空气质量

空气质量指数AQI 空气污染指数API

空气质量指数 AQI(Air Quality Index), 也叫空气污染指数API(Air Pollution Index)。

空气质量周报的主要内容为：空气污染指数、空气质量级别和首要污染物。空气污染指数就是将监测的几种空气污染物的浓度值简化成为单一的数值形式，并分级表示空气污染程度和空气质量状况。污染指数的分级标准是：1、污染指数在50以下对应的空气质量级别为一级，即优；2、污染指数在50以上、100以下对应的空气质量级别为2级，即良；3、污染指数在100以上、200以下对应的空气质量级别为3级，即轻度污染；4、污染指数在200以上、300以下对应的空气质量级别为4级，即中度污染；5、污染指数在300以上对应的空气质量级别为5级，即重度污染。

根据我国空气污染的特点，目前计入空气污染指数的项目暂定为：二氧化硫、氮氧化物和总悬浮颗粒物。二氧化硫主要来自燃煤废气，它是生成酸雨的元凶；氮氧化物主要来自于汽车尾气；总悬浮颗粒物主要来自燃煤排放的烟尘和地面扬起的灰尘。取这3种污染指数最大的作为首要污染物，并将首要污染物的污染指数确定为该城市的空气污染指数。

AQI Numbers

An index with numbers can be a quick way to tell people how good or bad something is. For example, you might say your school lunch is a 1 (very good) or a 5 (yucky). The Air Quality Index uses numbers from 0 to 500. These numbers are used to decide the AQI color. On days measuring less than 100, the air is clean. If the air is dirtier, the numbers get bigger. On days measuring more than 100, the air can be bad for you to breathe.

What is the AQI?

The EPA and your State environmental agency measure pollution in the air. Then they use the Air Quality Index, or AQI, to tell the people about the air. An index can be a quick way to tell people how good or bad something is. The AQI uses colors, and numbers, and words

to tell you about the air.

Here is how the AQI numbers match up with the AQI colors:

AQI Numbers 0 to 50 51 to 100

Colors Green Yellow