The Brihanmumbai Municipal Corporation on Tuesday invoked Stage 4 restrictions under the Graded Response Action Plan as the city’s air quality deteriorated, halting all construction activity in areas where the air quality index exceeded a value of 200, reported the Hindustan Times.

Municipal commissioner and state-appointed administrator Bhushan Gagrani said that construction work was immediately suspended in Borivali East and Byculla due to poor air quality.

“In areas where the AQI index surpasses the 200-mark, we will be stopping work at all construction sites under the GRAP-4 norms,” he said. “Once the AQI breaches 200, the rule will be implemented immediately without issuing any stop-work notices to the developers. For now, we have immediately implemented the rule and suspended construction work in Borivali East and Byculla which have consistently seen poor AQI.”

The Brihanmumbai Municipal Corporation has clarified that no new trenching permissions will be granted until there is improvement in the air quality. Developers who continue work despite stop-work orders will face penalties under Section 52 of the Maharashtra Regional and Town Planning Act, officials said.

The fourth stage of the Graded Response Action Plan under India’s winter pollution control measures includes a blanket ban on construction activities in areas with severe air quality. Poor weather conditions have led to worsening air quality in Mumbai, prompting the restrictions. Similar curbs were enforced in Delhi earlier this month.

According to the Central Pollution Control Board, an AQI of 0-50 is rated as “good”, 51-100 as “satisfactory” and 101-200 as “moderate”. Readings between 201 and 300 fall into the “poor” category, while 301-400 is considered “very poor”. AQI levels above 400 are classified as “severe”.

Authorities have urged residents to take precautions and avoid activities that contribute to pollution during this period.