In fact, even Ren Xiaosu did not know that keeping the heater on for an extended period of time in an idling vehicle would cause carbon monoxide poisoning. If the occupants of the vehicle were awake, it might be fine. But if they were not, then it might really be possible they would not regain consciousness ever again.
When Li Ran heard what Zhou Yingxue said, she immediately woke the others up. Everyone started shivering in the cold wind after they got out of their vehicles. Some of them were even showing symptoms of carbon monoxide poisoning already.
Carbon monoxide poisoning would cause a person to feel very uncomfortable. Everyone sat in the wilderness wrapped tightly in their clothes, but when a gust of cold wind blew past, the coldness seeped right into their bones.
Curious, Ren Xiaosu asked Zhou Yingxue, "How'd you know something like that?"