Hose blowouts and hose whipping are serious hazards that can cause injuries while workers are pumping concrete.
Air trapped in a delivery line can cause hose blowouts and/or hose whipping. When the air is released, the end of the hose can whip and cause injury to workers in the area. Air in the delivery system itself is not the hazard. But when that air becomes compressed due to a blockage, it stores energy. The risk of a hose blowout or hose whipping happens when that energy discharges.
To minimize the risk during concrete pumping work, ALL personnel should be cautious and maintain a reasonable distance from the discharge hose when:
- Restarting equipment after moving.
- Priming the equipment.
- There is air in the delivery line.
- There is a blockage.
Establish a controlled-access zone around the pumping area to eliminate the potential of the hose striking a worker in case it gets away from the operator.
If you encounter a blockage, move the boom away from the pour to a safe location and re-establish flow before moving the boom back to the pour.
Additional safety measures include:
- Ensure the pump operator has inspected the delivery pipe, and it isn’t cracked or worn.
- Maintain visual contact with the operator or signal person.
- Use a single-ended hose on the discharge.
- Use guide/tag lines to guide the hose while pumping. Do not hug the hose.
- Do not place yourself between the hose and a fixed object.
- Maintain a 20-foot minimum approach distance from all overhead, energized, uninsulated powerlines with voltages of 0.1kV to 350kV.
- For voltages exceeding 350kV, the minimum approach distance is 50 feet.
