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 special purpose bulbs including those used in devices such as household appliances, traffic lights, infrared lamps and automotive lighting. The sale of the most inefficient bulbs was phased out. The first types to go were non-clear (frosted) bulbs, which were taken off the market in September 2009. Also from September 2009 clear bulbs over 100 W were made of more efficient types. This limit was moved down to lower wattages, and the efficiency levels raised by the end of 2012. In practice, some manufacturers and retailers have found a loophole in the new rules so that some incandescents are still