In India, vehicle emission standards were implemented in 1991 for gasoline vehicles and in 1992 for diesel vehicles. Since 2000, Euro standards have been followed in India under the name Bharat Stage Emission Standards for four-wheeled vehicles. Since October 2010, Bharat Stage III norms have been implemented throughout India. Bharat Stage IV norms have been in effect in a few cities since April 2010. Bharat Stage IV is expected to be implemented throughout India by April 2017. It is already in use in 13 major cities. Upgrading the emission standards necessitates the upgrading of manufacturing companies' technology, which raises the cost of the vehicle. One of the main reasons for the slow upgrade of emission standards is cost. However, there are some who argue that the cost increase is offset by cost savings in health care because the pollutants that cause disease are reduced as emission standards are raised. Fuels are also important in meeting these emission standards. Fuel specifications have also been aligned with the corresponding European production norms.