ATHENS — Air quality in many areas of Athens will be extremely poor on Wednesday due to high concentrations of fine particulate matter (PM) – tiny particles with a diameter of less than 2.5 microns that can penetrate the respiratory system and affect the heart and lungs – released by the major fire in Varybobi.

According to the National Observatory of Athens (NOA), Attica residents in the areas where PM 2.5 readings are very high should avoid going outdoors and keep also doors and windows tightly shut. If they have to go out, they should wear a high-protection mask (N95, KN95 or FFP2) that provides protection from fine particulate matter.

Levels of PM2.5 can be monitored in real time at the following website, where data from the European air quality measurement platform PurpleAir: Real-Time Air Quality Monitoring is uploaded, based on new-generation sensors of the Internet of Things: https://www.purpleair.com/map?opt=1/mPM25/a10/cC0#10.21/38.021/23.7292

The units given are in microns per cubic metre and need to be divided by a factor of approximately 1.8.