A building owner wants us to drill a large number of holes in concrete walls between offices so they can network computers. How can we control slurry spray when drilling these holes so workers can remain in their offices?
Skilled operators can drill wall cores in occupied areas with little disruption to the occupants and building contents. One coring specialist says that spray of drilling slurry usually occurs when the core barrel starts to cut the concrete and when the core is removed. He uses minimal cooling water until the cut is established. To catch water flowing out the hole, he uses duct tape to make a combination flange and funnel and diverts the cutting slurry into a bucket. At the end of the cut a moist ring usually appears at the core location just before the barrel cuts through. If possible, have someone watch for this sign and notify the driller to stop. The driller can then tap on the core from the intact side and break it loose. If the driller must work alone, he or she should cut to a depth less than the wall thickness then break out the core.