Correction fluid the Montreal Protocol on Substances That Deplete the Ozone Layer, and then the slightly safer trichloroethylene. Thinners currently used with correction fluid include bromopropane. Because it contains organic solvents (volatile organic compounds), unused correction fluid thickens over time as volatile solvents escape into the air. It can become too thick to use, and sometimes completely solidifies. Therefore, some manufacturers also sell bottles of solvent as "thinner", a few drops of which will return the correction fluid to its original liquid state. To avoid the inconveniences of organic solvents (safety and availability), some brands of fluid are water-based. However, those have
Tourism in Antarctica tourists that come to visit Antarctica. The Environmental Protocol to the Antarctic Treaty does not specifically address tourism, but its provisions go some way to minimising the adverse impacts of tourists because, once ratified, the protocol is legally binding over all visitors to the Antarctic, whether on government or private trips. In 1994 the Treaty countries made further recommendations on tourism and non-government activities. This "Guidance for Visitors to the Antarctic" is intended to help visitors become aware of their responsibilities under the treaty and protocol. The document concerns the protection of Antarctic wildlife and protected areas, the respecting of