Abstract: At 11:15 a.m. on November 18, 2019, an employee who worked as a manager for a heavy equipment rental service was assisting a coworker (a Driver) unloading equipment from a flatbed trailer. The coworker had brought two articulating boom lifts that had been rented out by customers to the main yard. The coworker parked the trailer in the yard and unchained one of the boom lifts in the rear when the employee offered to help. As the coworker started unchaining the second boom lift the employee stepped into the basket of the first boom lift, a Genie model Z-30/20N, to back it off the trailer. The lift was in the lowered stowed position and the basket was positioned toward the front of the trailer in relation to the base of the equipment. The employee did not realize the dove tail ramp of the trailer was not down in the unloading position. As the employee reversed the lift off the rear edge of the trailer the boom lift fell. The rear wheels went into the air and the basket swung upward ejecting the employee. The basket came to rest approximately 15 feet in the air. The employee landed approximately 30 feet away on the asphalt. He broke four teeth, fractured both wrists and elbows, and fractured a right knee and was hospitalized for five days.