Air pollution has spiked above normal levels for up to ten consecutive days in Milan, Rome, Florence, Turin, Venice and several parts of Emilia-Romagna. 

With the air not forecast to clear for several more days, several cities have introduced restrictions on driving, central heating and open flames, including a ban on diesel vehicles in central Rome that is expected to affect some 700,000 drivers.

Diesel vehicles are banned within Rome's 'Fascia Verde' green zone on Tuesday. Image: Comune di Roma

The alarm concerns levels of fine particle pollution known as PM10, which can be linked to respiratory disorders, allergies, poisoning and cancer.

Warm, windless weather has helped trap pollution and created what's been dubbed a 'smog emergency' across large parts of Italy, with dozens of towns reporting poorer than average air quality over the past fortnight.

The measures in place across Italy on Tuesday include:

• Rome: ban on all diesel vehicles in the 'Fascia Verde' limited traffic zone between 7:30-10:30 am and 4:30-8:30 pm, with all-day restrictions on higher-polluting vehicles in emissions categories Euro 0-3.
• Milan: heaviest polluting diesel vehicles (Euro 1-4) are banned and drivers are required to switch off their engines while stopped. Bonfires, barbecues and fireworks are also banned.
• Turin: ban on diesel vehicles up to and including older Euro 5 models for most of the day.
• Emilia-Romagna (Piacenza, Parma, Reggio Emilia, Modena, Ferrara, Ravenna): Euro 1-4 diesel vehicles are banned from 8:30 am to 6:30 pm. Heating is limited to 19 degrees C in homes and 17 degrees in shops.
• Venice: all-day ban on two-stroke Euro 0 motorbikes, Euro 0-1 petrol cars and Euro 0-4 diesel cars, as well as Euro 1-3 diesel goods vehicles.
• Florence: restrictions for most of the day on two-stroke motorbikes, Euro 1 petrol vehicles, Euro 2-3 diesel vehicles, and Euro 1-2 goods vehicles.

Italy's permitted limit for PM10 pollution is 50 micrograms per cubic metre, above which air quality is considered dangerously poor.

Air pollution is typically worst in northern Italy, where densely populated cities, industry and farming create emissions and mountains trap it in low-lying plains. Industrial Brescia, Monza, Milan, Turin, Venice and other cities in the Po Valley regularly exceed safe limits.

But Rome too, where sea winds help clear the exhaust fumes spewed out by relentless traffic, has seen its air quality plummet this month. At least four of Rome's 15 monitoring stations measured pollution above the limit on Sunday, the most recent check published, in some cases for the tenth time in 12 days.

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