Under a sky darkened by thick, black smoke, hundreds of thousands of laborers across South Asia work at brick kilns.
These men, women and children perform difficult work in extreme heat. Conditions today are much like they were many centuries ago.
Brick kilns produce heat for bricks, which are used to build homes, offices and factories. Yet the kilns are among the most notorious sources of air pollution in South Asian countries.
In 2015, a powerful earthquake struck Nepal.About 9,000 people were killed. The quake destroyed homes and many other things, including about 30 percent of the country’s brick kilns.
For environmentalists, the destruction gave them a chance to clean up at least one part of the dirty industry.
The International Centre for Integrated Mountain Development operates a program called the Brick Kiln Initiative. It found a way to design the brick kilns and build them differently so they produce less pollution.
“We have changed three things," explained Bidya Banmali Pradhan, who directs programs for the initiative. "One is more resistance to earthquake. The second is less polluting, and the third is energy efficiency.”
“我们已经对其进行了三种改变，”该倡议项目负责人比迪亚·班马里·普拉汉(Bidya Banmali Pradhan)解释说。一个是对地震的抵抗力增强。第二是减少污染，第三是提高能源效率。
The Brick Kiln Initiative proposed placing bricks inside the kilns in a zig-zag design. This way, the heat moves through the holes more efficiently so that the coal burns completely and produces less dirty air.
“I adopted this to clean up the environment," kiln owner Raj Kumar Lakhemaru said. “I think this is now being adopted by others across the country.”
Pollution from kilns was cut by 60 percent. And more importantly for the kiln owners, it reduced coal use by half.
“Since we adopted this zig-zag method... there is less pollution, we [are] using less coal and getting better bricks, faster," said Mahendra Chitrakar, president of the Federation of Nepal Brick Industries.
Most of the 100 brick kilns in the Kathmandu Valley have already been changed.
The Federation of Nepal Brick Industries hopes to change all of the country’s brick kilns in the next two to three years.
Brick makers from Bangladesh, India, Nepal and Pakistan met in Kathmandu earlier this year to discuss the new design.
I’m Susan Shand.