Indore: PM2.5 refers to particles that have diameter less than 2.5 micro-meters and remain suspended for longer. It is recorded that the PM2.5 levels in air quality of the city in commercial areas rose to 162.5 µg/m3 dropping the measure to a very poor level in the COVID-19 year on Diwali day. The readings released by the pollution body reflect the effectiveness of the appeals made by the government and administration on observing a safe Diwali. As per data released by the local pollution control board (PCB) about 144 percent rise in PM2.5 level was registered in the air quality of the city in comparison to last year. In 2019 the SPCB had recorded PM 2.5 levels at 66.6 µg/m3 on Diwali day 2019. The sharp rise in PM2.5 levels in the air took the air quality of the city in commercial areas to very poor category when considered on the individual parameter. The condition of PM2.5 level in mixed areas was not much of a difference as they too recorded a level of 133.3 µg/m3 falling in the same category. Particulate Matter (PM) is a mixture of solid and liquid particles that are suspended in the air. These are categorized into coarse, fine and ultrafine. Recordings of PM10 particles were also not a relief as also recorded a sharp rise from last year’s readings but remained in the moderately polluted range. This year the PCB recorded PM10 levels on Diwali day at 226.2 µg/m3 in commercial areas of the city. A rise of 51 percent on average from the last year's reading of 149 µg/m3 of the same. So2 and No2 levels also rose from last year’s rating on Diwali day. So2 level was recorded at 18.5 µg/m3 and No2 was recorded at 24.4. Last year they stood at 16.4 µg/m3 and 19.7 µg/m3 in the commercial areas. However, sound levels were not of much change as the average equivalent sound level in dB stood at 85.39 from 85 dB of last year. Delhi's air situation Severe, it reels under air pollution Delhi govt received an invitation to participate in climate dialogue on curbing emissions MET department predicts heavy rainfall in Karnataka