Abstract: At approximately 10:00 a.m. on June 29, 2017, several employees were at a construction site for a new animal exhibit in a zoo. The project included the construction of steel frames using reinforcing steel bars to create a form work for artificial rock scape. Concrete was shot onto the form work via a two inch diameter hose from the concrete pump. Employees used the concrete to sculpt a rock formation. Employees also handle the concrete pump hoses and moved one of the hose to the location where concrete was to be applied to steel frames. There was uneven terrain with mounds and low spots and path ways around the area of the construction site. Employees were assisting with moving the concrete pump hoses to deliver concrete to the steel frames, while another crew built steel frames for other rock formations. The hoses range in length from 50 ft to approximately 300 ft. At approximately 10:00 a.m., the crew had just relocated the 300 ft hose from one location which was the farthest out from the pump, and relocated the hose to a different work area closer to the pump, about 100 feet closer. The hose was laid on the ground in the work area for the nozzle man to apply the concrete to the steel forms. During the concrete pumping activity, the hose got clogged at about 150 feet out from the pump. Employees made the pump operator aware of the blockage. The pump operator stopped the machine and reversed the motor to relieve the pressure in the hose, but not before the hose ruptured. The hose tore into two pieces. The pressure applied to the material to pump it through the hose length caused the hose to whip around as the pressure was relieved, spraying out concrete debris. The ruptured hose and projected concrete debris struck several employees.. The employees suffered bruises and one worker sustained a mild concussion. No employee was hospitalized for more than 24 hours. All employees were released from the hospital the next morning.