Sulphur Emission Control Area traces of heavy metals, refined petroleum products containing halogen compounds, sewage sludge and sludge oil. The Marine Environment Protection Committee (MEPC) has strongly encouraged members to use the scheme to report the greenhouse gasses emissions. Those gasses include Carbon dioxide, Methane, Nitrous oxide, Hydrofluorocarbons, Perfluocarbons, and Sulfur hexafluoride. The purpose of making the guidelines on CO2 emissions is to develop a system that would be used by ships during a trial period. In 2013 new regulations described in a chapter added to the MARPOL Annex VI came into effect in order to improve "energy efficiency of international shipping. The regulations
Nitrous oxide Thomas Clover invented the "gas-ether inhaler" in 1876, however, it became a common practice at hospitals to initiate all anaesthetic treatments with a mild flow of nitrous oxide, and then gradually increase the anaesthesia with the stronger ether or chloroform. Clover's gas-ether inhaler was designed to supply the patient with nitrous oxide and ether at the same time, with the exact mixture being controlled by the operator of the device. It remained in use by many hospitals until the 1930s. Although hospitals today are using a more advanced anaesthetic machine, these machines still use the same principle launched with Clover's