Commercial Buildings Open Their Windows.

Focuses on the installation of operable windows in high-rise commercial buildings in the U.S. Views of Clark Bisel, senior vice president at Flack and Kurtz in San Francisco, California, on one reason to provide natural ventilation; Challenges that lie in managing the intake of natural pollutants according to David Bearg, an engineering consultant on Indoor Environmental Quality; Factors that can support or thwart the effectiveness of natural ventilation systems; Necessity of operable roofs in greenhouses.