For five days in February, 11 of Switzerland’s 26 cantons imposed 80 km/h speed limits on all motorways and major roads in an attempt to reduce high levels of fine particles.

The police reported that motorists observed the limits, and overall traffic levels on motorways went down by 14%. Traffic was said to have “flowed more homogenously” and no jams were reported. Particulate emissions were between 5% and 10% down in motorway areas, but the levels subsequently returned to “normal” after the experiment ended.

Together with an extension of a lower speeds experiment in the Netherlands, this adds to the evidence that speed restrictions may become more widespread to combat high pollution levels.

T&E’s Swiss member VCS/ATE is campaigning strongly on particle filters and is keen to stress that speed limits alone will not bring enough of a reduction in emissions.

This news story is taken from the May 2006 edition of T&E Bulletin.