogenic - Adult - Total
         
    • Carcinogenic
      • IngestionRecreational Soil/Sediment Equation - Carcinogenic - Ingestion
      • DermalRecreational Soil/Sediment Equation - Carcinogenic - Dermal
      • InhalationRecreator Soil Equation - carcinogenic - Inhalation
      • TotalRecreational Soil/Sediment Equation - Carcinogenic - Total
    • Mutagenic
      • Ingestion
        Recreational Soil/Sediment Equation - Mutagenic - Ingestion
      • Dermal
        Recreational Soil/Sediment Equation - Mutagenic - Dermal
      • InhalationRecreator Soil Equation - mutagenic - Inhalation
      • TotalRecreational Soil/Sediment Equation - Mutagenic - Total
    • Vinyl Chloride
      • Ingestion
        Recreational Soil/Sediment Equation - Vinyl Chloride - Ingestion
      • DermalRecreational Soil/Sediment Equation - Vinyl Chloride - Dermal
      • InhalationRecreator Soil Equation - vinyl chloride - Inhalation
      • TotalRecreational Soil/Sediment Equation - Vinyl Chloride - Total
    • Trichloroethylene
      • Ingestion
        Recreational Soil/Sediment Equation - Trichloroethylene - Ingestion
      • Dermal
        Recreational Soil/Sediment Equation - Trichloroethylene - Dermal
      • InhalationRecreator Soil Equation - trichloroethylene - Inhalation
      • TotalRecreational Soil/Sediment Equation - Trichloroethylene - Total
         
    • Supporting Equations
      • ChildRecreational Soil/Sediment Equation - Supporting Equations - Child
      • Adult
        Recreational Soil/Sediment Equation - Supporting Equations - Adult
      • Age-adjustedRecreational Soil/Sediment Equation - Supporting Equations - Age-adjusted

    Recreator Surface Water

    The recreator surface water land use is not provided in the Generic Tables but RSLs can be created by using the Calculator.

    • Noncarcinogenic - Child
      • Ingestion
        srst_rec_wat_nc_ing_child.gif
      • DermalRecreator Surface Water noncancer dermal screening level
      • TotalRecreator Surface Water Equation - Noncarcinogenic - Child - Total
    • Noncarcinogenic - Adult
      • Ingestion
      • DermalRecreator Surface Water noncancer dermal adult screening level
      • TotalRecreator Surface Water noncancer total adult screening level
    • Carcinogenic
      • Ingestion
      • DermalRecreator Surface Water cancer dermal screening level
      • TotalRecreator Surface Water cancer total screening level
    • Mutagenic
      • IngestionRecreator Surface Water mutagen ingestion screening level
      • DermalRecreator Surface Water mutagen dermal screening level
      • TotalRecreator Surface Water mutagen total screening level
    • Vinyl Chloride
      • Ingestion
      • Dermal
      • TotalRecreator Surface Water Vinyl Chloride total screening level
    • Trichloroethylene
      • Ingestion
      • DermalRecreator Surface Water Trichloroethylene dermal screening level
      • TotalRecreator Surface Water Trichloroethylene total screening level
    • Supporting Equations
      • ChildRecreator Surface Water Equation - Supporting Equations - Child
      • AdultRecreator Surface Water Equation - Supporting Equations - Adult
  • Fish Ingestion

    The ingestion of fish land use is not provided in the Generic Tables but RSLs can be created by using the Calculator.

    • Noncarcinogenic
      Fish Ingestion Equation - Noncarcinogenic
    • Carcinogenic
      Fish Ingestion Equation - Carcinogenic
  • Soil to Groundwater

    This land use is for developing default soil screening levels for the protection of groundwater that are presented in the RSL Generic Tables.

    • Method 1
      Soil to Ground Water Equation - Method 1
    • Method 2
      Soil to Groundwater Method #2
    • Dilution Factor
      Soil to Ground Water Equation - Dilution Factor
  • Supporting Equations
    • Wind Particulate Emission Factor pef.gif
    • Mechanical Particulate Emission Factor for Construction Worker from Vehicle Traffic on Unpaved RoadsSupporting Equation - Mechanical Particulate Emission Factor for Construction Worker from Vehicle Traffic on Unpaved  Roads
    • Mechanical Particulate Emission Factor for Construction Worker from other than Vehicle Traffic on Unpaved RoadSupporting Equation - Mechanical Particulate Emission Factor for Construction Worker from other than Vehicle Traffic on   Unpaved Roads
    • Wind Volatilization FactorsSupporting Equation - Wind Volatilization Factors
    • Diffusivity in WaterSupporting Equation - Wind Volatilization Factors 2
    • Diffusivity in AirSupporting Equation - Diffusivity in Air
    • Mass Limit Volatilization FactorSupporting Equation - Wind Volatilization Factors 4
    • Unlimited Source Subchronic Volatilization Factor for Construction WorkerSupporting Equation - Unlimited Source Subchronic Volatilization Factor for Construction Worker
    • Mass Limit Subchronic Volatilization Factor for Construction WorkerSupporting Equation - Mass Limit Subchronic Volatilization Factor for Construction Worker
    • Dermal Contact with Water Supporting Equations
    • BDermal Contact Equation
    • TauSupporting Equation - Dermal Contact with Water Supporting Equation 2
    • t*Supporting Equation - Dermal Contact with Water Supporting Equation 3
    • Soil Saturation LimitSupporting Equation - Soil Saturation Limit
    • TCE Toxicity Adjustment FactorsSupporting Equation - TCE Toxicity Adjustment Factors

For assistance/questions please use the Regional Screening Levels (RSLs) contact us page. For general risk assessment questions, separate from the RSLs, please use the link below.