Vapor Intrusion

Vapor intrusion (VI) is a process by which chemicals in soil or groundwater migrate to indoor air above a contaminated site. Vapor Intrusion is an emerging concept, the United States Environmental Protection Agency having only issued a draft guidance on the subject in 2002. On March 3, 2008, ASTM International released the "Standard Practice for the Assessment of Vapor Intrusion into Structures on Property Involved in Real Estate Transactions," (ASTM E 2600-08).

In the United States, vapor intrusion is handled in individual states in different ways. One of the most scrupulous guidance documents on vapor intrusion in the nation from the New York Department of Health.