After being fined repeatedly for workplace safety violations in recent years, discount retailers Dollar Tree and Family Dollar have reached an agreement with federal regulators to address what inspectors found to be widespread hazards inside their stores.

The Occupational Safety and Health Administration announced Wednesday that the two chains will conduct a nationwide assessment to find the root causes that led to violations for blocked fire exits and other dangers, and develop a plan to resolve them within two years. Dollar Tree acquired Family Dollar in 2015.

As part of the agreement, the company will pay $1.35 million to settle several open inspections and violations. When OSHA informs the company of a hazard in one of its stores, it will have two days to fix the issue or face penalties up to $500,000 under the deal.

Dollar Tree will have to form advisory groups where workers can raise safety concerns, and maintain a hotline where workers can report hazards without fear of retaliation. The company will also hire more safety specialists under the agreement.

Doug Parker, the head of OSHA, told reporters the discount chains had been acting in good faith to address the problems, so he was confident the arrangement would make the stores safer.

Its really intended to address the root causes of these hazards and how the operations of the company to date have contributed to those, Parker said. We believe [Dollar Tree] has proposed to us a plan that is genuinely going to make a significant impact on improving safety and health for its workers.

Mike Creedon, Dollar Trees chief operating officer, said in a statement that the company was committing to substantial safety policies, procedures, and training.

Having worked with OSHA over the past several months on this agreement, we now look forward to continuously improving our programs to keep our associates safe, Creedon said.

Customers whove shopped in dollar stores are familiar with the huge stacks of unboxed merchandise that often litter the aisles and make it hard to navigate. OSHA has hit the retailers with numerous fines and publicized them for impeding exits, unsafely storing boxes and cutting off access to fire extinguishers and electrical panels.