Setting the Record Straight on Concrete Pumping Stability
To the editor:
Regarding the story, “Sudden Concrete Pump Truck Shifts Hurt Workers,” ENR 9/05, p. 18, about the OSHA penalty proposed against Roy Rock LLC, we found it curious that the story didn’t mention the ASME B30.27 Safety Standard for the Material Placing Systems and only mentioned the American Concrete Pumping Institute’s bulletins. The OSHA Review Commission judge mentions both but misreads or misinterprets them and unfortunately fails to follow the ASME standard in making his decision.
The entire point of the responsibilities section of the ASME standard is to make the people who have the jobsite information and control do their part to prevent accidents.
In the Roy Rock case, the pump was positioned at a spot that resulted in the full force of the outrigger being placed on a hidden water pipe, with backfilled dense-grade aggregate. The pipe and surrounding soil couldn’t withstand the outrigger force and it sank to a new position, causing the outrigger to suddenly sink. The resultant out-of-level boom position caused the boom to swivel downhill and the attached hose struck a worker, knocking him unconscious. He recovered.
The project’s concrete contractor, Roy Rock, was the pump owner, user and pour supervisor. But the site supervisor (the general contractor) also has the critical responsibility of the site conditions under the standard.
The ACPA bulletins cited by the OSHA judge clearly states that the operator, on arriving at the jobsite, should “always check in with the contractor. Talk with the superintendent or foreman regarding where to set up safely. The contractor needs to supply a safe set-up area where the soil is capable of supporting the outriggers and there are no voids, pipes or other hidden dangers.” In this case, the general contractor failed to do its job.
Nor are operators expected to make calculations at the jobsite. The ground has many different load-bearing capacities, and boom trucks all impose a different force on the soil. The bottom line, according to the bulletin, is “the greater the force imposed on the soil, the larger” the area of loose materials needed to support the equipment must be.
On the project where the accident occurred, more than one company failed, starting with the general contractor, which selects the spot for the pump because only the general contractor knows where there will be other traffic, other activities and buried items. The pump user and pour supervisor, Roy Rock, didn’t prepare the general contractor for what would be needed or verify that the selected spot was adequate.
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However, Roy Rock followed the instructions in the ACPA safety bulletin. The contractor specifically led Roy Rock employers to the set-up spot, jacked the outriggers, watched for sinking and all was well as far as Roy Rock knew. In our reading of the judge’s decision to uphold the penalty against Roy Rock, none of the entities knowing the location of the buried pipe relayed the information to Roy Rock.
It’s troubling that OSHA would not accept the ASME B30 safety standard as the “rule” when determining fault. But the ACPA bulletin sums up the operator’s dilemma: “Unless an operator has X-ray vision, there is no way he can tell if he is setting up over a hidden void.” Operators do not have X-ray vision, and only site management could show him where the buried voids are hidden.
Robert Edwards
Former Chair
ASME B30 Committee Member
American Concrete Pumping Association
Minneapolis, Minn.
Christi Collins
Executive Director
American Concrete Pumping Association
Lewis Center, Ohio
