Abstract: At approximately 10:00 a.m. on December 15, 2023, an employee working for a marine cargo terminal had been operating a Kalmar Reachstacker for about 2.5 hours when he told Coworker #1 (immediate supervisor) that he was feeling ill and asked for permission to leave work. After telling Coworker #1, he followed company protocol by reporting to Coworker #2 (union foreman), Coworker #3 (shift supervisor) and Coworker #4 (paymaster). After being authorized to leave, the employee went to his car. At about 11:30 a.m., other coworkers including Coworker #5, the employee's relative (brother-in-law), that were on their way to go to lunch, noticed the employee's car was running in the company parking lot. Coworker #5 and the other coworkers approached and knocked on the employee's car windows, which were tinted, but there was no response. Coworker #6, employer representative in charge of safety, arrived at the area and gave the instructions to break the car window. Once they could get into the car, Coworker #7 checked the employee, but he did not have a pulse. Simultaneously, Coworker #8, the security guard, called 911. Paramedics arrived and certified that the employee had died on the scene. Police officers arrived and prepared a report. Later, personnel from Technical Services of the Puerto Rico Police Department, and from the Funeral Home picked up the employee. The employee had died from a heart attack.