MADRID, Dec. 5 (Xinhua) -- The Madrid Town Hall activated its anti-pollution protocol for the first time in almost 11 months due to high levels of nitrogen dioxide (NO2) measured in the city's air on Wednesday.
The protocol, previously used on Jan. 24, was put into effect after levels of 180 micrograms of NO2 per cubic meter were measured at three separate points in the city for two continuous hours and with a weather forecast predicting dry and calm weather conditions for the coming days.
The first level of the protocol sees traffic on the main access roads into the city and the M-30 ring road limited to a maximum speed of 70 km an hour. Meanwhile, the City Hall recommends residents and visitors use public transport whenever possible.
Should contamination levels continue, the City Hall will consider further measures, which involve banning non-residents from parking inside the M-30 and prohibiting the use of private vehicles on alternate days based on their license plate numbers.
The anti-pollution protocol has been activated just five days after the City Hall put its new "Madrid Central" traffic scheme into operation.
"Madrid Central" saw the establishment of a low-emissions zone covering 472 hectares in the city center, banning all petrol vehicles registered before 2000 and diesel vehicles registered before 2006, unless they belong to residents.
The scheme aims to reduce N02 levels by 23 percent by 2020 and promote green transportation.