Indoor Air Quality
- Develop Sampling Programs and Protocols
- Soil Gas Sampling
- Indoor Air Sampling
- Presampling Assessments/Property Owner Interviews
- Vapor Intrusion Studies
- Indoor Air Quality Assessments
- Human Health Exposure Assessments
- Remedial Actions to Mitigate Indoor Air Impacts
Indoor air quality has become an increasingly important environmental issue for residences and commercial spaces in recent years. Improvements in energy efficiency have led to more tightly sealed buildings with reduced ventilation rates. This can lead to a build-up in levels of air pollutants in poorly ventilated spaces. In addition, many people are spending a greater percentage of their time indoors (approximately 90%). As a result, exposures to potentially harmful levels of indoor air pollutants are a significant concern.
D&B has performed air sampling services in association with the investigation of a wide variety of sites including active and closed landfills, active and abandoned manufacturing facilities, former manufactured gas plant (MGP) sites and petroleum storage facilities. The air monitoring and sampling programs conducted by D&B have ranged from collection of a single sample from a single on-site building to collection of numerous samples from multiple structures up to 1 mile from a project site. The characterization of outdoor (ambient air) and indoor air quality is an essential element in the investigation of contaminated sites due to the fact that contaminants often migrate through subsurface soil and groundwater migration pathways to off-site locations. Site contaminants can then enter buildings and other living spaces where direct exposure to the contaminants can occur.
D&B conducts indoor air sampling in accordance with applicable federal and state criteria. Sampling has been conducted using a wide variety of devices, including passive sampling devices (PSDs), summa canisters for collection of volatile organic compounds (VOCs), and dust meters for measurement of respirable dust.
As a first step, the firm typically utilizes a Photoionization Detector (PID) in conjunction with a Flame Ionization Detector (FID) to determine the relative concentrations of VOCs in soil gas in parts per million (ppm) concentration ranges around buildings and structures. A PID/FID unit is also used to scan typical soil gas entry points into a foundation, such as cracks, annulus spaces around utility lines, and sumps. Based on the completed soil gas survey and interviews with the property owner, indoor air sample locations will be selected.
After the collection and validation of the data has been completed, a qualitative risk/exposure assessment will be prepared to determine if the identified Contaminants of Concern (COCs) pose an unacceptable risk to human health based on current and anticipated use of the building/structure, potential receptors and potential contaminant migration pathways.
Remedial actions are undertaken if the exposure assessment identifies an unacceptable risk with regard to indoor air contaminants. The remedial actions may range from increasing the ventilation of a building to the complete removal of a contaminant source located upgradient of the affected building.
The firm has designed and implemented several programs to mitigate exposures of building occupants to contaminants in indoor air on a time-critical and long-term basis. Interim Remedial Measures (IRMs) have involved the installation, operation and maintenance of small-scale air filtration units in on-site buildings, and nearby off-site residential or commercial structures into which the migration of VOCs has occurred or is a potential concern.
For more information on D&B’s Environmental Remediation Services, please contact Senior Vice President, Richard W. Walka, at (516) 364-9890 x 3006.