The What's New section keeps users informed of changes to: toxicity values, exposure parameters, chemical-specific parameters, equation formats, and any other changes to the VISL calculator. Please check this site frequently to be advised of any recent changes.

May 18, 2020

The toxicity values and physiochemical parameters have been updated. To see what updates have occurred, check the RSL What's New page.

November 18, 2019

The toxicity values and physiochemical parameters have been updated. To see what updates have occurred, check the RSL What's New page.

May 16, 2019

The toxicity values and physiochemical parameters have been updated. To see what updates have occurred, check the RSL What's New page.

The equation labels for pure phase vapor concentration at standard temperature and other than standard temperature have been changed to be more clear and offer greater differentiation between the new equations that display how vapor pressure is changed by a changing groundwater-soil system temperature. The User's Guide in section 2.4, 4.2, and Table 1 have been updated. The Equations page has also been updated.

November 19, 2018

The toxicity values and physiochemical parameters have been updated. To see what updates have occurred, check the RSL What's New page.

May 15, 2018

The toxicity values and physiochemical parameters have been updated. To see what updates have occurred, check the RSL What's New page.

February 2018

The Vapor Intrusion Screening Level (VISL) calculator is now available as an online calculator, replacing previous versions in MS-Excel workbooks. The VISL now uses the same database as the Regional Screening Levels (RSLs) for toxicity values and physiochemical parameters and will be automatically updated during the semi-annual RSL updates.