The AQI in several places in Haryana and neighbouring Punjab was recorded in the 'poor' category on Saturday.

According to the Sameer app that provides hourly updates of the national Air Quality Index (AQI) published by the Central Pollution Control Board, the AQI in Chandigarh -- the joint capital of the two states -- was also in the 'poor' category.

While the AQI improved slightly in a few places in Haryana, including Gurugram, Jind, Ambala and Kurukshetra, it remained in the 'poor' category. The AQI in these places was 'very poor' on Friday, the morning after Diwali.

At 9 am on Saturday, the AQI was recorded at 212 in Gurugram, 285 in Jind, 224 in Ambala and 262 in Kurukshetra against readings of 344, 340, 308 and 304, respectively, 24 hours ago.

Among other places in Haryana, the AQI was recorded at 218 in Bahadurgarh, 224 in Bhiwani, 229 in Charkhi Dadri, 224 in Fatehabad, 204 in Hisar, 277 in Karnal, 251 in Sirsa and 243 in Yamunanagar.

Sonipat's AQI was in the 'very poor' category with a reading of 324.

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', 401 and 450 'severe' and above 450 'severe plus'.

Chandigarh's AQI was recorded at 289 against 303 on Friday.

In Punjab, Amritsar's AQI continued to remain 'very poor', deteriorating to 346 from a reading of 314 at 9 am on Friday.

The AQI in Mandi Gobindgarh, however, improved to 206 from 331 recorded 24 hours ago.

Jalandhar recorded an AQI of 239, Khanna 206, Ludhiana 291 and Patiala 231.

Punjab had on Friday witnessed the season's biggest spike in farm fires with 587 total cases being reported across the state.

Except for the headline, this story has not been edited by The Telegraph Online staff and has been published from a syndicated feed.