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 instantly at any temperature, their extremely long lifetime is unaffected by cycling on and off, they have no glass to break, and they don't emit UV rays that fade colored materials. LED lamps radiate almost no heat, and can be either multi-directional or unidirectional, eliminating the need for a mirrored reflector in the bulb or fixture. LED lamps can emit saturated colored light. Disadvantages include spectrum limitations due to discrete emission colors, and higher up-front cost than incandescent bulbs. Botswana has an exchange program distributing CFL bulbs. Of the members of ECOWAS, Cape Verde, Guinea, Mali, Nigeria, Benin and Togo