Passive Samplers for Sewer Gas

Accurately Assessing a Common Vapor Intrusion Pathway

Sewer lines and other utilities can act as preferential pathways for volatile organic compounds (VOCs) and allow toxins to migrate into buildings and contribute to or be the primary pathway for vapor intrusion. Beacon Environmental helps consultants investigate this pathway by providing advanced passive samplers designed to collect time-integrated air samples directly from sewer and other utility lines.

The resulting samples are analyzed by Beacon Environmental’s accredited laboratory to target a broad range of VOCs as part of a complete vapor intrusion risk assessment.

Benefits of Beacon Passive Samplers

• Time-weighted average concentrations reported for improved decision making
• Collect sample over hours, days, or weeks
• Easy to use – No pumps or regulators required
• Simple procedures for sampling in manholes or sewer cleanouts
• Hydrophobic adsorbents used that are ideal for high-humidity environments
• Target chlorinated and petroleum compounds
• Analysis by accredited EPA Method TO-17 (TD-GC/MS)
• Sensitive – Detection limits in the ppt range
• Accurate and defensible

Backed by Research

For more than a decade, Beacon Environmental has supported consultants, regulators, and academia with understanding the importance of this VI pathway.  

Research from work completed with Dr. Kelly Pennell from the University of Kentucky can be found at:

Exposure Pathway Analysis Using Passive Diffusion Air Sampling Methods to Sample Sewer Air in Manholes and Cleanouts
26th Annual International Conference, San Diego, California, 2016

Considerations for Evaluating Alternative Pathways as Part of Vapor Intrusion Assessments
28th Annual International Conference, San Diego, California, 2018: Vapor Intrusion: Cal/EPA Focus on Protecting Current and Future Building Occupants

Occurrence of Chlorinated Volatile Organic Compounds (VOCs) in a Sanitary Sewer System: Implications for Assessing Vapor Intrusion Alternative Pathways
Roghani, et al Sci Total Environ. 2018 Mar; 616-617:1149-1162. doi: 10.1016 / j.scitotenv.2017.10.205. Epub 2017 Nov 14

As research has demonstrated their importance, sanitary sewer lines and other utilities are now standard pathways evaluated during VI assessments by regulators, such as described in the January 2026 Wisconsin DNR VI Guidance Document (RR800).