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
Sulfur hexafluoride with satisfactory accuracy at very low concentrations, and the Earth's atmosphere has a negligible concentration of . Sulfur hexafluoride was used as a non-toxic test gas in an experiment at St. John's Wood tube station in London, United Kingdom on 25 March 2007. The gas was released throughout the station, and monitored as it drifted around. The purpose of the experiment, which had been announced earlier in March by the Secretary of State for Transport Douglas Alexander, was to investigate how toxic gas might spread throughout London Underground stations and buildings during a terrorist attack. Sulfur hexafluoride is also routinely