title: Long-term evaluation of the controlled pressure method for assessment of the vapor intrusion pathway.
abstract: Vapor intrusion (VI) investigations often require sampling of indoor air for evaluating occupant risks, but can be confounded by temporal variability and the presence of indoor sources. Controlled pressure methods (CPM) have been proposed as an alternative, but temporal variability of CPM results and whether they are indicative of impacts under natural conditions have not been rigorously investigated. This study is the first involving a long-term CPM test at a house having a multiyear high temporal resolution indoor air data set under natural conditions. Key observations include (a) CPM results exhibited low temporal variability, (b) false-negative results were not obtained, (c) the indoor air concentrations were similar to the maximum concentrations under natural conditions, and (d) results exceeded long-term average concentrations and emission rates under natural conditions by 1-2 orders of magnitude. Thus, the CPM results were a reliable indicator of VI occurrence and worst-case exposure regardless of day or time of year of the CPM test.
authors.affiliation: School of Sustainable Engineering and the Built Environment, Ira A. Fulton Schools of Engineering, Arizona State University , Tempe, Arizona 85287, United States.
authors.forename: Chase
authors.initials: C
authors.lastname: Holton
authors.forename: Yuanming
authors.initials: Y
authors.lastname: Guo
authors.forename: Hong
authors.initials: H
authors.lastname: Luo
authors.forename: Paul
authors.initials: P
authors.lastname: Dahlen
authors.forename: Kyle
authors.initials: K
authors.lastname: Gorder
authors.forename: Erik
authors.initials: E
authors.lastname: Dettenmaier
authors.forename: Paul C
authors.initials: PC
authors.lastname: Johnson
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D016902:Air Pollution, Indoor / Q000032:analysis*; D000399:Air Pressure; D004784:Environmental Monitoring / Q000379:methods*; D006798:Housing; D006801:Humans; D018570:Risk Assessment; D013997:Time Factors; D055549:Volatile Organic Compounds / Q000032:analysis*; D014835:Volatilization
chemical_list: D000393:Air Pollutants; D055549:Volatile Organic Compounds