The Swiss Federal Railways has been highlighting the environmental impact of noise pollution in a bid to convince passengers and companies to use railways rather than highways.
The move follows a three-year study, which shows that the ecological gap between road and rail travel is diminishing in other respects.
The study was conducted jointly with the Federal Institute of Technology in Zurich.
"In terms of emissions into the air like nitrogen oxide, road traffic will catch up ecologically because the laws have been tightened," said Thomas Baumgartner, a researcher in the department of environmental sciences.
"And, of course, the Swiss railways already use hydro-electricity so there's not much potential for reducing the ecological impact of electricity production as there would be in neighbouring countries where oil or coal is more widely used."
The new study showed that 40 per cent of environmental impact is caused by noise. The authors of the report said that if the Federal Railways followed a noise-reduction strategy, the ecological advantage of rail would be maintained.
"The potential to reduce noise emissions is much larger by railways than by truck or road transport in general," said Baumgartner.
"You can build anti-noise walls along specific stretches of railway but you can't plaster our roads with anti-noise walls because this would be much too expensive."
Travelling by train is hugely popular in Switzerland. About 20 per cent of all passengers and some 36 per cent of all goods go by rail. The combined figure of 25 per cent is double the European average.
Baumgartner believes that economy and ecology can co-exist if people care about the environment.
"If society thinks the environment is not worth protecting, then the economic argument will always win out," he said.
"But if the demand for a good and safe environment is there, then the ecological trade-off is quite different and that is what we have seen in the case of noise with the railways. It is now worthwhile to invest in anti-noise measures but before when noise wasn't a problem, the economy dominated."
by Vincent Landon
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