Littering is a huge environmental and societal problem. In some contexts, like train stations, this is evidenced very clearly. Although there is a smoking ban in all Belgian train stations since 2023, there has been an increase in cigarette butt littering around the entries of train stations. Therefore, the NMBS decided to partner with Sapience to strive for cleaner train stations.
At Sapience, we use a variety of research methods to delve into real behavior and go beyond claimed (or reported) behavior. In this case, we adopted nudging, an innovative behavioral technique. Nudging is based on the knowledge that human behavior is often irrational, but in a predictive way. Specifically, we designed the nudges around the following principles:
- Make it easier to dispose the cigarette butts (through a disposal pit that was built into the ground)
- Attract attention by using attractive colors that highlight the disposal pit
- Increase awareness by showing images of a hand holding a cigarette to highlight the correct action
The nudges were found to be very effective:
✅ -44% decrease in cigarette butt littering in the busy Brussels South station
✅ -50% reduction within 3m from the pit by making the pit more salient
✅ -50% decrease beyond 6m from the pit, through ground signage guiding smokers to the pit
Based on these results, NMBS decided to implement the nudges to the 100 busiest train stations in Belgium. Davide Rigoni, Managing Director of Sapience, also received the opportunity to present this case at the Stop Litter Now summit in Brussels, organized by the Clean Europe Network.
We’re proud to support the NMBS and to reduce littering through behavioral science.
Nudging in action
Interested to see our nudging approach in action? Watch the 2min video below, including interviews with Davide Rigoni (Sapience) and Wouter Derijck (NMBS).