More than 60% Reduction in air Pollution levels in Delhi NCR After 11 Days of Lockdown
Dr KK Aggarwal and Dr Anil Kumar ( Heart Care Foundation of India)
During complete Lock down, the values of PM10 and PM2.5 in Delhi-NCR is significantly below the standards. Air quality Index (AQI) is in the good/ satisfactory range.
About a million people are affected worldwide due to COVID 19 pandemic. As a preventive measure, on the appeal of Hon’ble Prime Minister of India, Janta Curfew was imposed on 22-03-2020 and entire India has been lock down for 21 days starting from 25-03-2020.
In Delhi, Lock down is from 23-03-2020 and almost no movement of people and vehicles on roads in last 11 days ( only vehicles related to essential services are moving on roads). This has resulted in improved air quality in Delhi. In Delhi, prominent pollutants are PM10 and PM2.5. As per Central Control Room for Air quality Management – Delhi-NCR, the average values ( 24 hourly) of PM10 and PM2.5 in Delhi- NCR from 21-03-2020 to 02-04-2020 are as follows:
Date : 21-03-2020 ( the day before Janta curfew):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 203.4 | 87.0 |
| 12 Noon | 188.4 | 79.0 |
| 6:00 PM | 187.4 | 79.5 |
| 11: 00 PM | 184.0 | 80.4 |
Date : 22-03-2020 ( the day of Janta curfew):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 182.9 | 86.8 |
| 12 Noon | 177.3 | 88.8 |
| 6:00 PM | 159.6 | 82.7 |
| 11: 00 PM | 129.6 | 72.6 |
Date : 23-03-2020 (starting day of Lock down):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 104.8 | 58.9 |
| 12 Noon | 98.5 | 54.2 |
| 6:00 PM | 96.7 | 51.7 |
| 11: 00 PM | 105.1 | 52.7 |
Date : 24-03-2020 ( Lock down continued):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 115.9 | 58.5 |
| 12 Noon | 118.1 | 58.6 |
| 6:00 PM | 127.7 | 62.1 |
| 11: 00 PM | 109.5 | 55.1 |
Date : 25-03-2020 (Lock down continued):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 94.6 | 45.5 |
| 12 Noon | 81.2 | 39.4 |
| 6:00 PM | 67.8 | 34.7 |
| 11: 00 PM | 72.5 | 37.3 |
Date : 26-03-2020 (Lock down continued):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 75.8 | 40.9 |
| 12 Noon | 75.0 | 39.5 |
| 6:00 PM | 73.2 | 38.4 |
| 11:00PM | 75.3 | 39.1 |
Date : 27-03-2020 (Lock down continued):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 69.6 | 33.8 |
| 12 Noon | 63.3 | 31.0 |
| 6:00 PM | 58.0 | 29.4 |
| 11:00PM | 44.2 | 23.8 |
Date : 28-03-2020 (Lock down continued):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 34.4 | 19,6 |
| 12 Noon | 31.1 | 18.0 |
| 6:00 PM | 31.3 | 17.5 |
| 11:00PM | 36.1 | 20.8 |
Date : 29-03-2020 (Lock down continued):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 42.3 | 22.7 |
| 12 Noon | 47.9 | 23.4 |
| 6:00 PM | 52.9 | 24.2 |
| 11:00PM | 55.0 | 25.2 |
Date : 30-03-2020 (Lock down continued):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 58.7 | 27.2 |
| 12 Noon | 62.2 | 30.4 |
| 6:00 PM | 61.9 | 30.9 |
| 11:00PM | 66.0 | 32.6 |
Date : 31-03-2020 (Lock down continued):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 70.2 | 35.8 |
| 12 Noon | 66.7 | 33.6 |
| 6:00 PM | 68.2 | 35.2 |
| 11:00PM | 66.7 | 33.1 |
Date : 01-04-2020 (Lock down continued):
| Time | PM10 (Standard –100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 61.9 | 27.2 |
| 12 Noon | 67.9 | 29.4 |
| 6:00 PM | 70.0 | 30.0 |
| 11:00PM | 66.8 | 30.7 |
Date : 02-04-2020 (Lock down continued):
| Time | PM10 (Standard – 100 microgram per metre cube ) | PM2.5 (Standard – 60 microgram per metre cube ) |
| 6:00 AM | 67.0 | 32.1 |
| 12 Noon | 62.6 | 28.8 |
| 6:00 PM | 60.0 | 26.9 |
| 11:00PM | 61.6 | 26.8 |
Comparison of PM10 average values ( 24 hourly) before and after lockdown in Delhi- NCR
| Time | PM10 (Standard – 100 microgram per metre cube ) on 21-03-2020 ( the day before Janta curfew): | PM10 (Standard – 100 microgram per metre cube ) on 02-04-2020 ( 11th day of lock down in Delhi): | % reduction in PM10 values after lockdown in Delhi- NCR |
| 6:00 AM | 203.4 | 67.0 | 67.06 |
| 12 Noon | 188.4 | 62.6 | 66.77 |
| 6:00 PM | 187.4 | 60.0 | 67.98 |
| 11:00 PM | 184.0 | 61.6 | 66.52 |
