Safeguarding the health and wellbeing of future ... . Sarah Jones Wales PH... · Safeguarding the health…

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  • Safeguarding the health and wellbeing of future generations by introducing Wales-wide 20mph speed limits Sarah J Jones, Huw Brunt

    Evidence summary -Effect of 20mph on health and wellbeing

    Adopting 20mph as the default speed limit for Wales can deliver on the goals of the Well-being of Future Generations Act (WFGA). The potential health gain is significant. To assess its effectiveness as a public health intervention, we reviewed the evidence in the context of the act and modelled likely outcomes with

    specific regard to injury prevention and air pollution.

    Estimated effect on road traffic casualties Estimated effect on air pollution related ill health

    A Wales-wide 20mph speed limit has the potential to have significant positive effects on health and deliver on all seven goals of the WFGA. We have estimated some health effects, but it is likely that there will be more, cumulative positives that are greater than individual effects but these are more difficult to measure. The road casualty savings alone make the case for change.

    Road traffic casualties

    Decreases in injuries, crashes, pedestrian and child pedestrian injuries of 17 to 70%

    Air pollution 12% reduction in gear changes, 14% in braking and 12% in fuel use; transport emissions reduced in residential areas by 12%

    32% reduction in NOx when average speeds drop from 31 to 19mph

    48% reduction in NOx emissions with a calmer driving style

    Acceleration accounts for 35-55% of pollutants

    Decrease in NOx emissions of 24-31%

    Active travel 12-25% increase in walking and cycling (Bristol)

    Three fold increase in cycling to schools (Edinburgh)

    Noise 2dB reduction in traffic noise

    Inequalities Narrowed, differences across areas equalised

    Social inclusion Improved and enhanced

    Community cohesion

    Increased, communities improved

    Local business viability

    Improved; people using active travel to visit shops spend more money

    Total (M)

    Annual average in 30mph limits

    Casualties 4818

    Costs 231.9

    Estimated annual average at 20mph

    Casualties 2830

    Costs 137.8

    Savings Casualties 1988

    Saving 94.2

    Deaths YLL Costs (M)

    Nitrogen dioxide

    Current 231 2768 121.70

    20mph 293 3521 154.80

    Change 63 753 33.1 Fine particulate matter

    Current 386 4629 203.50

    20mph 269 3230 142.00

    Change 117 1400 61.5

    Better traffic flow, including public transport and commercial vehicles More walking & cycling due to fewer crashes Local economies more viable & resilient

    And better air quality, enhancing the natural environment & supporting ecological resilience.

    And better cardio-respiratory health due to better air quality Better general health through less obesity & more physical activity due to more active travel & outdoor play Better mental health linked to all of above.

    And reduced inequalities; more deprived areas have greater ranges of traffic speeds & vehicle types.

    And greater social cohesion & connectedness.

    And more walking, cycling & outdoor play.

    And more active travel, less fossil fuel use and fewer impacts of climate change.