Workers in 19 cities in the U.S. who work at McDonald’s said Monday they filed 28 safety and health complaints with state and federal regulators alleging working conditions that were hazardous leading to severe burns from fryer oil and hot grills.

The complaints have opened another front in a two-year campaign by unions and workers seeking to nearly double the pay per hour to $15 and to improve the working conditions for fast food workers in the U.S.

McDonald’s workers have also claimed wage theft, retaliation for trying to unionize, and racial discrimination are ultimately hoping to hold the company responsible for the actions carried out by its franchisees.

The complaints that have been filed the past two weeks with OSHA – the United States Occupational Safety and Health Administration – and with a number of state authorities have included allegations that the workers had been pressured to clean as well as filter fryer oil while still hot.

These complaints are targeting 19 of McDonald’s franchised restaurants as well as 9 operated by the corporation, but the complaints also claimed many stores did not have basic kits for first aid or any protective gear to ensure the safety of the worker. The allegations include managers telling workers to treat their burns with restaurant condiments such as mayonnaise and mustard.

McDonald’s said its company and franchisees are committed to providing workers with safe conditions at work at all of its 14,000 restaurants in the U.S.

The cities where complaints had been filed included New Orleans, New York City, Kansas City and Philadelphia.

One employee said she had been rushing to meet the demands of the manager to work faster when she fell after slipping on a wet floor at her place of employment in Chicago. Her forearm suffered a severe burn and she damaged nerves in her wrist.

She was later rushed to the hospital by ambulance after her manager said to cover the burn with mustard. She has continued to work at the same restaurant.