Core Drill Tips
Tips on How to Use Your Core Drill Safely
The combination of tough working conditions, operating concerns, and health considerations present unique challenges to core drilling. Whether you are coring a passageway through a brick wall, or about to undertake a massive concrete removal project, adopting some simple procedures into your standard operating procedures will help you meet the challenges that these tough work sites bring.Pre-check All Equipment Prior to the Job
Core drilling equipment manufacturers provide information on how operators should inspect their equipment prior to start. The key point in all instructions is “Do not use any tools if damage is suspected.”
Since core drilling is often performed in tough conditions, operators should be instructed to perform a quick check before each set-up. Don’t assume that the equipment checked at your shop is in the same condition when it arrives at the coring site. The equipment could have been damaged in transport to the worksite.
Also, a quick inspection of your core bits, adapters and extractors is a good idea. These durable tools can be chipped, cross-threaded, or bent. Well maintained tools will help keep the core holes straight, reduce the chance of binding, and ensure operator safety.
Double check that the core hole that needs to be drilled matches the capabilities of the core drill assembly on hand. For example:
The job specs call for a series of 2” diameter holes. So, you’ve brought your hand-held core drill assembly. But as you’re unloading the gear, the general contractor now wants 3” holes. This slight change order could result in a change of equipment. You probably should head back to the toolbox and select a core drill assembly with a larger motor capacity and a drill stand or rig that properly secures it for the larger holes.
It’s important to ensure the drill has enough power to properly drill the larger hole. This will be the safer and more productive choice.
Inspect the Drill Site
Have a plan of what you are going to drill. Consider drilling a pilot hole prior to coring, and check with the jobsite supervisor to identify any electrical lines, gas lines or other hazards that may be in or under the slab or in or behind the wall that will be cored.A wise investment is a hand-held metal detector with ground penetrating radar (GPR) that can detect pipes, conduits, post tension cables, live wires, and rebar. Some high-end GPR units can get readings more than 38" into a concrete or masonry slab or wall. Never skip this important step! Randomly drilling into a wall or slab is reckless and potentially dangerous.
If you’re involved in a project that features demolition, double check with the engineer of record prior to drilling. Previous work at the site may have additional unforeseen stresses on components affecting the structure’s integrity.
When coring through walls and floors that are above ground level, confirm where the loosened material will release. Try to barricade the fall area by the through-hole and when possible, have a worker guard that area.
Bring along enough portable lighting devices so the core drill operator can clearly see the unit’s core operation.
When coring through walls and floors that are above ground level, confirm where the loosened material will release. Try to barricade the fall area by the through-hole and when possible, have a worker guard that area.
Bring along enough portable lighting devices so the core drill operator can clearly see the unit’s core operation.
Secure Your Core Drill Assembly
To avoid any unnecessary bit binding, the core drill’s assembly must be static. Secure the rig’s base and rig stand to prevent movement during coring operations. You can either use mechanical anchors or base vacuums to secure the rig to the floor.
If you opt for a vacuum anchorage, confirm that the surface is smooth, and the vacuum gasket is in good working order. Remember, if you opt to use a vacuum, you probably should have some mechanical anchors on hand as a backup in case the power were to be cut off or shut down during drilling.
Regardless of the type of attachment in use, professionals often rely on additional safety chains to minimize the risks for accidental drill slippage.
When plugging the power unit into an outlet or generator set, opt for heavy-gauge extension cords. Be sure to also check that the electrical system is properly grounded. These are standard checkpoints for any drilling application.
Regardless of the type of attachment in use, professionals often rely on additional safety chains to minimize the risks for accidental drill slippage.
Electrical Safety
Core drills often use water and electricity to get the job done. This potentially dangerous combination requires careful considerations. If this is a standard practice opt for power units equipped with built-in ground-fault circuit interrupters (GFCIs). Also check to see if the power units are UL listed as a system.When plugging the power unit into an outlet or generator set, opt for heavy-gauge extension cords. Be sure to also check that the electrical system is properly grounded. These are standard checkpoints for any drilling application.
Hydraulic System Safety
There are a few additional safety considerations if your core drill’s power source is hydraulic. Start by checking the power unit’s hydraulic fluid level. If you have extra fluid on hand, be sure to store it in approved containers. Make sure all hoses are connected for correct flow direction to and from the tool being used. When the unit is powered on, but before operation, confirm that all hoses are free from cuts and all fittings are secure.Worker Personal Protection Equipment
Your core drilling operations will take you through a wide array of settings – from dark, damp, and adverse conditions to extremely hot outdoor tarmacs. It’s important to be ready for all these environments, in addition to having the standard eye, hearing, and hand protection supplies.In addition to jobsite exposures, your crew will encounter additional hazards from the act of core drilling. If you are dry drilling, you’ll need to mitigate any fugitive dust. All shrouds must fit securely at the core hole’s collar to capture debris. Double check the dust extraction system’s HEPA filter. As required, be sure that all respirators fit properly, and use a half-face respirator, or a unit fully rated for the task at hand.
If you are wet drilling, plan how you will contain the excess water and slurry. You might need to use tube sorbents to direct the slurry and process water to a containment vessel.

Have the proper tools and vacuums on hand to collect any dust left from fried out slurry and be sure to dispose of slurry as per your local regulations.
Your White Cap branch has access to all the maintenance and safety supplies you’ll need on all types of core drilling jobs, along with the support of local experts who can advise you on the specific conditions in your area.