The OFD obstacles fall detector is a non-intrusive, standalone system designed to monitor track to detect objects falling from bridges, viaducts and tunnel entrances. Based on µwave radar technology and vital electronics, the OFD uses a horizontal scan directly above track level. When a fallen object is detected in the scanned area, an alarm is transmitted to the train control system or directly to the signal to set it red. The OFD’s architecture is compliant with CENELEC SIL 4, EN 50125-3, EN50126, EN50128, EN50129.