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 Some content may be out of date and may no longer apply.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/.
This guidance document provides an eight-step process for the effective assessment and management of vapor intrusion at sites contaminated with petroleum hydrocarbons. The guidance includes screening tools and evaluation strategies with a focus on the principal of vertical separation distance.
Two checklists are included to use in conjunction with the eight-step process to organize and document decisions; one for a single site and one for multiple sites.
Topic(s): Petroleum Hydrocarbons, Site Characterization, Vapor Intrusion
