Understanding Indoor VOC Emissions: Insights from NIST’s CASA Study

A recent study from the National Institute of Standards and Technology (NIST) has shed light on the complex behavior of volatile organic compounds (VOCs) in residential environments (1). This research is crucial for understanding indoor air quality and its implications for health and the environment.

Using a surface flux chamber, the researchers measured VOCs emitted from various surfaces in the house. They compared these results with air quality measurements taken from the entire home and outside. Interestingly, they found that the emission rates varied significantly—up to 10,000 times—across different VOCs. When comparing total emissions, they discovered a strong correlation between the flux chamber measurements and ambient air tests, suggesting that VOCs migrate over time from their original sources, such as building materials, to other surfaces within the home.

This study reveals a vital insight: as a house ages, VOCs can distribute themselves throughout the indoor environment. Some compounds, like aromatics and monoterpenes, have decreased since the house was built, while others, particularly aldehydes, have remained consistent.

The Role of Environmental Consultants

Environmental consultants can help homeowners and builders assess and mitigate indoor air quality issues through various strategies:

1. Conduct Thorough Assessments: Consultants can conduct thorough evaluations of indoor air quality, measuring VOC levels and identifying potential sources.
2. Remediation Strategies: By recommending low-VOC materials and improved ventilation systems, consultants can help reduce harmful emissions from indoor surfaces.
3. Ongoing Monitoring: Implementing regular air quality monitoring programs ensures that VOC levels remain within safe limits over time.
4. Education and Awareness: Consultants can educate homeowners about the sources and effects of VOCs, empowering them to make informed decisions about building materials and maintenance.