LONDON--(BUSINESS WIRE)--Independent research from Imperial College and Kings College London has demonstrated that closing the shop the door to air pollution on the street during trading hours results in a one-third reduction in the levels of three airborne pollutants hazardous to health - PM2.5 (particulates smaller than 2.5 microns), black carbon particulates and NO2 (Nitrogen Dioxide gas). This is important because: Serious health risks are associated with high levels of air pollution - a pa