Many thanks to Dr Ben Barratt, of the cutting edge Kings College London Air Quality Team who is advising the campaign and met today. Preliminary research results indicate that closing the door significantly reduces long term health hazards from air pollution in shops on traffic busy streets. It's going to take a long time to resolve the high levels of air pollution (largely from diesel engines) on the streets of our major cities. Short term measures are needed right now and it seems that closing the door is an easy one to help protect shop staff. More soon. (Ben Barratt, image from Kings College London Research Portal)