Madrid pollution alert: these are the key points

Madrid has been in a state of alert for several days, caused by the warning issued by the city council, which has led to the activation of the pollution protocols for nitrogen dioxide. This substance is produced by car exhaust fumes and builds up in cities, where traffic is heavy.

This substance is produced by the combustion of certain materials, such as tobacco, wood or engine combustion. It is very dangerous, and inhaling it can cause u a long list of health problems. If a high concentration of nitrogen dioxide is breathed in a short time, lung cells rapidly deteriorate. If the concentration is low but is breathed in for a long time, emphysema can develop.

The main symptoms experienced by a person exposed to nitrogen dioxide are odema of the eyes, throat and nose irritation, along with difficulty breathing, tiredness and even nausea. When the amount in the atmosphere exceeds 200 micrograms per cubic metre of air for more than 18 hours, the alarms go off. This is what has happened in Madrid.

The measuring stations record the level of nitrogen dioxide in the atmosphere

In the capital, as in almost all large cities, there are several measuring stations that record NO2 levels. When these levels reach those thresholds, the alert protocols begin to be activated. If two stations in an area record that level of pollution for two hours, a pre-warning is issued. When 250 micrograms per cubic metre is reached, a warning is activated, which becomes an alert when it reaches 400 micrograms per cubic metre for three consecutive hours.

Depending on severity, a first warning is issued internally, which puts municipal authorities on alert. In a second step, a warning is issued to residents through public services such as the municipal website and public transport information panels. In a third phase, the municipal and Autonomous Community health protocols are activated, to address the problems that will inevitably arise from this pollution.

The protocol consists of four phases, each more restrictive than the previous one. It begins with Phase 1, which in Madrid’s case requires reducing speed in the central area, bounded by the M-30, to 70 km/h. Madrid has activated Phase 2, which, in addition to the ban on driving above 70 km/h on the M-30, adds a ban on parking in regulated parking zones, the blue and green zones.

In these zones only taxis, vehicles for people with reduced mobility, transport vehicles and zero-emission vehicles may park. Be careful, because hybrid vehicles are not considered zero-emission and can be fined.

In the third phase traffic is reduced to 50%. To achieve this, the number plates of cars are checked. On one day vehicles with even-numbered plates may circulate and on the next day odd-numbered ones. Public transport and commercial vehicles are still excluded, as are motorcycles and mopeds and vehicles that may circulate in Phase 2.

Finally, Phase 4 is the most restrictive, as it includes the M-30. Four scenarios are also contemplated, ranging from Scenario 0, in which information work is carried out for one day, to the Alert Scenario, which activates Phase 4 and in which public transport promotion work is carried out. Madrid has reached Scenario 2, which means activating Phase 2 for three days.

So Madrid residents only have to be patient and wait for the preventive measures to reduce the build-up of NO2 to less dangerous levels so that they can breathe more safely. In any case, the use of public transport in large cities may be a good solution to avoid this serious problem.