30 km/hour speed limits save lives

The sixth UN Global Road Safety Week addresses the risk of deaths from road traffic accidents, which is fundamental to achieving the Sustainable Development Goals (SDGs), specifically those affecting health security, sustainable cities, poverty, and reducing inequalities among and within countries.

A traffic sign promotes 30km/hour streets for everyone who uses them, especially the most vulnerable, like pedestrians, cyclists, children, older people, and people with disabilities.

This year, Global Road Safety Week takes place from May 13-17.
Policies that tackle the of impact road traffic, and create environments for safe, sustainable and inclusive transport options, also unlock action for protecting the climate and gender equality.
A paradigm shift in how streets are designed, starting with low speeds where people and traffic mix, makes streets safe, accessible, enjoyable and equitable for all road users, delivering multiple benefits for all whilst accelerating action across interlinking SDGs.
Streets with 30 km/hour (20 mph) speed limits save lives and protect all who use them, especially the most vulnerable, like pedestrians, cyclists, children, older people, and people with disabilities.
This speed limits on streets where people and traffic mix help prevent road traffic deaths and promote physical activity because when streets are safe, people walk and cycle more.
Evidence from around the world shows that low speed streets reduce the risk of serious injuries and save lives.
A road safety scheme introduced in Tanzania has been shown to cut road injuries by as much as 26 percent and has now expanded to 50 high-risk school areas in nine countries.
In Toronto, Canada, road crashes fell by 28 percent since speed limits were reduced from 40 to 30 km/h in 2015, which led to a reduction in serious and fatal injuries by two thirds. In Colombia, Bogota has included 30km/h zones in a package of measures in its Speed Management Plan that have reduced traffic fatalities by 32 percent. 
A study from London found that lower speed limits (in this case 20mph zones) were associated with a 42 percent reduction in road casualties, while in Bristol the introduction of 20mph limits was associated with a 63 percent reduction in fatal injuries between 2008 and 2016.
Other studies suggest that there can be a casualty reduction of up to 6 percent for each 1 mph speed reduction for urban roads. The World Health Organisation has concluded that an increase in an average speed of 1 km/hour results in a 3 percent higher risk of a crash and a 4 to 5 percent increase in fatalities.
Above 30 km/hour impact speeds, pedestrians are at considerably greater risk of death. This is even greater for the young and elderly.  In the distance a 30km/hour car can stop, a 50km/hour car is still driving. Higher speeds narrow motorists’ peripheral vision and impact their reaction times.
Over many years, surveys from around the world have consistently shown that the majority of people agree that 30 km/hour is the correct speed limit for residential roads. Indeed, low speed streets help reduce congestion and are widely popular.
A recent global YouGov poll in 11 countries for the Child Health Initiative found that 74 percent of people supported restrictions on streets around schools if it allowed children to walk or cycle to school more safely, including limits on speed.
In UK surveys, 70 percent of motorists say that they agree that 20 mph (30 km/h) is the right limit for streets where people live.
Surveys in Scotland suggest 65 percent are in favour, and one in four people think that it would make them more likely to walk or cycle in their everyday life.
Evidence also suggests rapid acceptance across Europe.
There are also significant health benefits from slowing traffic, including supporting a shift to active lifestyles through walking and cycling. The social interactions that people have with others on the street are important for building community and collective wellbeing. Slower traffic also reduces road danger, improves noise and social cohesion.
In urban situations, the peak speed between congestion points or junctions rarely impacts on journey times. Real-world tests have shown across most typical urban journeys, the time difference between driving at a maximum of 30 km/hour or 50km/hour is minimal.
Congestion and time spent waiting at traffic signals are often more significant on journey times than the speeds that vehicles travelling between them.
Areas designed for slow moving vehicles can also potentially eliminate the need for some traffic signals, creating a more equal relationship between road users who yield for each other.
Low speed streets can actually make life better for motorists. Safer roads will help shift some shorter urban trips away from private vehicles, reducing congestion and the associated emissions. Air pollution affects all road users, but professional drivers are disproportionately exposed to it, increasing their health risks.
In low speed streets, vehicles tend to move more smoothly, with fewer accelerations (which is linked to exhaust emissions in internal combustion engine vehicles) and decelerations (which can cause tyre wear and associated particulate matter), leading to lower pollution. Speed bumps may lead to small, local increases in pollution due to increased acceleration and braking, but the impact of these is low.
Fewer vehicles mean a reduction in air pollution and CO2 emissions (even from electric vehicles), as well as wider health benefits from increased physical activity.

By Times Reporters
(Latest Update May 27, 2022)