First, describe the work and worksite
A trained operator will use an engine-powered, hand-guided vibrating wet screed on one outdoor ground-level slab bay. Concrete is already distributed within the agreed boundary. The actual drive/profile and engine manuals govern operation. Work ends with safe shutdown, cleaning and handover before later finishing and curing. This fictional learning example describes planned controls; it records no actual inspection or work authorization.
- The slab bay has established level-control references and stable operator routes. The responsible finishing lead accepts the concrete condition for this machine operation; workers do not improvise supports, profiles or vibration settings to compensate for an unsuitable bay.
- The actual drive unit, profile combination and engine manuals establish assembly, lifting, starting, operating, stopping, adjustment and fueling requirements. The employer evaluates noise, vibration, wet-cement contact and combustion-exhaust exposure for the work.
- This is partial coverage of placement and finishing activity 238110-09, limited to powered wet-screed operation. Pump placement, manual straightedge or bull-floating, powered troweling, enclosed combustion-engine use and curing application are separate scopes.
Questions before work
- Which compatible drive and blade combination, manual and concrete conditions are accepted for this bay?
- How will the operator maintain a stable route and keep nearby workers clear of the moving blade and hot engine?
- Where can adjustment, cleaning and refueling take place after the required stop, isolation and cooling?
Build the analysis one step at a time
What will the worker do? How could someone be harmed? What prevents or reduces that exposure? Who checks the control, and when?
1. Confirm the bay and machine method
Hazard: Unsuitable concrete, unclear level references or unstable footing can cause loss of control and repeated strenuous passes.
Control: Finishing lead identifies the accepted bay, references and planned pass arrangement. Confirm the concrete condition and selected machine/profile combination with the actual instructions. Establish clear operator routes and coordination with the distribution crew; resolve incompatible conditions before placing the screed into service.
Verification: Lead and operator check the bay boundaries, references, footing and equipment identity together.
Why this belongs in the analysis: Machine readiness includes a workable slab sequence, not merely an engine that starts.
2. Assemble and examine the screed
Hazard: An insecure profile or defective control can release a component or expose the operator to moving parts.
Control: With the unit stopped and isolated as instructed, the trained operator fits the compatible profile and confirms attachment, guards, handles and controls using the actual manual. Arrange any required handling assistance. Remove damaged or incompatible components from use rather than adding improvised fasteners or supports.
Verification: Operator records the pre-use findings and confirms secure assembly with the finishing lead.
Why this belongs in the analysis: Profile length and attachment affect handling; a generic substitute can change the planned operation.
3. Prepare the operator and controlled start
Hazard: An unexpected start, hot exhaust or people beside the blade can cause contact injuries or hazardous exposure.
Control: Establish the start position and clear the blade area. Use the employer’s eye, skin, noise and other assessed protection, with access to prompt cement-contact washing. Keep engine exhaust away from people and air intakes; follow the model’s start procedure and verify its stop control before production work.
Verification: Operator verifies the boundary, exhaust direction and required control-function checks before a pass.
Why this belongs in the analysis: Outdoor work still requires attention to where exhaust and other workers are located.
4. Make controlled vibrating screed passes
Hazard: A moving profile, awkward pulling position or prolonged vibration can injure workers or cause the operator to lose footing.
Control: Operator uses the actual instructions and accepted bay method to control the profile and vibration. Maintain stable footing, safe hand positions and clear separation from helpers. Coordinate any repositioning rather than having someone grab the operating blade; stop when concrete condition, footing or fatigue prevents controlled work.
Verification: Finishing lead observes initial handling and checks that the operator route and separation remain effective.
Why this belongs in the analysis: A consistent pass depends on controlled movement rather than extra force or more vibration.
5. Stop before repositioning or adjustment
Hazard: Adjusting the drive or profile while it can move can trap hands, burn skin or restart unexpectedly.
Control: Follow the actual stopping and isolation procedure before changing attachments, vibration arrangements or operating positions. Allow hot parts to cool as required. Use the instructed handling method and assistance for relocation; keep adjustments within the selected manual and refer defects for authorized correction before restart.
Verification: Operator verifies stopped movement and the prescribed isolated condition before anyone touches adjustment points.
Why this belongs in the analysis: The control setting used in production is not protection against an unintended restart.
