A system is provided for deterring unauthorised access to an area such as a railway crossing 10. The system comprises a directional alarm output device 12,14,16,18,20 such as a directional horn or speaker e.g. a Long Range Acoustic Device (LRAD), a directional light generator, or a directional air current generator. The directional alarm output device may be steerable and orientated by a human or alternatively the system may include a sensor 32 for detecting the presence of a person and for generating a directional alarm output based thereon. The sensor 32 may be an infrared image sensor. The system may warn level crossing users of an approaching train, may be used as a trespassing deterrent, or may be used for deterring workers from leaving an authorised working area.
Trespassing deterrence
2023-03-01
Patent
Electronic Resource
English
Crossing and trespassing accidents worry safety men
Engineering Index Backfile | 1940