First, describe the work and worksite
A roofing crew forms a reinforced two-component liquid flashing around one accepted metal roof penetration on a compatible existing single-ply membrane. The selected JM system requires substrate-specific preparation and primer, dry-fitted scrim, controlled mixing and cure. No penetration opening or equipment support is cut or altered. This fictional learning example describes planned controls; it records no actual inspection or work authorization.
- Partial flashing coverage: a compatible liquid resin and reinforcing scrim detail; no sheet-membrane hot-air welding, penetration creation or structural equipment work.
- The actual membrane, metal surface, system detail and adhesion requirements are approved; active services and the penetration remain protected.
- The crew has current product instructions and SDS, accepted roof access and fall controls, ventilation and weather conditions suitable for application and cure.
Questions before work
- Which preparation and primer apply to the membrane and metal surfaces, and who resolves doubtful adhesion?
- How will packaged components, mixing and working time be controlled under actual temperature conditions?
- What keeps the reinforced detail dry, undisturbed and restricted until its cure and inspection requirements are met?
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. Accept compatibility and application conditions
Hazard: An incompatible substrate or damp surface can produce a failed bond beneath a finished-looking detail.
Control: Identify the existing membrane and penetration and accept the system detail with the responsible people. Check weather, surface dryness, temperature and dew-point criteria from current instructions; resolve doubtful adhesion before preparation.
Verification: Roof lead records the approved materials, detail and actual application conditions.
Why this belongs in the analysis: A liquid that sticks briefly may still lack the required long-term compatibility and bond.
2. Prepare the accepted flashing surfaces
Hazard: Abrasion, solvents and loose coatings can injure workers or damage adjacent membrane.
Control: Mask the approved area and perform substrate-specific preparation with assessed dust and tool controls. Use the required cleaners with SDS-based ventilation and protection, control ignition sources and leave accepted surfaces clean and dry without enlarging the repair.
Verification: Installer checks prepared metal and membrane against the actual system criteria before priming.
Why this belongs in the analysis: Metal and membrane require different preparation; a generic wipe does not accept both.
3. Dry fit reinforcement and prime each substrate
Hazard: Unplanned fabric cuts or an incorrect primer can leave voids or expose workers to chemicals.
Control: Precut and dry-fit the specified clean scrim to the accepted detail and overlaps. Remove it to protected storage, apply each substrate’s compatible primer and verify its prescribed flash-off or cure before resin application.
Verification: Lead records scrim fit, primer identity and surface readiness for the selected system.
Why this belongs in the analysis: Preparing reinforcement first reduces rushed cutting during the resin’s limited working period.
4. Mix the identified resin components
Hazard: Incorrect component mixing or an expired working period can cause poor cure and chemical exposure.
Control: Use the actual packaged-component procedure, compatible mixing equipment and SDS controls. Record the mix start and applicable working time, prevent contamination and unauthorized dilution, and reject material that exceeds its usable conditions.
Verification: Installer confirms component identity, uniform mix and the working-time record before application.
Why this belongs in the analysis: Resin appearance alone does not establish correct proportion, mixing or remaining working time.
5. Embed and cover the reinforcement
Hazard: Dry fabric, wrinkles and trapped voids can interrupt the waterproof detail.
Control: Apply the specified resin, seat the pre-fitted scrim and fully embed and cover it according to the detail. Maintain the required coverage and transitions, avoid air pockets and protect the wet work from traffic, rain and contamination.
Verification: Lead checks saturated reinforcement, overlaps, coverage and the controlled cure area.
Why this belongs in the analysis: The reinforcement must form part of a continuous resin detail rather than sit dry beneath a top coat.
6. Accept cure and release the detail
Hazard: Premature use or hidden discontinuities can damage the flashing and expose the next crew.
Control: Maintain protection through the actual cure conditions and inspect the completed detail by the system requirements. Record defects and repairs, collect chemical waste as directed and release the area only after the required inspection and cure are accepted.
Verification: Roof lead records the cure disposition, detail acceptance and any remaining restriction.
Why this belongs in the analysis: Dry-to-touch material does not automatically meet all requirements for traffic or weather exposure.
What does a useful control look like?
| Needs improvement | More useful for this scenario |
|---|---|
| Work carefully and wear PPE. | Precut and dry-fit the specified clean scrim to the accepted detail and overlaps. Remove it to protected storage, apply each substrate’s compatible primer and verify its prescribed flash-off or cure before resin application. |
| Check that everything is ready. | Identify the existing membrane and penetration and accept the system detail with the responsible people. Check weather, surface dryness, temperature and dew-point criteria from current instructions; resolve doubtful adhesion before preparation. |
Decisions that change the analysis
Why is this separate from welded TPO curb flashing?
This develops substrate-specific priming, packaged liquid mixing, embedded scrim and controlled chemical cure. The welded sheet detail forms its junction by hot-air fusion and does not establish these liquid-system controls.
What must the crew record for actual use?
Identify the actual equipment and work boundaries, responsible people, applicable criteria, inspection findings and open actions. Resolve changes with affected crews and obtain required project authorization before work.
Agree when the crew will pause
- Pause for unverified compatibility, poor adhesion, wet surfaces or conditions outside the actual system limits.
- Stop for inadequate ventilation, wrong primer, expired mixed material or incomplete reinforcement.
- Opening a new penetration or altering its supporting equipment requires a separate work scope.
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
- Demonstrate the specified system’s preparation, primer selection, reinforcement fit, mixing and cure acceptance.
- Verify instruction on actual SDS exposure controls, tools, chemical waste and protected roof work positions.
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 format and actual conditions. The example is a teaching aid, not evidence that controls were checked.
What changes if the project requires an AHA?
Use the governing AHA format, risk method, supporting records and acceptance process. The published formwork AHA demonstrates that additional structure; changing a JHA title does not supply it.
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
- JM Single Ply Liquid Flashing installation guide RS-7123
- OSHA 1910.1200 Hazard communication
- OSHA 1926.300 Hand and power tools
- OSHA 1926.501 Duty to have fall protection
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.