Concrete Coring JHA (Job Hazard Analysis / Activity Hazard Analysis)
Updated 2026-06-23
A Concrete Coring JHA (Job Hazard Analysis / Activity Hazard Analysis) is the plan that keeps the coring crew from breathing silica, hitting embedded utilities or post-tension cables, or being struck by a heavy core that drops through the slab. Concrete coring drills clean round holes through concrete slabs and walls for penetrations, using a core drill with a diamond bit, and the operation carries the same hidden-hazard and silica risks as all concrete cutting. This guide walks through building a Concrete Coring JHA that names the silica, embedded-utility, and core-fall hazards and assigns the scanning, wet-coring, and core-control measures that hold up in the field.
Why concrete coring needs its own JHA
Concrete coring uses a core drill — a motor driving a hollow diamond-tipped bit — to bore clean round holes through concrete for pipe, conduit, and other penetrations. The drill is mounted on a rig anchored to the surface, and the operation generates a cylindrical core that must be removed. The hazards mirror concrete saw cutting: respirable silica from the drilling, the risk of coring into embedded electrical conduit, post-tension cables (which release violently if cut), water lines, and rebar, the heavy core dropping through the slab onto the level below, and the drill rig and electrical/water hazards. Because coring blindly penetrates concrete that may hide utilities and generates silica, it warrants a dedicated JHA.
Breaking concrete coring into steps
The steps for a Concrete Coring JHA follow the core:
- Identify and scan for embedded utilities and post-tension cables
- Confirm the core location is approved and structurally acceptable
- Set up dust/water control (wet coring or vacuum)
- Anchor the core drill rig securely
- Barricade the area below the core location
- Drill the core, managing water and the rig
- Control and remove the core
- Clean up slurry and finalize
Each step carries a hazard, and the scanning for embedments and the silica/core-fall control are where the most serious risks are managed.
The hazards step by step
Embedded utilities and post-tension cables
Coring blindly penetrates concrete that can hide live electrical conduit, post-tension cables, water lines, and rebar. Coring into electrical conduit electrocutes, coring through a post-tension cable releases its enormous tension violently, and coring water lines floods. The controls are scanning the concrete with ground-penetrating radar or other detection before coring, reviewing structural and utility drawings, locating and avoiding post-tension cables (not coring near them without engineering involvement), and de-energizing or isolating utilities that may be embedded. Scanning before coring is essential on any slab or wall that could contain embedments.
Respirable silica
Coring concrete generates respirable crystalline silica. The controls follow the silica standard — wet coring, which uses water to suppress the dust at the bit (and is the common method for core drilling), or vacuum dust collection for dry coring, with respiratory protection where dust remains. Wet coring is highly effective for silica control.
Falling core
The core — a heavy cylinder of concrete — can drop through the slab onto the level below when the cut is completed, and can fall as it is removed. The controls are barricading and clearing the area below the core location, controlling the core (core catchers or supporting it) so it does not free-fall, and planning for the core's removal before the cut is completed.
Rig anchoring and water/electrical hazards
The core drill rig must be anchored so it does not spin or pull free, and coring combines water with electrical equipment. The controls are anchoring the rig securely (the high torque can spin an unanchored rig), GFCI protection for the electrical drill in wet conditions, managing the water, and keeping electrical connections out of the water/slurry.
