The rail operator says the cigarettes, which release a vapour instead of harmful smoke, could unsettle other passengers. In response, manufacturers said the devices are not lit, and the vapour is harmless. An FCC spokesman said: We have a no-smoking policy, regardless of the type of device customers would like to smoke. Our concern is that e-cigarettes will unsettle other passengers or cause people to think that smoking real cigarettes is allowed. He added: Many airlines also enforce this for similar reasons. A statement from manufacturer Electric Zebra said: There is no risk to others from passive smoking, as the e-cigarette produces water vapour, not smoke. The vapour does not leave any bad odours and evaporates in seconds. FCC added that a bylaw, dealing with unacceptable behaviour, allowed it to ban the devices. The legislation states: No person shall molest or wilfully interfere with the comfort or convenience of any person on the railway.