Job Hazard Analysis: Backfill and compaction

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. Pre-task check: competent person inspects the trench, protective system, spoils, and weather before anyone enters.

   • Trench wall collapse from rain, vibration, cracks, or water in the trenchHigh
     • Competent person inspects the trench at the start of each shift and after every rain or change in conditions.
     • Confirm the trench box, shoring, or sloping is in place for any trench 5 ft deep or more before anyone enters.
     • Keep spoil piles and backfill stockpiles at least 2 ft back from the trench edge.
     • Pump out standing water before work; nobody enters if the competent person says stop.
   • Falling into the open trench while walking the edgeMedium
     • Set barricades or warning line around the open trench.
     • Use a ladder within 25 ft of every worker in trenches 4 ft deep or more, extending 3 ft above the edge.

2. 2. Set up equipment and work zone: stage backfill, park the excavator or loader, set traffic control, and fuel the compactor.

   • Workers struck by backing loader, dump truck, or skid steerHigh
     • Lay out a one-way haul route that keeps trucks away from the trench edge and the crew.
     • Check that backup alarms work; use a spotter when the operator cannot see behind the machine.
     • Wear a high-visibility vest; never walk behind a machine without eye contact with the operator.
   • Fire from spilled gasoline while fueling a hot compactorMedium
     • Shut off the engine and let it cool before fueling.
     • Use an approved safety can, fuel away from the trench, and keep a fire extinguisher nearby; no smoking.

3. 3. Place backfill into the trench in lifts with the excavator or loader bucket.

   • Worker in the trench struck or buried by dumped materialHigh
     • Everyone climbs out of the trench or stays inside the trench box away from the dump zone while the bucket is placing material.
     • Operator places material only on the signal of one designated person.
     • Never stand under a raised bucket or swinging load.
   • Machine tipping or edge collapsing under equipment weightHigh
     • Keep tracks and wheels back from the trench edge; use stop logs or barricades where equipment works close.
     • Operator wears the seat belt and keeps the bucket low when traveling.
   • Damage to buried or newly laid utilities from heavy rock or dropped materialMedium
     • Hand-place or lightly place select bedding around pipe before machine backfilling; keep rocks out of the first lifts.
     • Keep 811 locate marks visible and hand-dig near marked lines.

4. 4. Compact each lift with the jumping jack or vibratory plate compactor.

   • Carbon monoxide buildup from gas compactor exhaust in a trenchHigh
     • Use an electric or battery compactor or a remote/excavator-mounted compactor in deep or narrow trenches when available.
     • Test the air with a CO monitor in trenches over 4 ft; get out if it alarms.
     • Rotate operators and take fresh-air breaks; get out if you feel headache, dizziness, or nausea.
   • Crushed feet or loss of control of the compactorMedium
     • Inspect the compactor before use: guards, handle, throttle, and shutoff working.
     • Keep both hands on the handle and keep other workers out of the compactor's path.
     • Wear steel- or composite-toe boots.
   • Noise and hand-arm vibration from the compactorMedium
     • Rotate the compactor operator about every 30–60 minutes.
     • Wear earplugs or earmuffs while the compactor runs and anti-vibration gloves.
   • Vibration loosening trench walls near the compactorHigh
     • Compact only inside the protected area of the trench box or shoring.
     • Watch for cracks or sloughing; stop and get out if walls move.

5. 5. Move or pull the trench box and shoring up as backfill rises.

   • Cave-in of unprotected walls when the box or shoring is raisedHigh
     • Pull the box or shoring only from outside the trench, in stages, with no one inside the unprotected section.
     • Remove shoring from the bottom up as backfill is placed, following the manufacturer's tabulated data.
   • Struck by swinging trench box or rigging failureHigh
     • Inspect chains, shackles, and lifting points before each pick.
     • Keep everyone clear of the swing radius; use tag lines and one signal person.

6. 6. Final grading and density testing of the top lift.

   • Testers and laborers struck by equipment during gradingMedium
     • Stop equipment and set the bucket down while the tester or grade checker is in the work area.
     • Use hand signals agreed on before work starts.
   • Heat illness during long outdoor workMedium
     • Provide cool water, shade, and rest breaks; drink a cup about every 15–20 minutes in hot weather.
     • Watch your partner for confusion, cramps, or heavy sweating that stops.

7. 7. Cleanup: shut down and park equipment, clean tools, and secure the site.

   • Back and hand injuries lifting the compactorMedium
     • Use the machine lifting eye, a ramp, or two-person lift to load the compactor.
     • Wear work gloves when handling tools and rigging.
   • Public or workers falling into any remaining open excavationMedium
     • Barricade, cover, or fence any open hole before leaving the site.
     • Park equipment with buckets on the ground, keys removed, away from the edge.