Evaluation of the lowering of speed limit and installation of Actibump in Linköping, Sweden
Effects on speeds and yielding behaviour
Trivector Traffic has performed an independent evaluation on the implementation of an Actibump and a lowering of the speed limit from 50 km/h to 40 km/h.

The results, in short:
  • 85th-percentile went from 47,2 km/h to 37,0 km/h.
  • Average speed decreased by 11 km/h from just over 41 km/h to just under 31 km/h.
  • Aside from the Actibump implementation the speed limit was changed from 50 km/h to 40 km/h. Lowering the speed limit (including a change of signage) is a means of speed reduction in and of itself.
  • As a general rule of thumb a decrease of the speed limit of 10 km/h gives a decreased speed of 2,5 km/h, in reality.
  • Yielding behaviour was already good before installation and still increased by ten percentage points from 72 % to 82 %.