Abstract: At 5:00 p.m. on July 18, 2017, an employee was assisting with the installation of air conditioning duct work in a residential attic. During work, the employee was starting to become overheated. The cowoker told the employee to go sit in the work truck to cool off in the air conditioning and drink some fluids. Approximately 45 minutes later, the employee was asked to assist another coworker. As the employee exited the vehicle, the coworker observed that the employee's lips were blue. Soon after, the employee collapsed. Emergency services were contacted and, upon their arrival, the employee was determined dead.