Flashing and Sheet Metal AHA (Activity Hazard Analysis / Job Hazard Analysis)
Updated 2026-06-23
A Flashing and Sheet Metal AHA (Activity Hazard Analysis / Job Hazard Analysis) is the plan that keeps the crew installing flashing and sheet metal safe from the at-height roof-edge and fall, from the sharp metal-edge cut and laceration, and around the fabrication tool and fastening. Flashing and sheet metal installs roof flashing and sheet-metal work — combining the at-height-roof-edge and fall hazard, the sharp-metal-edge-cut and laceration hazard, and the fabrication-tool and fastening hazard. This guide walks through building a Flashing and Sheet Metal AHA that names the at-height-roof-edge/fall, sharp-metal-edge-cut/laceration, and fabrication-tool/fastening hazards and assigns the fall, cut, and tool controls that hold up in the field.
Why flashing and sheet metal needs its own AHA
Flashing and sheet metal is the installation of roof flashing and sheet-metal work — the sheet-metal flashings (base flashing, counterflashing, cap flashing, valley flashing, and sheet-metal roof details) installed at roof edges, penetrations, walls, and transitions to weatherproof the roof. This heads the flashing/sheet-metal group. The defining feature is that flashing work concentrates at the roof edges and perimeter and at penetrations — the most exposed fall locations on the roof (the roof edge is exactly where flashing goes) — combined with the sharp edges of the cut sheet metal (a serious laceration hazard) and the fabrication tools and fastening. The hazards combine the at-height-roof-edge and fall (working at the roof edge and perimeter — the fall hazard), the sharp- metal-edge-cut and laceration (the sharp cut sheet-metal edges — the laceration hazard), the fabrication-tool and fastening (cutting, bending, and fastening the sheet metal — the tool and fastening hazards), and the eye. The at- height-roof-edge/fall and the sharp-metal-edge-cut/laceration justify a dedicated AHA.
Breaking flashing and sheet metal into steps
The steps for a Flashing and Sheet Metal AHA follow the work:
- Assess the roof edge/penetrations (fall exposure, access)
- Set up roof-edge fall protection (perimeter work)
- Measure, cut, and form the flashing (sharp edges, tools)
- Position and fasten the flashing (fastening)
- Seal the flashing (sealants)
- Manage the fall, cut, and tool hazards
- Complete
Each step carries a hazard, and the at-height-roof-edge/fall, the sharp-metal-edge-cut/laceration, and the fabrication-tool/fastening are where the most significant risks concentrate.
The hazards step by step
At-height-roof-edge and fall
Working at the roof edge and perimeter — the fall hazard. The controls are roof-edge fall protection (flashing work concentrates at the roof edges, perimeter, and penetrations — the most exposed fall locations on the roof, since edge/perimeter flashing is installed right at the fall line — so fall protection at the roof edge is especially critical (guardrails, personal fall arrest, warning-line systems as applicable), and safe access, recognizing that the worker's task literally puts them at the edge), and the fall controls. The at-height-roof-edge/fall is the primary defining hazard — flashing work is at the roof edge, the most exposed fall location. (These follow the roof-fall fundamentals.)
Sharp-metal-edge-cut and laceration
The sharp cut sheet-metal edges — the laceration hazard. The controls are sharp-metal-edge and laceration controls (cut and formed sheet-metal flashing has very sharp edges (freshly cut/sheared sheet metal edges are like blades — a serious laceration hazard, and handling long flashing pieces means the sharp edges can drag across hands/arms), so cut-resistant gloves and sleeves, careful handling, and deburring/hemming edges where practical), and the laceration controls. The sharp-metal-edge-cut/laceration is a defining hazard — cut sheet-metal edges cause serious lacerations. (These follow the sharp-edge fundamentals.)
Fabrication-tool and fastening
Cutting, bending, and fastening the sheet metal — the tool and fastening hazards. The controls are fabrication-tool and fastening controls (fabricating flashing involves cutting (snips, shears, and powered metal-cutting tools — the cut hazard), bending/forming (brakes and forming tools — pinch hazards), and fastening (fastening tools, and any soldering of metal flashing — the hot-soldering burn hazard), so safe tool use and fastening), and the tool/ fastening controls. The fabrication-tool/fastening is a defining hazard. (These follow the tool-safety fundamentals.)
Eye
The eye (metal cutting, swarf, fastening) carries the eye hazard. The controls are eye protection (metal cutting chips/swarf and fastening debris), and the eye controls. (These follow the eye-protection fundamentals.)
