In 1881 the Zwickau engineer Carl Wolf developed the pit safety lamp. This indicates imminent firedamp explosions. The petrol-powered safety lamp had clear advantages over oil-powered lamps in terms of luminosity and cleanliness. The innovative invention from Zwickau was registered for a patent in 1882, and this was granted for Wolf's lamp in the course of the year. In 1883, Wolf had a few copies of his invention made by hand to test them in coal mines. Production of the lamp commenced with the foundation of Friemann & Wolf (FRIWO) in 1884 as a machine and pit lamp factory. The fuel safety lamp is therefore a genuine Zwickau original. Its efforts have probably saved the lives of a great many miners.
The production of this safe and bright lamp for miners formed the solid basis for the development of the Friemann & Wolf company. FRIWO quickly became a globally active and expanding company with numerous branch offices in Germany and subsidiaries in Belgium, France, England, Austria-Hungary and the USA. Within a short time, FRIWO had become the largest pit lamp manufacturer in the world. However, the success of their petrol safety lamp did not mean that the company's resourceful employees were resting on their laurels. In the years that followed, they also had a decisive influence on the development of electric pit lamps. In 1907, FRIWO built the world's first head lamps with nickel-cadmium batteries, after electric head lamps with lead batteries had been available since 1903.
FRIWO still exists today in the form of two successor companies. Friemann & Wolf Batterietechnik GmbH is a battery manufacturer and FRIWO Gerätebau GmbH is an international manufacturer of chargers, battery packs, power supplies and LED drivers for various industries as well as a provider of E²MS services.
To find out more about all the milestones in Zwickau's history, visitors can visit the Priesterhäuser with the city history collections at