A new survey says that five years after a garment factory collapse in Bangladesh killed 1,134 people and left thousands injured conditions for the workers toiling in the country's huge apparel industry have improved but much remains to be done.

The survey by the Center for Business and Human Rights at New York University's Stern School of Business found that the largest factories generally have complied with new safety standards set by foreign clothing brands since the 2013 accident.

However workers at about 3,000 of the country's 7,000 factories still face life-threatening risks. The dangerous factories are often smaller, but sometimes subcontract work from larger factories that sign agreements with foreign brands.