Some places draw the line between "low" and "moderate" at the level at which pollution starts to cause immediate health effects, reserving the red band for smog that severely affects most people.

在一些地方，以空气污染程度能否对人体健康造成迅疾危害来区分空气质量“低”和“中等”，等到几乎所有人都受到雾霾严重影响的时候才显示红色警告。

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Some places draw the line between "low" and "moderate" at the level at which pollution starts to cause immediate health effects, reserving the red band for smog that severely affects most people.

在一些地方，以空气污染程度能否对人体健康造成迅疾危害来区分空气质量“低”和“中等”，等到几乎所有人都受到雾霾严重影响的时候才显示红色警告。

youdao