Note: The Vapor Intrusion Toolkit (VIT-1, 2026) published in January 2026 updates the information in this original guidance document. This document has remained unchanged since publication. Some content may be out of date and may no longer apply. For the most recent information, please visit the Vapor Intrusion Toolkit at https://itrcweb.org/vapor-intrusion-toolkit/.
State environmental agencies across the country have consistently listed vapor intrusion as a high priority topic for sites contaminated with volatile organic compounds. This broad group of organic chemicals includes chlorinated compounds, as well as non-chlorinated compounds such as petroleum hydrocarbons. When contaminant vapors from contaminated soil and groundwater migrate upward into overlying buildings and contaminate indoor air, the process is known as vapor intrusion. The results of vapor intrusion can negatively affect the health of building inhabitants.
Petroleum Vapor Intrusion: Fundamentals of Screening, Investigation, and Management (PVI-1, 2014) provides guidance on how to assess and manage petroleum vapor intrusion (PVI) at sites contaminated with petroleum hydrocarbons. The document presents an eight-step process that uses screening tools, evaluation strategies, and the principle of vertical separation distance to help determine when additional investigation may be needed. The guidance includes two checklists to help users organize and document decisions, one for managing a single site and another for evaluating multiple sites.
Topic(s): Air Quality, Indoor Air, Petroleum Hydrocarbons, Vapor Intrusion
