Millions of acres of wildfires in Canada have spread unhealthy air across the United States. Pictures of the orange sky in New York City are spreading around the world. For example, a widely shared video shows how the end of the George Washington Bridge dissolves into smog.

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Even the Canadian wildfires give off so much smoke that a region of more than 100 million people has a bad air warning. The US Environmental Protection Agency, the US Environmental Protection Agency, says people should pay close attention to air quality values. Especially if they have health problems.

Hundreds of forest fires are raging in the Canadian province of Quebec in particular. The situation caused by smog is especially dangerous for people with asthma, chronic obstructive pulmonary disease, or heart problems. Pregnant women should also be careful, as well as the elderly and children.

The Environmental Protection Agency (EPA) has a warning system based on the Air Quality Index. There is also a system with color codes associated with it. Code Orange applies to part of the United States, including Chicago and Atlanta. This means a danger to people with fragile health. According to the Environmental Protection Agency, it’s possible that this was caused in part by local conditions there.

In New York City, the largest city in the country, the second highest or highest warning level applies: purple or maroon. The air there is exceptionally unhealthy for everyone. If necessary, people should stay home, authorities advise.

Due to poor visibility due to the smoke, fewer planes were allowed to take off in New York State. So at least 120 flights have been cancelled, according to reports CNN. Some schools have decided to keep their students indoors. And on Broadway, a show was canceled after ten minutes. The 30-year-old actress, Jodie Comer, had such breathing problems that she could not continue playing. Baseball games have also been cancelled.