UC Berkeley

The present study provides detailed investigation of source characteristics and emission dynamics of volatile organic compounds (VOCs) in a single-family house in California, utilizing time- and space-resolved VOC measurements for eight weeks in summer and five in winter. In total, about 300 VOCs were measured. Spatially resolved VOC measurements, in conjunction with airflow investigation using multi-tracer technique, reveal that VOCs in the living space were mainly emitted directly into the living space, with minor contributions from coupled interior spaces (crawlspace and attic) and from outdoors. Time series of most indoor VOCs were characterized by elevated baseline levels with episodic enhancements. The high baseline level highlights the importance of continuous emissions into the house from building materials and contents. Associated emissions rates were quantified with 2-h resolution. Influences of environmental parameters on emissions were explored. Episodic enhancements were associated with occupants and their activities, such as cooking and personal-care-product use.