The boy hopped in the snowed-in family car to warm up, but the engine was running and the exhaust pipe was blocked by snow, causing carbon monoxide to accumulate in the car.

CNN: STORY HIGHLIGHTS

The department warned about the dangers of carbon monoxide poisoning from trying to stay warm in a car with exhaust pipes blocked by snow.

CNN: STORY HIGHLIGHTS

These include the exhaust gases such as nitrogen oxides (NOx), non-methane volatile organic compounds (NMVOCs), and carbon monoxide (CO).

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