Speed restricted 20mph zones are being enforced in Oxford as part of a pilot scheme in some areas.
Following consultation with local residents and campaign groups, police are beginning to enforce the lower limit in built-up areas.
Supt Chris Brown, Head of Roads Policing, said: “Our priority has always been and continues to be the safety of the public. We have begun enforcing the 20mph speed restrictions in response to feedback from local communities about specific road safety issues in specific areas.
“This is an opportunity to see the results of proportionate, targeted enforcement in areas where there are concerns around 20mph limits.
“We do hope however that the 20mph speed restriction will continue to be largely self-enforcing by use of signage and road engineering.
“It is anticipated that the majority of infringements will be minor – straying just over the 20mph limit. These will be dealt with by roadside cautions and advice. More serious speeding offences will be prosecuted.”
The campaign group 20's Plenty, which lobbies for a lower speed limit as the default in residential areas, say that lowering urban and residential speed limits to 20 mph has been found to increase a urban journeys by just 40 seconds maximum, on average.
But with that, they say, comes a decrease in child pedestrian accidents by up to 70%.
Portsmouth, Newcastle already sport 20mph zones on most neighbourhood streets, and Leicester, Oxford, Hull, Bristol, Warrington and Islington are some of the places where council officials are using the recent DfT guidelines changes to introduce 20 mph limits on residential streets.
After an unpromising start, having to be bribed by her parents to learn to ride without stabilisers, Sarah became rather keener on cycling in her university years, and was eventually persuaded to upgrade to proper road cycling by the prospect of a shiny red Italian bike, which she promptly destroyed by trapping a pair of knickers in the rear derailleur. Sarah writes about about cycling every weekend on road.cc.