Article from 01.02.2016 | Last changed: 07.08.2023
… and a daily average of 50 μg/m 3 have been set for particulate matter smaller than 10 micrometres (PM 10 ). The daily average may not be exceeded on more than 35 days per calendar year. … are allowed access, air quality in inner cities becomes significantly better: 10 to 12% less particulate matter, equivalent to 20 fewer exceedence days. The …