Similar data has been found in the United States (graphic here), but the new BMJ study provides even more empirical proof of the concept even after adjustment for other factors. From the new study:
Results: The introduction of 20 mph zones was associated with a 41.9% (95% confidence interval 36.0% to 47.8%) reduction in road casualties, after adjustment for underlying time trends. The percentage reduction was greatest in younger children and greater for the category of killed or seriously injured casualties than for minor injuries. There was no evidence of casualty migration to areas adjacent to 20 mph zones, where casualties also fellslightly by an average of 8.0% (4.4% to 11.5%).
Conclusions: 20 mph zones are effective measures for reducing road injuries and deaths.
Results: The introduction of 20 mph zones was associated with a 41.9% (95% confidence interval 36.0% to 47.8%) reduction in road casualties, after adjustment for underlying time trends. The percentage reduction was greatest in younger children and greater for the category of killed or seriously injured casualties than for minor injuries. There was no evidence of casualty migration to areas adjacent to 20 mph zones, where casualties also fellslightly by an average of 8.0% (4.4% to 11.5%).
Conclusions: 20 mph zones are effective measures for reducing road injuries and deaths.
The New Haven Safe Streets Petition has called for the introduction of 15-20 MPH speed zones around schools, hospitals and dense pedestrian zones, as well as along quiet residential streets where children play on the street. When will the city begin implementing them?
