Despite the petrol lamp's improved safety measures, such as the integrated igniter and magnetic lock, the mesh caps could still be damaged in the rough underground world of mining.
Even a second mesh basket, which became common from 1910 onwards, could not provide a full proof protection against explosions. This became apparent when the tragic mining disaster took place in the Hendrik State Mine in Brunssum in 1928.
The type of petrol lamp used at that time was the same as the Friemann & Wolf lamp you can see here. A lamp also commonly used in the State Mines at that time was made by the manufacturer Wilhelm Seippel.