A simple Concrete Coring JHA structure
| Step | Hazard | Control | Standard |
|---|---|---|---|
| Scan concrete | Embedded utility / PT cable | GPR/scan, review drawings, locate post-tension cables | OSHA 1926.416 |
| Set up dust control | Silica | Wet coring or vacuum collection, respirator | OSHA 1926.1153 |
| Anchor rig | Rig spin / pull-free | Anchor rig securely for the torque | OSHA 1926.300 |
| Barricade below | Falling core | Clear and barricade the area below the core | OSHA 1926.501 |
| Core / manage water | Electrical shock | GFCI for wet conditions, manage water and slurry | OSHA 1926.404 |
| Control the core | Falling core | Core catcher, support, plan removal before cut completes | OSHA 1926.250 |
Scanning and wet coring
A Concrete Coring JHA rests on scanning before coring and wet coring, the same two controls that govern all concrete cutting. Scanning addresses the embedded-utility hazard — coring blindly into concrete can hit live conduit, water lines, or a post-tension cable, the last of which releases enormous tension violently — so the concrete is scanned and the post-tension cables located before coring, with engineering involvement for any core near them. Wet coring addresses the silica — water at the bit suppresses the respirable silica that coring generates, and it is the common and effective method. A JHA built on scanning before coring and wet coring, with the core controlled against falling and the rig anchored, addresses the hazards that make concrete coring more dangerous than a clean round hole suggests.
From the field: what actually goes wrong
In fourteen years across federal, heavy civil, and industrial projects, concrete coring carries the same hidden hazards as concrete saw cutting, and the most serious is coring into a post-tension cable. A post-tension cable holds enormous tension, and coring through one releases that energy violently — it can be fatal. The defense is scanning the concrete and locating the cables before coring, and never coring into a post-tension slab without knowing where the cables run and involving the structural engineer. Coring into live electrical conduit is the other embedment hazard, electrocuting the operator, and scanning plus utility isolation addresses it. The principle is the same as all concrete cutting: you do not core into concrete you have not scanned.
The silica and the falling core are the other hazards. Coring generates respirable silica, controlled by wet coring — which is the common method and suppresses the dust effectively — far better than relying on a respirator alone. The falling core is the coring-specific struck-by: the heavy concrete cylinder can drop through the slab onto the level below when the cut completes, so the area below is barricaded and cleared, and the core is controlled or caught. On the projects I have run, the rig anchoring also matters — the high torque can spin an unanchored rig and injure the operator — and GFCI protection is essential given the water and electrical combination. The JHA that scans before coring, cores wet, controls the core, and anchors the rig is the one that protects the coring crew.
The bottom line
A Concrete Coring JHA names the silica, the embedded-utility, and the core-fall hazards with specific controls — scanning and locating post-tension cables before coring, wet coring for the silica, barricading below and controlling the core against falling, and anchoring the rig with GFCI protection. The hidden embedments and the silica are what make coring dangerous beyond the clean hole it produces. The JHA built on scanning and wet coring is the one that protects the crew.
Frequently asked questions
Why must concrete be scanned before coring?
Coring blindly penetrates concrete that can hide live electrical conduit, post-tension cables, water lines, and rebar. Coring into electrical conduit electrocutes, coring through a post-tension cable releases its enormous tension violently and can be fatal, and coring water lines floods. Scanning with ground-penetrating radar and reviewing drawings before coring prevents these strikes.
How is silica controlled during coring?
By wet coring — using water at the bit to suppress the respirable silica — which is the common method for core drilling and is highly effective, or by vacuum dust collection for dry coring, with respiratory protection where dust remains, following the silica standard.
What is the falling-core hazard?
The core is a heavy cylinder of concrete that can drop through the slab onto the level below when the cut completes, and can fall as it is removed. Controls are barricading and clearing the area below the core location, controlling the core with a core catcher or support so it does not free-fall, and planning the core's removal before the cut is completed.
Why must the core drill rig be anchored?
The core drill develops high torque, and an unanchored rig can spin or pull free, injuring the operator. The rig is anchored securely to the surface for the torque, and GFCI protection is used because coring combines water with the electrical drill, with connections kept out of the water and slurry.
Related JHAs
- Core Drilling and Concrete Saw Cutting JHA — related coring and cutting hazards
- Concrete Placement JHA — the concrete being cored and its embedments
- Electrical Work JHA — isolating embedded electrical conduit
- Hand and Power Tool Safety JHA — drill and tool safety
Written by Mustafa Tok, CSP, ASP, CHST — OSHA Authorized Outreach Trainer with 14+ years of international construction safety experience across federal, heavy civil, and industrial projects.