Wildfire smoke entered Manchester homes despite closed windowsWildfire smoke can infiltrate homes even when windows are kept closed, while opening them to escape extreme heat may significantly increase indoor pollution, preliminary research by University of Manchester scientists suggests. Researchers analysed real-time air-quality data from 23 homes across Greater Manchester between 1st and 26th July, during two periods of wildfire activity in the nearby Pennine hills. On 17th July, when outdoor smoke levels peaked, every monitored home exceeded the World Health Organization’s 24-hour guideline for PM2.5. However, this cooling measure also appeared to increase the amount of wildfire pollution entering homes. The effects of wildfire smoke were detected indoors in all 23 monitored properties, including homes up to 60km from the fires on the moors outside Manchester.