Table 1. Breakpoint of different pollutants for AQI calculation, by CPCB (2014).

AQI category (Range)	PM10 24-h	PM2.5 24-h	NO2 24-h	SO2 24-h	NH3 24-h	O3 8-h	CO 8-h
Good (0–50)	0–50	0–30	0–40	0–40	0–200	0–50	0–1.0
Satisfactory (51–100)	51–100	31–60	41–80	41–80	201–400	51–100	1.1–2.0
Moderate (101–200)	101–250	61–90	81–180	81–380	401–800	101–168	2.1–10
Poor (201–300)	251–350	91–120	181–280	381–800	801–1200	169–208	10.1–17
Very poor (301–400)	351–430	121–250	281–400	801–1600	1,200–1,800	209–748	17.1–34
Severe (401–500)	430+	250+	400+	1,600+	1,800+	748+	34+