This week we interview Andrew Persily, Ph.D. of the National Institute of Standards and Technology. Dr. Persily works on indoor air quality and ventilation in commercial and residential buildings. His work includes the development and application of measurement techniques to evaluate airflow and air quality characteristics in a variety of building types, including large, mechanically ventilated buildings and single-family dwellings. Mr. Persily was also the Steering Committee Chair of the recently published ASHRAE Design Guide "Indoor Air Quality Guide- Best Practices for Design, Construction and Commissioning". This project was a collaboration between ASHRAE, AIA, BOMA, SMACNA, EPA and the USGBC. We are thrilled to have the opportunity to interview Dr. Persily!