The air quality in Delhi on Wednesday fell into the “very poor” category after remaining “poor” for two days, reported PTI. The overall Air Quality Index of the city was recorded at 338 in the evening, according to data from the System of Air Quality and Weather Forecasting and Research.

An AQI between 0 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”.

Anand Vihar recorded an AQI of 431, Bawana 426, Rohini 416 and Mathura Road 403 – all in the “severe” categories.

A fire that has been burning at the Bhalswa landfill site in North Delhi since October 20, has added to the pollution. An unidentified official of the Delhi Fire Service said firefighting operations were continuing at the garbage dump.

“Due to continuous discharge of methane gas from the landfill, fire erupts randomly,” said the official. “Two fire tenders are currently working on containing the fire at the site.”

The city’s air quality had shown signs of improvement on Monday as it moved to the “poor” category from “very poor”. However, unidentified officials said that the pollution could worsen in the coming days due to toxic smoke emanating from the fire at the landfill.

North Delhi Mayor Adesh Gupta and New Delhi Municipal Council Commissioner Madhup Vyas visited the landfill site on Tuesday following which the civic body announced several remedial measures.