Most of the 43 labourers who died in the fire that broke out early on Sunday morning in a factory in a congested central Delhi neighbourhood died of asphyxiation, emergency services personnel have said. A National Disaster Response Force (NDRF) team, dispatched to aid the Delhi fire department with rescue operations, swept the structure with gas detectors and found large amounts of toxic smoke and hazardous carbon monoxide. The NDRF team also found that some windows at the rear of the building were sealed shut, thereby trapping poisonous gases inside the already cramped and dimly-lit interiors.
"We found carbon monoxide (CO). After this we searched the area manually. The entire third and fourth floors of the building were engulfed with smoke. CO levels were very high," Aditya Pratap Singh, NDRF Deputy Commander, was quoted by news agency PTI.
Carbon monoxide is an odourless and colourless gas that, when inhaled, is harmful to human beings because it displaces oxygen. Inhalation leads to loss of consciousness, suffocation and death.
"There was a room... where most of the workers were sleeping... which had only a single space for ventilation. The maximum number of workers rescued was from the third floor. Due to the burning of materials present in the building CO was formed," the NDRF Deputy Commander added.
According to Atul Garg, Director of Delhi Fire Service, the building that burned down also did not have the necessary clearances and fire safety equipment.
The massive fire, in the Anaj Mandi area of the national capital, was reported at 5.22 am. Thirty-five fire trucks were rushed to the area but narrow lanes and crowded buildings made it difficult for emergency personnel to reach the blaze in time.
Experts say factories and small manufacturing units that are set up, often illegally, in old and overcrowded quarters of big cities and towns; the cost of land is relatively cheaper.
Such units often also serve as sleeping quarters for labourers who often migrate from villages and small towns in hope of jobs in the big city and try to save money by sleeping overnight at their workplaces.
Like several others in the neighbourhood the building that burned down housed illegal factories and workshops. Mohammad Masih, who owns the adjacent building, told NDTV that the brothers who owned the building had rented it out for workshops - bags, printing paper and plastic were manufactured there and hundreds of labourers lived in the building.
A first information report (FIR) has been registered against the two brothers, one of whom - Rehan - has been arrested by Delhi Police and the other has been taken in custody.
Sunday's fire is the worse Delhi has seen since the Uphaar Cinema tragedy in 1997 which killed 59 people. In January last year a similar incident - a fire broke out in an illegal fireworks factory in northwest Delhi - killed 17 people and injured two others.
Delhi Chief Minister Arvind Kejriwal, who visited the site of the fire on Sunday afternoon, has announced an inquiry into the accident; the report is to be submitted within a week. Mr Kejriwal also announced compensation of Rs 10 lakh to the families of those who died and Rs 1 lakh to each of those injured.
Prime Minister Narendra Modi also tweeted condolences, as did President Ram Nath Kovind, Home Minister Amit Shah and Congress leaders Rahul Gandhi and Sonia Gandhi. The Prime Minister, who called the fire a "horrific", announced compensation from the Prime Minister's National Relief Fund.
With input from PTI
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