Delhi's air quality deteriorates to 'severe' level ahead of Diwali

Air pollution surges to nearly 15 times World Health Organisation safety limits for particulate matter

Smog shrouds New Delhi. While politicians blame farmers burning stubble for the pollution, experts says vehicle emissions are the cause. AP

Air pollution in the Indian capital New Delhi reached “unhealthy” levels on Monday, according to government figures, as the city braces for more toxic air during the coming festive season.

Pollution levels in Delhi spike around Diwali, the festival of lights, that also marks the beginning of winter season in the northern plains bringing down temperatures and winds.

Delhi’s AQI turned “poor” and “severe” with the Anand Vihar station recorded 420 AQI early morning on Monday, according to the Central Pollution Control Board, the country’s top environmental watchdog.

An AQI between zero and 50 is considered “good”, 51 and 100 “satisfactory”, 101 and 200 “moderate”, 201 and 300 “poor”, 301 and 400 “very poor” and 401 and 500 “severe”.

The PM 2.5 concentration in the city was 74 microns per cubic metre — nearly 15 times the safety limits of particulate matter (PM) 2.5 of the World Health Organisation, as per the IQAir — a Swiss air quality technology company that analyses global air quality data.

Fine PM 2.5 particles penetrate deep into lungs and into the bloodstream and are blamed for chronic respiratory and cardiac diseases.

The WHO in its revised guideline considers five micrograms per cubic metre as the safe level of exposure of particulate pollution.

Air monitoring website World Air Quality Index, a non-profit initiative that promotes air pollution awareness, put the toxicity levels in the capital city at hazardous levels with an AQI of 749 early in the morning.

New Delhi, home to 20 million residents, suffers from air pollution throughout the year but toxic air levels surge during winter, when winds push the smoke from farmlands into the city and shroud it under a blanket of smog.

It was ranked as the world's most polluted capital cities earlier this year.

Authorities at the weekend asked the agencies to implement measures under the Graded Response Action Plan — a set of anti-air pollution measures to be followed in the capital.

Under the plan, the unregistered construction and demolition activities at sites have been advised to stop, while mechanised sweeping of roads and water sprinkling will be done.

Heavy fines will also be imposed for violation of the curbs on open burning of biomass and municipal solid waste.

Delhi’s chief minister Arvind Kejriwal had last month announced these measures to tackle air pollution.

Mr Kejriwal and Prime Minister Narendra Modi’s government blame stubble burning in neighbouring Punjab state for the pollution.

Despite a ban on stubble burning more than 51,000 cases have been reported in Punjab in the past 10 days.

Experts have said emissions from vehicles are the biggest contributor to particulate pollution in the capital.

Vehicle emissions contributed up to 53 per cent to the city’s pollution between October and November last year, according to figures.