Noble gas as in other metallurgical processes and in the production of silicon for the semiconductor industry. Noble gases are commonly used in lighting because of their lack of chemical reactivity. Argon, mixed with nitrogen, is used as a filler gas for incandescent light bulbs. Krypton is used in high-performance light bulbs, which have higher color temperatures and greater efficiency, because it reduces the rate of evaporation of the filament more than argon; halogen lamps, in particular, use krypton mixed with small amounts of compounds of iodine or bromine. The noble gases glow in distinctive colors when used inside gas-discharge lamps, such
Phase-out of incandescent light bulbs the technology becomes available. Utah has also undertaken a number of LED based lighting projects to regain efficiency. In December 2007, the federal government enacted the Energy Independence and Security Act of 2007, which contains legislation to make incandescent light bulbs more efficient by setting maximum wattage requirements for all general service incandescent light bulbs producing 310–2600 lumens of light. Light bulbs outside of this range are exempt from the restrictions. Also exempt are several classes of specialty lights, including appliance lamps, rough service bulbs, 3-way, colored lamps, stage lighting, plant lights, candelabra lights under 60 watts, outdoor post lights