Concrete pumping is an economical and efficient means of placing concrete for most concrete placement jobs in the construction industry today. Knowing how to safely work with the concrete pump on the jobsite will help to ensure you have a successful and profitable pour.
Hose whipping accidents are one of the most common accidents associated with operating a concrete pump. Air trapped in the delivery system is a common cause of hose whippings as a result of higher horsepower and pump pressures available in today's equipment. Air can be introduced into the delivery system by various means: when the pump is started initially; restarting after a move; allowing the concrete level to fall below the valve; after removing a blockage; or allowing concrete to free fall after the pump is shut off.
The American Concrete Pumping Association's (ACPA) Safety Bulletin: Hose-Whipping Accidents explains that “air in the delivery system by itself poses no particular hazard; e.g. whenever delivery system is cleaned out, it's full of air. It's only when the air is compressed, thereby storing energy, that a hazard is created.”
Injuries to placing crew personnel have occurred when this trapped air is momentarily compressed and then released causing the hose to whip violently. To avoid injury, the ACPA recommends that all personnel should remain a prudent and reasonable distance from the end of the delivery line until air is exhausted from the system and concrete is free flowing once more.
The ACPA Safety Bulletin describes how to determine what that safe distance is for personnel to stand. “The end-hose movement area is defined as the area within the radius of the last flexible (nonsteel) piece of delivery system. For example, if 10 feet of rubber hose is attached to a pipeline, personnel standing more than 10 feet away from the point of attachment are outside of the end-hose movement area.”
Debris coming from the hose during release of trapped compressed air also can be a hazard, so personnel should always wear protection equipment such as a hard hat and eye protection.
More information is available on the causes and effects of hose whipping accidents at www.concretepumpers.com, including a free PDF download of the ACPA's Safety Bulletin: Hose-Whipping Accidents. It also includes pertinent information that operators, laborers at the pump, placing crews, ready-mixed concrete truck drivers, and contractors should know about hose safety.
When every person on the job understands what can occur when air is compressed in the hose and the proper precautions are made, a successful and profitable concrete pour results
Editor's Note:In February's column on cement-related skin conditions, it's important to note in the cases of caustic or cement burns, it may take several days before this “burn” is felt, thus offering no warning to stop what you're doing on the job. Burns are serious and can cause lifetime scarring. Wear protective equipment at all times when handling concrete products.
Mike Cusack is the vice president of operations for Conco Pumping, Concord, Calif. He can be reached at 925-687-6040 or firstname.lastname@example.org. The American Concrete Pumping Association can be reached at 606 Enterprise Drive, Lewis Center, Ohio 43035 or at 614-431-5618.