The most vulnerable sample of Delhi for the deadly winter pollution

Rana, 42, is an auto rickshaw driver. The three-way taxi, with their distinctive green and yellow look, is a common sight in the streets of Delhi, where they offer a cheap and ready-made vehicle on the streets with heavy city congestion.

The job gives Rana a steady income to help support his family, but he comes at risk – especially during the winter – when the already toxic air of the city becomes even more lethal.

"I have difficulty breathing." When I return home, I have chest pain, I cough, "said Rana, who was a rickshaw driver for 24 years.

Naresh Kumar Rana spends up to ten hours a day, exposed to the devastating air of Delhi during the winter months.

Worst in the world

Pollution in India is believed to be responsible for one million deaths per year. In Delhi, where air ranks among the worst in the world, the dangers are particularly acute for those whose work requires them to be outdoors.

"What is our life worth?" We are prone to breathing problems because we drive for 14 to 15 hours every day of the week, "said Rahul Jaiswal, who has been working as a rickshaw auto driver for over 20 years.

The sides of motorized rickshaws are open to the elements, making drivers vulnerable to the effects of smog.

"We have heard in the news that the breath of this air is like smoking 20 cigarettes, so imagine what it is like for us," Jaiswal added.

According to Jaiswal, there has been a clear deterioration in air quality in the city in recent years. "This has been going on for five years, especially during the winter, the difference is enormous."

Breathing in Delhi air is equivalent to smoking 44 cigarettes a day

Rotha Singh, a Delhi traffic officer, has also seen air quality deteriorate. However, the impact on his health was not so damaging because he was given a special mask of infection.

"The mask provides relief, I have no health problems, I have no real breathing problems as I wear the mask in the mornings and evenings when the infection is worse," said Singh.

Rana also tried to use a pollution mask, but found that she offered him some relief. An effective mask like Singh's can cost about $ 20, a price too high for Rana, whose home pay is equivalent to about $ 4 a day.

Instead, Rana connects a wet scarf around her face when it leads to winter pollution.

Delhi Rohtas Singh's traffic officer wears a specially designed pollution mask.

Air quality in Delhi is worsening

Air quality measurements provided by the Delhi Pollution Control Commission monitor the pollutant levels across the city in real time.

Last week he saw air quality in the fall of the city, with the Central Pollution Control Council recording an average air quality level 203 on Tuesday.

These levels are based on the concentration of fine particles, known as PM2,5, per cubic meter. Microscopic particles less than 2.5 micrometers in diameter are considered particularly harmful because they are small enough to occupy deep in the lungs and pass into other organs causing serious health risks.

The World Health Organization believes that a PM2.5 density below 25 micrograms is safe, almost one-tenth of the levels currently seen in Delhi.

These levels peak around the time of Diwali, the Hindu fire festival celebrated with fireworks, which falls on Wednesday of this year.

Last month, the country's Supreme Court banned the sale of most detonators amid worries that their use during annual celebrations will again send contamination levels.

A congestion during a day of fresh air in Gurgaon, New Delhi.

Systemic problems

The polluting fireworks are not the only reason behind the toxic cloud. In fact, in addition to periods of intense use like Diwali, they have little effect.

Delhi's pollution is driven by more systemic problems, such as poor infrastructure and clogged roads, aggravated by the city's unfortunate geography.

The landlocked city is in a natural bowl and is surrounded by industrial and agricultural hubs.

Without the coastal breeze of cities like Mumbai and Chennai, much of the pollution is set in motion.

In addition, every year, farmers in fertile neighboring countries are burning in their fields to clean them for the next season.

Known as the burning of straw, millions of tons of crop residues have reached a time of year that usually coincides with Diwali.

CNN's Sreoshi Mukherjee contributed to this story.