New Delhi: In a measure to reduce further deterioration in air quality of Delhi, the state government on Thursday announced a halt on their movement from 11pm of 8 November to 11 pm of 11 November.

A notification issued by the transport department ordered the traffic police and the Municipal Corporations of the Delhi to prohibit the entry of heavy and medium goods vehicles, except those carrying essential commodities, in Delhi.

The move comes as Delhi’s air quality index (AQI) post-Diwali dropped to 642 in the “severe plus emergency". This is nearly double the pollution levels of last year post Diwali, when the AQI was around 367. In 2016, the AQI was 425.

According to the System of Air Quality and Weather Forecasting and Research (SAFAR) data, an AQI of “severe plus emergency" means that even healthy people may suffer respiratory illness on prolonged exposure.

SAFAR’s data showed that PM 2.5 level was more than eight times the permissible limit, while PM 10 was six times the permissible limit.

The deterioration in air quality is being witnessed despite the Supreme Court directing that only green firecrackers be lit and that too for two hours between 8 pm and 10 pm on Diwali. Despite the ban, firecrackers were burnt in huge numbers, leading to a thick blanket of smoke, which drastically reduced visibility.