Four years ago today, the Savar building, in Dhaka, Bangladesh—known more commonly as the Rana Plaza—collapsed, killing 1,129 people and injuring a further 2,500. Those killed were workers in Bangladesh's booming garment industry, which employs around 3.5 million workers, most of them women. It was Bangladesh's largest man-made disaster, and an entirely preventable tragedy: Cracks had appeared in the building's structure, but the building's owners had ignored them.
Around 80 percent of the workers who died that day were young women aged between 18 and 20. Four years on, conditions remain tough for Bangladesh's garment workforce. Wages are low; sexual harassment is rife; workplace protections are poor. Photographer Claudio Montesano Casillas went inside the factories of Dhaka to document the conditions there.