TB/T 3498 is the Chinese railway industry standard that defines the lightning test methods applied to railway communication and signalling equipment. Its purpose is to make a laboratory result meaningful for equipment that will be installed along a railway, where the disturbance arrives over cables that run for long distances beside the track and where a single failure can affect the safe movement of trains. The standard therefore specifies the test waveforms and the levels appropriate to the ports of the equipment, distinguishing the power supply ports, the signalling and communication ports and the interfaces to the track circuits and to the interlocking, and it defines the arrangements by which the disturbance is applied and the criteria by which the result is judged. It is the companion to the industry standard that specifies how the protection is designed and installed, and the two are normally cited together in a specification for equipment intended for the Chinese railway network.