Equipment for measuring temperatures and pressure, e.g. manometers, barometers, sphygmomanometers, thermometers. The use of mercury for this was banned in the EU in 2007, effective as of 2009. Equipment produced before this, e.g. antiques, are allowed 
Mercury has been used in button batteries to prevent the buildup of internal gases that can cause the battery to bulge and leak . The mercury can be both elemental, e.g. , and salts, e.g. .