A simple Flashing and Sheet Metal AHA structure
| Step | Hazard | Control | Standard |
|---|---|---|---|
| Assess | Fall | Assess the roof edge/penetrations (fall exposure, access) | project |
| Fall protection | Fall | Set up roof-edge fall protection (perimeter work) | OSHA 1926.501 |
| Cut/form | Sharp edge / cut | Measure, cut, and form the flashing (sharp edges, tools) | project |
| Fasten | Fastening | Position and fasten the flashing (fastening) | OSHA 1926.302 |
| Seal | Chemical | Seal the flashing (sealants) | project |
| Manage | Fall / cut | Manage the fall, cut, and tool hazards | project |
Roof-edge fall protection and sharp-metal-edge/laceration control
A Flashing and Sheet Metal AHA centers on roof-edge fall protection and sharp-metal-edge/laceration control. The roof-edge fall protection addresses the perimeter work — controlled by roof-edge fall protection (fall protection at the edge, safe access). The sharp-metal-edge/laceration control addresses the cut metal edges — controlled by sharp-metal-edge and laceration controls (cut-resistant gloves and sleeves, careful handling, deburring). And the fabrication tools, fastening, and eye get tool/fastening and eye controls. An AHA built on roof-edge fall protection and sharp-metal-edge/laceration control, with tool/fastening controls, addresses the hazards that define flashing and sheet metal.
From the field: what actually goes wrong
In fourteen years across federal, heavy civil, and industrial projects, flashing and sheet metal installs the sheet-metal flashings (base, counter, cap, and valley flashing and sheet-metal roof details) that weatherproof the roof edges, penetrations, and transitions, and its defining hazards flow from where the work happens and what it is made of. The at-height-roof-edge and fall hazard is a primary defining concern — flashing work concentrates at the roof edges, perimeter, and penetrations, which are the most exposed fall locations on the roof, since edge and perimeter flashing is installed right at the fall line, so fall protection at the roof edge is especially critical (guardrails, personal fall arrest, warning-line systems as applicable) and the worker's task literally puts them at the edge — this is a case where the fall protection has to account for the work being done at the very location of the fall hazard. The roof-edge fall is the defining hazard.
The sharp-metal-edge-cut/laceration and the fabrication-tool/fastening are the other defining hazards. On the projects I have run, cut and formed sheet-metal flashing has very sharp edges — freshly cut or sheared sheet metal edges are like blades, a serious laceration hazard, and handling long flashing pieces means the sharp edges can drag across hands and arms — so cut-resistant gloves and sleeves, careful handling, and deburring or hemming edges where practical matter. And the fabrication-tool/fastening hazard is that fabricating flashing involves cutting (snips, shears, and powered metal-cutting tools), bending and forming (brakes and forming tools — pinch hazards), and fastening (fastening tools, and any soldering of metal flashing — the hot-soldering burn hazard). The eye hazard from metal cutting rounds it out. The AHA built on roof-edge fall protection and sharp-metal-edge/laceration control is the one that protects the flashing crew.
The bottom line
A Flashing and Sheet Metal AHA names the at-height-roof-edge/fall, the sharp-metal-edge-cut/laceration, and the fabrication-tool/fastening hazards with specific controls — roof-edge fall protection (fall protection at the edge where the work concentrates, safe access), sharp-metal-edge and laceration controls (cut-resistant gloves and sleeves, careful handling, deburring/hemming edges), and fabrication-tool and fastening controls (safe cutting, bending, fastening, and soldering). The roof-edge fall protection and the sharp-metal-edge/laceration control are the defining concerns. The AHA that manages both is the one that protects the crew.
Frequently asked questions
Why is the roof-edge fall the defining hazard?
Flashing work concentrates at the roof edges, perimeter, and penetrations, which are the most exposed fall locations on the roof — edge and perimeter flashing is installed right at the fall line, so the worker's task literally puts them at the edge. Controls are roof-edge fall protection (fall protection at the roof edge — guardrails, personal fall arrest, warning-line systems as applicable; safe access, recognizing the work is done at the fall location), and the fall controls.
Why are sharp metal edges a serious hazard?
Cut and formed sheet-metal flashing has very sharp edges — freshly cut/sheared sheet metal edges are like blades (a serious laceration hazard), and handling long flashing pieces means the sharp edges can drag across hands/arms. Controls are sharp-metal-edge and laceration controls (cut-resistant gloves and sleeves, careful handling, deburring/hemming edges where practical), and the laceration controls.
What fabrication-tool and fastening hazards apply?
Fabricating flashing involves cutting (snips, shears, powered metal-cutting tools), bending/forming (brakes and forming tools — pinch hazards), and fastening (fastening tools, and any soldering of metal flashing — the hot-soldering burn hazard). Controls are fabrication-tool and fastening controls (safe cutting, bending, fastening, and soldering), and the tool/fastening controls.
What is flashing and sheet metal?
Flashing and sheet metal is the installation of roof flashing and sheet-metal work — the sheet-metal flashings (base, counter, cap, and valley flashing and sheet-metal roof details) installed at roof edges, penetrations, walls, and transitions to weatherproof the roof. Because the work concentrates at the exposed roof edge (fall), the cut sheet-metal edges cause serious lacerations, and fabrication involves cutting/bending/fastening tools, those hazards apply.
Related AHAs and JHAs
- Sheet Metal Roofing AHA — the sheet-metal roofing
- Sheet Metal and Flashing Trim AHA — the sheet-metal and flashing trim
- Roof Specialties AHA — the related roof specialties
- Roof Flashing Installation JHA — the roof-flashing fundamentals
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.