Vapor Intrusion Pathway: Investigative Approaches for Typical Scenarios (VI-1A) (Supplement to VI-1)

NOTE: The ITRC Vapor Intrusion Toolkit (VI Toolkit) published in January 2026 updates the information in this original guidance document. This document has not been amended since publication. Some content may be out of date and may no longer apply. For the most recent information, please visit the ITRC VI Toolkit at https://itrcweb.org/vapor-intrusion-toolkit/.

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Describes applicable approaches for evaluating the vapor intrusion pathway in six typical scenarios.

See also ITRC’s Petroleum Vapor Intrusion (PVI-1) Oct-14 , specifically Appendix G. Investigation Methods and Analysis Toolbox and Appendix J. Vapor Intrusion Control that provides updated information for all type of vapor intrusion investigations.

• VI-1A
• ITRC Petroleum Vapor Intrusion (PVI-1)

Topic(s): Petroleum Hydrocarbons, Vapor Intrusion