Just goes to show even with all the windows &amp; doors shut and the MVHR ventilation system switched off, with high levels of PM2.5 #AirPollution outside some will still find their way inside your home. 

8μg/m3 in my living room &amp; 71.5 μg/m3 outside #Chorley 

#Health
#AirPollution #Chorley #Health