Progress has been made improving Bangladesh's safety standards and compensating victims' families, but there's still a long way to go.
Designer Katherine Hamnett says evidence of mistreatment of factory workers in Dhaka shows the fashion industry is "a stinking business".
ITV Exposure investigation uncovers pressures, abuse, violence and safety dangers behind the closed doors of Dhaka's sweatshops.
Primark has shown ITV News details of its strategy to track down the 550 workers who were employed by its subcontractor in the Rana Plaza factory in Bangladesh.
The challenge is made harder by the fact that many of the workers and their dependants have left Dhaka and are spread the "length and breadth of Bangladesh," senior executive Paul Lister said.
Primark, working with the University of Dhaka, has devised a scheme whereby students will travel out to each of the victims in order to assess their level of need.
This data will be entered into touch tablets, which contain software to calculate the level of compensation they can expect.
High-end retailers are sourcing garments from the same factories in Bangladesh as Primark but are charging a higher price, one of the company's senior executives, told ITV News.
Paul Lister said: "If you look at who is sourcing out of Bangladesh, you'll see that clearly Primark sources out of Bangladesh, but actually next door to Primark in any given factory could be a Bond Street retailer, sourcing exactly the same sort of garment, sourcing a T-shirt.
"So ours at Primark would be £5 on our shelf, it could be £60 for the Bond Street retailer, in the same factory, with the same conditions, the same workforce, the same pay, as the £5 Primark T-shirt."
Senior Primark executive Paul Lister has told Business Editor Laura Kuenssberg that the company regularly makes unannounced checks on the 88 factories it uses in Bangladesh in a bid to improve safety standards.
A senior Primark executive, Paul Lister, has told ITV News that it was time for their "competitors to step up to the plate" and compensate victims of the Rana Plaza disaster in Bangladesh
US high street retailer Gap have expressed their sorrow at the news of another deadly factory fire in Bangladesh, in a statement confirming that some of their products have been made with the fabric produced inside the building. In a statement, the company said:
We are deeply saddened by the tragic fire and loss of life at Aswad Composite Mills in Bangladesh, and our thoughts are with the affected workers and families.
At this time, we can confirm that Gap Inc. works with the parent company, Palmal Group, and while Gap Inc. produces no garments at this facility, on rare occasion in the past small quantities of Gap Inc. product have been made with fabric from the mill where the fire occurred.
Gap Inc. continues to make significant long-term investments to improve fire and building safety in Bangladesh with our own safety program and as a member of the Alliance for Bangladesh Worker Safety.
Asda has confirmed that the Bangladeshi factory where the fire broke out is a long-standing supplier to the George clothing range, but that it supplies fabrics rather than finished clothes.
In a statement, George said it believes the industry should "consider whether to extend factory safety programs to this next level of production":
We are deeply saddened by what has happened and our thoughts go out to the families and victims of the accident. George at Asda has a long standing relationship with Aswad Mill, we do source fabric from there and we are working with the owner to ensure we help them however we can.
– statement from george at asda
As part of the Walmart family we have a safety programme that rigorously inspects the factories that make our garments and other products. Typically that program does not extend to the facilities that make materials like fabric for those garment factories. Given the situation in Bangladesh, we, along with Walmart, believe the Government of Bangladesh and the industry should consider whether to extend factory safety programs to this next level of production.