The suit claims Southern Industrial, a company ConAgra hired to do natural gas work at the factory, was negligent.
Federal investigators have said a natural gas leak led to the explosion that killed three people a week ago.
Stradley stated in court documents that the employees are seeking $10,000 for injuries they sustained in the collapse.
As of Monday, four burn victims from the explosion were still in critical condition at the NC Jaycee Burn Center in Chapel Hill. A total of seven patients were transported there after the blast.
One victim has been released, while one is in fair condition and another has been upgraded to good.