Air pollution alerts to be displayed across London
Air quality alerts will be introduced across the capital during the worst incidents of air pollution, The Mayor of London has announced.
Notices will be displayed at bus stops, river pier stops, Tube stations and on road signs, from 15 August.
Sadiq Khan said he hoped the warnings would "become less and less frequent" as pollution is reduced.
The Supreme Court ruled in April that London's air quality breaches European clean air rules.
A Clear Air consultation launched by Mr Khan in July revealed 79% of people wanted to be told when pollution was high.
The warnings will be displayed the day before and during high pollution days at 2,500 bus countdown and river pier signs, the entrances to all 270 Tube stations and on 140 roadside dot matrix signs.
Mr Khan said it was the first step towards London putting in place a comprehensive air pollution incident plan.
"I believe that Londoners have a right to know about the quality of the air that they breathe," he said.
London air pollution
Premature deaths a year in London linked to air pollution
500,000 aged under 19 who live in areas that breach EU limits
443 schools that have unsafe pollution levels
86 of these are secondary
2025 year London is expected to meet EU limits
The mayor has proposed a series of measures to tackle the problem, including introducing charges for the most polluting vehicles in the Congestion Charge Zone.
Professor Paul Monks, chairman of the Air Quality Expert Group, said the signs would help people understand the scale of the air pollution problem.
"Information is a good thing. The next big step is to make sure policies benefit both air quality and climate change," he added.
Leon Daniels, from Transport for London, said the alerts were an important part of the group's work to improve air quality.
A more detailed consultation will take place later this year and some measures could be implemented as early as 2017.