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 to 40 percent more efficient than standard incandescent lamps designed for a 2000-hour life. Depending on size, voltage, and designed life, small low-voltage halogen lamps can have 70% higher efficacy than large line-voltage lamps. The high operating temperature of halogen bulbs may be a safety hazard in some applications. A compact fluorescent lamp (CFL) uses a fluorescent lamp tube which is curved or folded to fit into the space of an incandescent bulb and contains a compact electronic ballast in the base of the lamp. Compared to general-service incandescent lamps giving the same amount of visible light, CFLs use one-fifth