CHICAGO (CBS) — A mobile medical tractor manufacturer has been cited by federal workplace safety authorities more than three months after a worker was killed during his first day on the job in south suburban Monee.

Authorities responded July 5 to Advanced Mobility in the 6300 block of Emerald Parkway in Monee, according to Monee police and the Cook County medical examiner’s office.

Leo Micheletto, 58, an electrician, was working underneath a semi trailer when another worker inadvertently punctured a hydraulic line, and the trailer fell onto Micheletto’s head and chest, authorities said.

Micheletto, of the 7500 block of West Silo Drive in Frankfort, was taken to Franciscan St. James Health in Olympia Fields, where he was pronounced dead at 10:47 a.m., according to the medical examiner’s office. An autopsy found he died of multiple blunt-force injuries from the industrial accident.

The Occupational Safety and Health Administration investigated the death and found the company failed to ensure the use of safety pins on the trailer’s front hydraulic leg stands, and the use of rear stationary jacks to prevent the trailer from falling. OSHA cited the company for one serious safety violation.

The death also prompted an inspection of the company’s University Park facility, which was cited for six serious safety violations.

The company faces proposed penalties of $58,792, according to OSHA.

“I can’t imagine the incredible loss this man’s family and friends felt when his first day on the job ended tragically,” OSHA area director Kathy Webb said in a statement.

“Advanced Mobility could have prevented his death by using simple safety devices like safety pins and jacks, and implementing procedures to ensure hydraulic energy was isolated. This employer failed in its responsibility to take all necessary precautions to protect workers on the job,” Webb said.

Advanced Mobility, based in Louisville, Kentucky, specializes in mobile medical trailer manufacturing and refurbishing.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2016. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)