Inert gas asphyxiation lacks oxygen and consists of an asphyxiant gas (one or more of argon, nitrogen or carbon dioxide), causing the animals to lose consciousness. Argon and nitrogen are important components of a gassing process which seem to cause no pain, and for this reason many consider some types of controlled atmosphere killing more humane than other methods of killing. However, "stunning" is often done using carbon dioxide. If carbon dioxide is used, controlled atmosphere killing is not the same as inert gas asphyxia, because carbon dioxide at high concentrations (above 5%) is not biologically inert, but rather is toxic and also
Incandescent light bulb even when properly white-balanced, the color reproduction will not be perfect. For a given quantity of light, an incandescent light bulb produces more heat (and thus consumes more power) than a fluorescent lamp. In buildings where air conditioning is used, incandescent lamps' heat output increases load on the air conditioning system. While heat from lights will reduce the need for running a building's heating system, in general a heating system can provide the same amount of heat at a lower cost than incandescent lights. Halogen incandescent lamps have higher efficacy, which will allow a halogen light to use less power