109 million people face another day of poor air quality as smoke from blazes in Ontario drifts over the US Sign up for the Breaking News US newsletter email Tens of millions of Ame…

109 million people face another day of poor air quality as smoke from blazes in Ontario drifts over the US Tens of millions of Americans face another day of smoky skies, irritated eyes and bad air quality, as Canadian wildfire smoke spread again over huge swathes of the US, affecting about 109 million people across the midwest, mid-Atlantic and north-east. The pungent wildfire blanketed cities such as Chicago and Detroit, where residents on Friday were warned to stay indoors and reduce activity levels after the air quality index reached a “hazardous” 361, according to the government website AirNow. The smoke drifted into Baltimore and Washington DC overnight, creating very unhealthy air quality with index values of 281 and 247, respectively, as of 6am eastern time. In New York City, where smoke has blanketed the city since Tuesday, air quality stands at an “unhealthy” 184. Philadelphia and Cleveland had readings considered “very unhealthy” at about 260. Other parts of Michigan, Minnesota and Wisconsin also recorded readings in the “hazardous” range. Overall, the global air quality index showed pollution in five major North American cities at higher levels than Kinshasa or Nairobi in Africa – the next cities on the list. Nasa’s Fire Information for Resource Management System, or Firms, shows pockets of Canadian wildfires reaching deep into the Northwest Territories. In Michigan, the state’s department of environment, Great Lakes and energy recommended closing windows, minimizing the opening of doors and using HVAC systems rated Merv-13 or higher. “If you must be outdoors for short periods of time, an N95 or P100 respirator marked with NIOSH is recommended,” that alert said.