CHICAGO (Reuters) -Archer-Daniels-Midland Co intentionally failed to test and maintain safety systems on its grain equipment for years, which contributed to an explosion that immolated a worker and put him in a coma last year, according to a lawsuit filed against the company.

The explosion was part of a string of safety incidents at ADM facilities in Decatur, Illinois, site of the global grain trader's North American headquarters.

ADM on Thursday declined to comment on the lawsuit.

The company's shares have been under pressure this year from a global glut of grain supplies, and it is also facing U.S. government investigations related to accounting irregularities.

The lawsuit, filed on Wednesday in Macon County Circuit Court in Illinois, alleges that worker Antonio McElrath was in a Decatur facility known as the West Plant in April 2023 when a supervisor told him to shut down a grain "leg" tube that started smoking.

An explosion occurred when the tube was opened, and McElrath was standing in its direct path, according to the lawsuit.

McElrath, now 44, was in an induced coma for two to three weeks following the accident, his attorney Timothy Shay said. "He has suffered significant injuries and is still in recovery."

Investigators with the U.S. Department of Labor's Occupational Safety and Health Administration found that ADM failed to inspect or test critical safety systems in the explosion that injured McElrath and two other workers.

ADM had fire and explosion suppression systems in place to prevent problems and keep workers safe, but the systems were not working, the lawsuit alleges.

ADM's sprawling grain and oilseed processing complex in Decatur also suffered dust explosions in 2018 and 2019, fires in 2019, and a smoldering event this summer at the West Plant, according to the lawsuit.

Separately, workers were injured from an explosion at the site's East Plant in September 2023. And on Monday, an industrial fire broke out at ADM's sorbitol production department of its East Plant, according to the Decatur Fire Department.

ADM has focused on safety efforts companywide, ADM spokeswoman Jackie Anderson said in an email statement late on Thursday.

At its Decatur complex over the past year, the company has hired process safety engineers and taken other steps to improve safety in its processes, among other steps, Anderson said. "We are fully committed to learning and improving when an operational event occurs so that it does not happen again."