6. Clean, refuel and hand over safely
Hazard: Contact with hot equipment, spilled fuel or hardened residue can create fire, handling or next-use hazards.
Control: After shutdown and cooling, clean the unit using its instructions and the site’s residue containment method. Refuel only in the prescribed safe condition away from ignition and the wet work boundary. Record defects and hand over the struck-off bay for its separately planned next finishing and curing steps.
Verification: Operator checks storage condition and reports equipment defects; lead confirms the next crew’s bay boundary.
Why this belongs in the analysis: A clean-looking slab does not establish that the machine or subsequent finishing operation is ready.
What does a useful control look like?
| Needs improvement | More useful for this scenario |
|---|---|
| Pull harder and turn up the vibration. | Stop and resolve concrete condition, pass method and machine compatibility with the lead using the selected unit’s instructions. |
| Have a helper hold the blade while it runs. | Use planned crew separation and stop/isolate before any handling or adjustment that enters the blade or drive danger area. |
Decisions that change the analysis
Does the manual screeding and bull-floating resource cover this machine?
No. Manual tools use a different handling and finishing sequence. This powered unit combines strike-off with machine vibration and introduces drive controls, engine exhaust, fuel, moving components and model-specific isolation. It also precedes the separate rotary power-trowel finishing operation.
What must the crew record for actual use?
Record the bay and accepted concrete condition, level references, unit and profile identity, manual revision, actual assembly and pre-use findings, operator assignment, exposure controls and work boundary. Record stop or adjustment decisions, equipment defects and the next-operation handover. Do not copy a universal speed, vibration force or exposure-duration limit into the record.
Agree when the crew will pause
- The blade attachment, guard, handle, stop control or engine condition does not meet the actual pre-use requirements.
- Footing, concrete condition, nearby workers, exhaust direction or fatigue prevents the planned controlled passes.
- An adjustment, blockage, fuel leak or damaged component requires intervention beyond the operator’s authorized stopped-work procedure.
After a pause, correct the condition, reassess the work, and obtain required authorization before restarting. Keep unresolved actions visible.
Download the worked example and free template
No account required. The worked example contains planned controls. The blank template is for your own work; neither includes fabricated inspection results, signatures or approval.
Your editable working copy
Build and download your draft
Start blank or load the learning example. Replace its assumptions with your actual conditions and involve the people doing the work. Your entries stay in this browser tab; download a copy before leaving or refreshing.
1. Describe your work and site
2. Work through each task
Describe an observable step, how someone could be harmed, and the control that acts on that hazard. Identify who checks it and what evidence is needed.
3. Record changes, checks, and open actions
Walk the work area, review with the crew, and resolve missing controls. Follow the required approval process. This tool does not judge completeness, verify signatures or authorize work.
Open the downloaded file in a browser, then use Print → Save as PDF for a printable copy.
Training needs to confirm
- Selected-machine instruction on profile compatibility, attachments, controls, passes and verified isolation before adjustment; demonstrate hands-clear operation.
- Instruction on exhaust, fuel, wet-cement contact and noise/vibration controls; recognize fatigue or exposure conditions that require the employer’s response.
Confirm applicable qualifications, task instruction and actual training evidence for the people assigned. Related toolbox talks support toolbox talks; they do not establish competence.
Common questions
Can this example be used as a JSA?
Adapt its Task | Hazard | Control analysis to the employer’s JSA format and actual work. Confirm assigned checks and record real findings before relying on the plan.
What changes if the project requires an AHA?
Use the project’s governing AHA format, risk method, supporting records and acceptance process. The published formwork AHA illustrates that additional structure; this JHA establishes no AHA risk rating or acceptance.
Are these resources part of a paid course?
This walkthrough, browser draft builder and downloads are free public resources, separate from Academy course enrollment.
References and source note
- Wacker Neuson P35A hand-guided vibrating screed overview
- OSHA 1926.300 Powered-tool condition and guarding
- OSHA 1926.55 Gases, vapors, fumes, dusts and mists
Original instructional scenario with planned controls. Primary references support hazard planning. Use actual equipment and product instructions, project design and employer requirements to establish field criteria. This example supplies no inspection findings or work authorization. Use actual equipment instructions and site requirements alongside these references. Reference review: October 9, 2026.