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
Phase-out of incandescent light bulbs lives than incandescent bulbs. When bulbs are used infrequently, such as in little-used closets and attics, it may take a long time to compensate for the higher initial cost of the bulb. The overall energy savings from changing to more efficient lighting depends on the climate. In warm climates, efficient lighting has the additional energy-saving effect of reducing the amount of cooling required. In cold climates increased heating energy demand may offset some of the lighting energy saved with efficient lighting. A report published in January 2008 found that in Los Angeles, where incandescent lighting results in increased air conditioning,