Mercury uses in Explosives, Electrical and Measuring Appliances

Hg fulminate [Hg(ONC)₂], which was discovered by Howard in 1799, became widely used in percussion and blasting caps in the 19th century, since it was the initial detonator in the caps invented by Nobel in the 1860's. They were used for dynamite and other explosives with widespread use in mining and construction of canals, roads, and railways and in ammunition. (reference)

Just before World War I, the USA consumed 250-300 tons, more than one third of actual Hg consumption in the USA, in their production of fulminate. Since dry fulminate is extremely sensitive to thrusts, it had to be produced at the assembly sites of percussion and blasting caps.) Sweden imported most caps assembled, but produced the fulminate needed for additional caps at a couple of factories for explosives, which are estimated to have consumed 0.7 tons Hg per year around 1940 corresponding to about 2% of imported Hg. This has not been accounted for in earlier inventories on Hg use in Sweden, and although it makes up a minor quantity in Sweden, warrants an assessment of the quantities of Hg consumed for fulminate production in Germany and UK, where the production of percussion and blasting caps for both national demand and a substantial export was large at the time. After World War II, fulminate was replaced by lead azide and nitrogen tetrasulphide.

Before the ban in 1992, Sweden imported clinical thermometers containing large quantities of Hg, while smaller quantities of Hg were used in domestic production of other thermometers, measuring instruments and rectifiers. In Sweden, Hg use for measuring instruments and electrical products was large between World Wars I and II, while corresponding use in the USA dominated for a longer period and still is large as a result of aversion of several producers to replace Hg-containing thermometers, thermostats for housing, and switches in cars with Hg free ones. However, this use is changing also in the USA, where several states have recently introduced bans on the manufacture, sale and distribution of Hg fever thermometers and Hg-added novelty items. Comparatively small amounts of Hg are still used for fluorescent tubes in both Sweden and the USA, although the emissions to the environment from used tubes are significant if they are not recycled without breakage of the tubes.

The consumption of Hg for production of Hg-oxide batteries and of alkaline batteries, to which HgCl₂ was added to improve performance and shelf life, increased drastically in the 1980's in the US, Japan, and some West European countries. In Japan, 65% of the Hg consumed in 1990 was used for battery production. In contrast, Sweden had no domestic production of Hg-oxide batteries, and only limited amounts of Hg were consumed for production of manganese dioxide batteries, while considerable quantities of batteries containing Hg were imported. In order to reduce Hg emissions from waste incineration and diffuse emissions, the authorities in most industrialized countries enforced legislation in the 1990's, banning both production and import of Hg-containing batteries with a few exceptions, such as certain batteries for hearing aids and button-cells containing less than two percent Hg by weight, which are permitted in the EU until 2004.