Buildings consume 40% of the country's energy. That's why Purdue conducts vital research in heating, ventilation, air-conditioning, refrigeration, and compressors. Not only does HVAC research affect energy and the environment, but human-building interactions can show how people function more efficiently, more happily, and more safely in high-performance buildings. Since 1958, Herrick Labs has been the leading testbed in this field, and is now the largest academic HVAC lab in the world. In addition to labs for compressors and refrigeration, they also host Living Labs, which allow human-building interaction studies with precise controls of temperature, humidity, light levels, airflow, and acoustic treatments. Every two years, Herrick Labs hosts one of the largest international conferences in Compressor Engineering, Refrigeration and Air Conditioning, and High Performance Buildings.