Job Hazard Analysis: Concrete demolition

A general example for this task. Your JHA should reflect your crew, equipment and site — review it with a competent person before work starts.

Steps, hazards and controls

1. 1. Survey the slab and plan the work

   • Cutting or breaking into buried or embedded electrical lines, gas lines, or water pipesHigh
     • Call 811 and wait for utility marks before any cutting or breaking.
     • Have the competent person shut off, lock out, and tag any power to circuits running in or under the slab.
     • Scan the slab with GPR or check plans for conduit and pipes; mark them with paint.
     • Use only tools with insulated handles and GFCI-protected cords.
   • Post-tension cables in the slab snapping out under high tensionHigh
     • Look for tendon pockets or PT stamps at slab edges; if found, stop and get an engineer's plan before cutting.
     • Keep everyone out of the line of the cables until they are de-tensioned.

2. 2. Set up the work zone, barricades, and equipment

   • Workers struck by passing vehicles or the public walking into the work areaMedium
     • Put up cones, barricades, and caution tape at least 10 ft around the work area.
     • Post 'Danger – Demolition – Keep Out' signs at every entrance.
     • Use a trained flagger when work is next to a street or driveway in use.
     • Wear a hi-vis vest at all times.
   • Back and shoulder strain unloading breakers, saws, and air compressor hosesLow
     • Use a hand truck or the skid steer to move breakers and saws.
     • Two-person lift for anything over 50 lb.

3. 3. Saw-cut the edges with a water-fed cut-off saw

   • Breathing silica dust from cutting concreteHigh
     • Use only saws with a working water feed; keep water flowing on the blade the whole cut.
     • Never dry-cut concrete.
     • Keep other workers upwind and out of the dust and slurry area.
     • Indoors or when cutting over 4 hours a shift with a handheld saw, wear a respirator with APF 10 or higher as listed in the silica exposure control plan.
   • Saw kickback or contact with the spinning bladeHigh
     • Check the blade guard, blade rating, and arbor before starting; replace cracked or worn blades.
     • Keep the cut open with wedges so the blade does not pinch.
     • Hold the saw with both hands and stand to the side of the blade, never behind it.
     • Let the blade stop fully before setting the saw down.
   • Carbon monoxide from gas saws used indoors or in tight spacesMedium
     • Use an electric or hydraulic saw indoors instead of a gas saw.
     • If a gas saw must be used inside, open doors, run fans, and use a CO monitor.
     • Stop work and get fresh air if you feel a headache, dizziness, or nausea.

4. 4. Break the concrete with breaker hammers or a skid steer breaker

   • Flying concrete chips hitting eyes, face, or nearby workersMedium
     • Keep everyone not breaking at least 15 ft away; 25 ft from a skid steer breaker.
     • Wear safety glasses plus a face shield while breaking.
   • Silica dust from breaking concreteHigh
     • Spray water at the point of impact with a hose or water-fed attachment while breaking.
     • Run the skid steer with the cab door closed and the air filter clean.
     • Wear a respirator with APF 10 or higher for handheld breaking indoors or as listed in the silica plan.
   • Loud noise and hand-arm vibration from 60–90 lb breakersHigh
     • Use low-vibration breakers and let the tool's weight do the work; do not lean on it.
     • Rotate operators every 30 minutes.
     • Wear earplugs and earmuffs together and anti-vibration gloves.
   • Breaker point or slab pieces falling on feet; air hose whipping if it comes looseMedium
     • Pin all air hose connections with whip checks and safety clips.
     • Shut off air and bleed the line before changing points.
     • Wear steel-toe boots with metatarsal guards.

5. 5. Cut rebar and wire mesh

   • Sparks from abrasive saw or torch starting a fireMedium
     • Use hydraulic rebar cutters or bolt cutters instead of a torch when possible.
     • Clear wood, fuel cans, and trash 35 ft from the cut.
     • Keep a charged fire extinguisher within reach.
   • Impalement or cuts from sticking-up rebar endsMedium
     • Cut rebar flush or bend it down right away.
     • Put rebar caps on any ends that stay up.
     • Wear cut-resistant gloves when handling rebar and mesh.

6. 6. Load debris into the dumpster

   • Workers struck or run over by the skid steerHigh
     • Only trained, authorized operators run the skid steer.
     • Keep ground workers out of the machine's swing and travel path; make eye contact with the operator before approaching.
     • Check that the backup alarm works; use a spotter when backing near people or the dumpster.
     • Wear seat belt and keep the lap bar down while operating.
   • Back strain and pinched fingers lifting concrete chunks by handMedium
     • Break pieces small enough to lift easily, under 50 lb, or use the skid steer bucket.
     • Lift with your legs, keep the load close, and do not twist.
     • Wear leather work gloves.

7. 7. Clean up the area and put away tools

   • Silica dust stirred up during cleanupMedium
     • Wet down dust and slurry, then shovel or use a HEPA vacuum.
     • Never dry sweep or blow dust with compressed air.
     • Wash hands and face before eating, drinking, or smoking.
   • Trips and falls over hoses, cords, rubble, and open slab edgesLow
     • Coil hoses and cords and remove rubble as you go.
     • Barricade any drop-offs or holes left open overnight.