The United Food and Commercial Workers (UFCW) International Union will represent Packer Sanitation Services Inc (PSSI) workers in Liberal, Kansas, and Mason City, Iowa, according to a statement. The union also reached an agreement with PSSI to offer representation to its workers across the country, the statement said.

PSSI contracts with meatpacking companies to provide cleaning services at slaughterhouses.

The company said it recognized its employees' decision to choose UFCW as their bargaining representative at the plants. PSSI has more than 15,000 employees nationwide at over 400 plants.

In February, the U.S. Department of Labor said the firm paid $1.5 million in penalties for employing more than 100 teenagers in jobs at meatpacking plants in eight states. The children worked overnight shifts and used hazardous chemicals to clean dangerous meat processing equipment such as brisket saws.

Meatpackers including JBS USA and Cargill Inc subsequently said they were ending contracts with PSSI.

"The problems we have witnessed in the industry must firmly remain a thing of the past and we believe that good, strong, union contracts are crucial to protecting all meatpacking and food processing workers," UFCW International President Marc Perrone said.

The UFCW did not immediately respond to questions about combating child labor or how many PSSI employees were joining the union.

(Reporting by Tom Polansek; Editing by David Gregorio)

By Tom Polansek