The air quality in the Delhi-NCR (National Capital Region) area continues to get worse as today’s air quality index was reported as being 407 microgrammes per cubic meter, when the national limit for poor air quality is 60 microgrammes, and the international limit is 25 microgrammes for PM2.5. This toxic figure was a combination of the readings from 35 regions across Delhi and 47 regions in the NCR were the ranges were 368 and 507 microgrammes per cubic meters and 359 and 498 microgrammes per cubic meters, respectively.
PM2.5 is the unit of measurement of there being particles of suspended pollution in the air with a diameter of 2.5 microns or less. PM10 is another aspect that is recorded by the Central Pollution Control Board (CPCB), where particles of 10 microns or less are recorded. The PM2.5 reading is of more concern because these smaller particles have the tendency to lodge far further in a person’s lungs when inhaled. The international permissible amount of PM2.5 and PM10 are 25 and 50 microgrammes per cubic meter of air, but India’s standards are 60 and 80 microgrammes per cubic meter of air. In spite of this larger leeway in the standard, the levels of pollution in the air in Delhi and the NCR are several times higher than thought to be safe, prompting readings of “emergency” levels of air pollution in some regions where it was measured.
According to a CPCB official, “It was smog in the morning, the air quality has dropped overnight as the wind speed and direction have changed from the earlier easterly to north-westerly from Punjab and Haryana.”