Measurement and Control of Ventilation Rates in Commercial Buildings in Caifornia

Ventilation of buildings with outdoor air is necessary to maintain acceptable indoor air quality and health conditions. California’s Title 24 Standards specify minimum ventilation rates for buildings. The purpose of this project was to advance the science and technology needed to better control minimum outdoor air ventilation rates in existing and new commercial buildings in California. The project team performed several related research tasks including: a modeling evaluation of the effects on energy and indoor air quality of various means of demand-controlled ventilation for controlling minimum ventilation rates in California commercial buildings; a field assessment of the performance of two commercially available technologies for measuring rates of outdoor air intake into air handlers; and sets of experiments that evaluated the performance of carbon dioxide sensors and people counters for use as part of building ventilation rate control systems. Results of this research were used to develop occupancy-specific guidelines for using carbon dioxide sensors in demand-controlled systems, measuring ventilation rates, and developing guidance on selection and use of technologies for measuring outside air intake rates.