Well i knew it was something to do with safety / testing of different parts but wasn't too sure of the details so here it is from Wikipedia:
TÃVs (German pronunciation: [ËtÊf]; short for German: Technischer Ãberwachungs-Verein, English: Technical Inspection Association) are German organizations that work to validate the safety of products of all kinds to protect humans and the environment against hazards. As independent consultants, they examine plants, motor vehicles, energy installations, amusement rides, devices and products (e.g. consumer goods) which require monitoring. The many subsidiaries of the TÃVs can also act as project developers for energy and traffic concepts, as problem solvers in environmental protection, and as certification bodies. Many of the TÃV organizations also provide certification for various international standards, such as ISO9001:2008 (quality management system) and ISO/TS16949 (automotive quality management system).
The TÃVs as a group became part of the German landscape about 130 years ago, as part of the public and workplace safety initiatives of the time. To increase the safety of their equipment steam engine and boiler owners founded regional "Dampfkessel-Ãberwachungs- und Revisions-Vereine" (DÃV) (steam boiler supervision and revision associations) as self-help organizations to independently supervise their boilers. Their success in preventing accidents was such that in 1871 membership in such an association relieved an owner from government inspections of their boilers.
Because of their success in preventing steam accidents they were trusted with other inspection tasks, too, and the DÃVs became the TÃVs. In 1870 there were 43 TÃVs in total. They were geographically based, as they are today, hence the names, SÃD, NORD, Rheinland, etc. The TÃVs were originally formed to inspect steam boiler installations across the country. A major part of their business is still based on the inspection and certification of boiler and pressure equipment. As the years passed and technology progressed, the 43 TÃVs merged and now there are 4 TÃVs remaining in Germany (TÃV SÃD, TÃV NORD, TÃV Rheinland, and TÃV Saarland / SGS TÃV plus one in Austria (TÃV Austria). The largest is the SÃD group with 19,000 employees and 800 locations worldwide. The only commercial certification body in the world compete the TÃVs combined is Société Générale de Surveillance (SGS), with more than 80,000 employees and headquarter in Switzerland.
