Introducing a city-wide 30 km/h speed limit in Amsterdam has had positive effects not only on road safety but also on accessibility to jobs by car.

This is the conclusion of a new peer-reviewed study published in the Journal of Transport Geography by researchers from the University of Twente, they Dutch Institute for Road Safety Research (SWOV) and the Municipality of Amsterdam. The publication sheds light on how lower speed limits can improve both safety and fairness in access to opportunities.

Consequence

The study focused on the spatial consequences of the speed limit policy, with particular attention to equity between different neighbourhoods. To capture these effects, the researchers developed a new model that integrates travel time and crash risk into a single measure of accessibility. This approach allowed them to evaluate how reduced driving speeds influence people’s ability to reach jobs across the city, while also factoring in the likelihood and cost of crashes.

The findings reveal that when both travel time and safety are considered, the 30 km/h measure improves overall car accessibility. Areas with higher crash risks, which often coincide with lower-income neighbourhoods, benefit significantly. By reducing the likelihood of severe crashes, the policy enhances access to employment opportunities more equitably across Amsterdam. The study also shows that both low- and high-income residents gain from the measure, suggesting that the intervention supports a fairer distribution of opportunities city-wide.

Outweighing

Although lower speed limits do result in slightly longer travel times, these are outweighed by the improvements in safety. By monetizing both crash risk and travel time and integrating them into a single framework, the researchers demonstrated that the benefits of safety gains more than compensate for the modest delays. This approach prevents overestimation of accessibility levels and highlights areas where speed reduction policies can have the greatest positive impact.

The study concludes that integrating safety into accessibility assessments provides a more realistic and comprehensive understanding of how speed reduction measures affect urban mobility. The methodology, which combines Safety Performance Functions, crash cost estimation, and job accessibility modelling, can also be applied to other cities considering similar interventions.

Conclusions

For transport policy, the Amsterdam case provides strong evidence that reducing speed limits can simultaneously advance safety, accessibility and equity goals. The research shows that speed reduction is not simply a trade-off between safety and travel time but can, when properly assessed, lead to broader benefits for residents across social and economic groups.