number and installation location of signaling devices in the area to be reached by the signal. Depending on the product and the application, the choice of signaling color (a clear or a red cover) can have [...] accordance with VDE 0833-2 - changes relating to visual signaling devices in fire alarm systems The provisions of the standard for visual signaling devices in fire alarm systems, DIN EN 54-23, are legally [...] installers and designers of fire alarm systems. Siemens loop signaling device and Pfannenberg Xenon flashing light PYRA ® The standard for visual signaling devices, EN 54-23, came into force in the Member States