Delhi Told To Stay Indoors Amid Deteriorating Air Quality

Air quality in Delhi, which remained 'very poor' for the fourth straight day on November 27, is set to deteriorate further, leading to the Delhi government advising people to stay indoors as much as possible. High moisture content and lack of winds had triggered the spike, the city government said.

Meanwhile, the Centre said it would take "harsh measures", if needed, to prevent any repeat of the recent smog episode.

The Central Pollution Control Board registered the air quality index (AQI) at 362 on November 27, 10 units more than yesterday, on a scale of 500. The AQI takes into account levels of suspended particulate matter and gases like nitrogen dioxide.

An AQI between 301 and 400 is classified as 'very poor' which can trigger respiratory illness on prolonged exposure. The 24-hour average concentration (rolling) of PM2.5 and PM10 were 291 and 171 microgrammes per cubic metre (ug/m3), respectively, at 8 pm, multiple times above the prescribed standards 60 and 100, according to the readings of SAFAR (System of Air Quality and Weather Forecasting And Research).

During the day, levels of these ultrafine particulates were even higher. CPCB monitors, essentially 17 of its stations located across the city, recorded the highest levels of PM2.5 and PM10 at 224 and 353 ug/m3.

Emergency measures will kick in if PM2.5 and PM10 concentration cross 300 and 500 ug/m3 and stay there for 48 hours at a stretch.

According to SAFAR, an agency under the Ministry of Earth Sciences, PM2.5 and PM10 levels will rise further over the next three days.

CPCB's air lab chief Dipankar Saha said winter was not taking root in the city due to fluctuating wind directions, the northwest and the west. Saha said wind direction from the north would soon stabilise and surface winds would gain momentum, leading to dispersion of pollutants.

However, pollution would not turn 'severe plus', like it had on November 8 and persisted for nearly a week, Saha said.

The city government issued a health advisory, urging people to avoid smoking and stepping out during the early morning and late evening hours. It also appealed the city residents to carpool and use public transport, and not to burn dry leaves, crop residue, wood, coal, etc. The government asked schools to avoid outdoor assemblies, sports and other physical activities in the early morning hours.

Union Environment Secretary CK Mishra said: "As government, we are determined to not let this (smog episode) happen again, which may mean taking harsh measures, and there will be (such measures). Because, we care for lives and we cannot ignore that aspect," he said.

With inputs from Housing News