California Environmental Quality Act Office of Planning and Research to develop and recommend new guidelines to analyze greenhouse gas impacts under CEQA. California’s Natural Resources Agency adopted new guidelines on December 31, 2009, requiring lead agencies to analyze greenhouse gas emissions under section 15064.4 during their CEQA review through California. The major category of greenhouse gas emissions resulting from human activities is carbon dioxide. Several other primary gases also include methane, nitrous oxide, sulfur hexafluoride, perfluorocarbons, and hydrofluorocarbons. Greenhouse gas sources resulting from project construction activities are typically generated from transportation of materials to the project site and petrol based equipment used during construction
Sulfur hexafluoride circuit breaker Sulfur hexafluoride circuit breaker Sulfur hexafluoride circuit breakers protect electrical power stations and distribution systems by interrupting electric currents, when tripped by a protective relay. Instead of oil, air, or a vacuum, a sulfur hexafluoride circuit breaker uses sulfur hexafluoride (SF) gas to cool and quench the arc on opening a circuit. Advantages over other media include lower operating noise and no emission of hot gases, and relatively low maintenance. Developed in the 1950s and onward, SF circuit breakers are widely used in electrical grids at transmission voltages up to 800 kV, as generator circuit breakers, and in distribution systems