Detectors of the Line 4.0 series are designed for industrial applications within a large variety of environmental conditions, which imposes specific requirements to such equipment. The environmental hazards include operation in zones with potentially explosive atmospheres and in surroundings with extreme temperatures, frequent variations of humidity, presence of vapours, aggressive or corrosive gases. Diffusion detectors of Line 4.0 enable customized configuration options for every single component of the device, including selection of enclosures, to adjust its design to field conditions of each specific facility.