The ammonia gas leak from a cooling plant in the city's northern suburb of Nagerbazaar was controlled on Monday by a disaster relief team of the State government more than 15 hours after it started. Fear and panic still grip the residents of the area which also houses a school and a hospital.
More than 100 people were reported to have taken ill on Sunday evening after inhaling the gas that leaked from a receiver at the cooling plant due to faulty welding of its joints.
Six fire-tenders rushed to the spot to bring the situation under control.
Some of the personnel fell ill as they lacked proper breathing apparatus and there was a delay in locating the source of the leakage.
While the hospital was immediately evacuated, several residents fled the area and the school authorities declared a holiday on Monday.
West Bengal Minister for Fire and Emergency Services Pratim Chatterjee said on Monday that a first information report would be filed against the owner of the plant. The owner and the employees could not be traced.
Chief Secretary Samar Ghosh said the owners of facilities dealing with hazardous chemicals had to conduct periodic inspections to maintain safety standards.
As the area affected by the gas leak was congested, fire services personnel faced difficulties in tackling the situation, he added.
Additional Director-General of Fire Service D.P. Biswas told The Hindu that the receiver containing ammonia gas had developed cracks in welded points due to lack of maintenance. “Most of the gas inside the receiver has already leaked and efforts are on to safely dispose of the miniscule 10 per cent that is left in it,” he said.