大たい気き質しつ指し標ひょう

noun

air quality index; AQI

Technical term used in environmental science and public health contexts.

• 今日きょうの大たい気き質しつ指し標ひょうは非ひ常じょうに悪わるいので、外がい出しゅつを控ひかえたほうがいい。

  Today's air quality index is very poor, so it's better to avoid going outside.