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
Shale gas in the United States natural gas expenditures by as much as 11.6 billion by 2025. America's Natural Gas Association (ANGA) estimates that lower gas prices will add an additional $926 of disposable household income annually between 2012 and 2015, and that the amount could increase to $2,000 by 2035. Over a 100 billion dollars is going to be invested in the US Petrochemical industry and most of it in Texas. Due to emergence of shale gas, coal consumption declined from 2009. One study finds that hyraulic fracturing has contributed to job growth and higher wages. The results of the study "suggest new oil and