Structural Welding AHA (Activity Hazard Analysis / Job Hazard Analysis)
Updated 2026-06-23
A Structural Welding AHA (Activity Hazard Analysis / Job Hazard Analysis) is the plan that keeps the crew doing structural welding safe from the arc radiation and electric shock, from the welding fume and respiratory hazard, and around the fire, hot work, and at-height welding. Structural welding welds structural steel connections and members — combining the arc-radiation and electric-shock hazard, the welding-fume and respiratory hazard, and the fire, hot-work, and at-height hazard. This guide walks through building a Structural Welding AHA that names the arc-radiation/electric-shock, welding-fume/respiratory, and fire-hot-work/at-height hazards and assigns the arc, fume, and fire controls that hold up in the field.
Why structural welding needs its own AHA
Structural welding is the welding of structural steel — welding the connections, joints, and members of the steel frame (beam-to-column connections, splices, moment connections, and structural attachments), typically with arc welding processes (stick/SMAW, flux-cored/FCAW, and others). This opens the metals division (Division 05). The defining feature is the arc welding on the structure: the welding arc (intense radiation and electric shock), the welding fume (metal fume — a respiratory hazard), and the fire/hot-work hazard (welding is hot work with sparks and molten metal), all often performed at height on the steel structure. The hazards combine the arc-radiation and electric-shock (the welding arc — the radiation hazard (the intense arc emits UV/IR radiation — "arc eye"/ burns) and the electric-shock hazard (the welding current/equipment)), the welding-fume and respiratory (the welding fume — the respiratory hazard (metal fume from welding — including manganese and other metals, and fume from any coatings)), the fire, hot-work, and at-height (welding is hot work (sparks, molten metal, fire hazard) often performed at height on the structure — the fire and fall hazards), and the burn/equipment. The arc-radiation/electric-shock and the fire-hot-work/at-height justify a dedicated AHA.
Breaking structural welding into steps
The steps for a Structural Welding AHA follow the welding:
- Set up the welding equipment and verify the electrical/ground
- Set up the hot-work area (fire watch, clear combustibles)
- Set up ventilation/fume control
- Establish the at-height welding position (fall protection)
- Weld the structural connection (arc/shock/fume controls)
- Manage the arc, fume, and fire hazards
- Post-weld: fire watch, inspect
- Complete
Each step carries a hazard, and the arc-radiation/electric-shock, the welding-fume/respiratory, and the fire-hot-work/at-height are where the most significant risks concentrate.
The hazards step by step
Arc-radiation and electric-shock
The welding arc — the radiation hazard (the intense arc emits UV/IR radiation — "arc eye"/burns) and the electric-shock hazard (the welding current/equipment). The controls are arc-radiation protection (welding helmet with the correct shade, protecting the eyes and skin from the arc's UV/IR — arc flash causes "arc eye" and skin burns, and screening the arc to protect nearby workers), electric-shock protection (the welding circuit and equipment — proper grounding, insulated/dry conditions, good cable/holder condition, not welding in wet conditions or on a wet structure without precautions, and the higher shock risk in confined/damp positions), and the arc/shock controls. The arc-radiation/electric-shock is a defining hazard — the arc burns and the welding current can shock. (These follow the arc-welding fundamentals.)
Welding-fume and respiratory
The welding fume — the respiratory hazard (metal fume from welding — including manganese and other metals, and fume from any coatings). The controls are welding-fume control (ventilation, local exhaust, or respiratory protection for the welding fume — welding fume contains metal oxides including manganese, a neurotoxin, and fume from coatings (galvanizing/zinc — metal fume fever; lead or other coatings) can be more hazardous, so identifying coatings and controlling the fume), and the fume/respiratory controls. The welding-fume/respiratory is a defining hazard — welding fume is a respiratory hazard. (These follow the welding-fume fundamentals.)
Fire, hot-work, and at-height
Welding is hot work (sparks, molten metal, fire hazard) often performed at height on the structure — the fire and fall hazards. The controls are the hot-work program (fire watch, fire extinguisher, clearing/protecting combustibles below and around — welding throws sparks and molten metal that fall and start fires, especially from height, a hot-work permit and fire watch), fall protection for at-height welding (welding on the steel structure at height — fall protection), and the fire/at-height controls. The fire-hot-work/at-height is a defining hazard — welding is hot work at height. (These follow the hot-work and fall-protection fundamentals.)
Burn/equipment
The burn and equipment (hot metal, welding equipment) carries the burn/equipment hazard. The controls are burn protection (hot metal, slag — PPE), safe equipment operation, and the burn/equipment controls. (These follow the burn-protection fundamentals.)
A simple Structural Welding AHA structure
| Step | Hazard | Control | Standard |
|---|---|---|---|
| Set up equipment | Shock | Set up welding equipment, verify electrical/ground | project |
| Hot-work area | Fire | Set up hot-work area (fire watch, clear combustibles) | OSHA 1926.352 |
| Ventilation | Fume | Set up ventilation/fume control | OSHA 1926.353 |
| Position | Fall | Establish at-height welding position (fall protection) | OSHA 1926.501 |
| Weld | Arc / shock / fume | Weld the connection (arc/shock/fume controls) | OSHA 1926.351 |
| Post-weld | Fire | Fire watch, inspect | OSHA 1926.352 |
Arc/shock protection and fume/fire-hot-work control
A Structural Welding AHA centers on arc/shock protection and fume/fire-hot-work control. The arc/shock protection addresses the welding arc — controlled by arc-radiation protection (welding helmet with correct shade, screening the arc) and electric-shock protection (grounding, dry conditions, good cable condition). The fume/fire-hot-work control addresses the fume and the fire — controlled by welding-fume control (ventilation, local exhaust, or respiratory protection, identifying hazardous coatings) and the hot-work program (fire watch, clearing combustibles), plus fall protection for at-height welding. And the burns and equipment get burn and equipment controls. An AHA built on arc/shock protection and fume/fire-hot-work control, with fall protection, addresses the hazards that define structural welding.
From the field: what actually goes wrong
In fourteen years across federal, heavy civil, and industrial projects, structural welding welds the connections and members of the steel frame, and it opens the metals division. Its defining hazards are the classic welding hazards — the arc, the fume, and the fire — intensified by the structural context (at height, on the frame). The arc-radiation and electric-shock hazard is a primary defining concern — the welding arc is intensely bright and emits ultraviolet and infrared radiation that causes "arc eye" (painful photokeratitis, like a sunburn on the eye) and skin burns, so arc-radiation protection (a welding helmet with the correct shade lens, protecting the eyes and skin, and screening the arc to protect nearby workers from flash) is essential, and the welding current and equipment are an electric-shock hazard, controlled by proper grounding, dry conditions and equipment, good cable and electrode-holder condition, and extra care in wet or confined damp positions where shock risk rises. The arc's radiation and the electric shock are the ever-present welding hazards.
The welding-fume/respiratory and the fire-hot-work/at-height are the other defining hazards. On the projects I have run, welding fume is a real respiratory hazard — welding generates metal fume (metal oxides including manganese, which is a neurotoxin of increasing concern), and fume from coatings can be worse (welding on galvanized steel releases zinc fume causing metal fume fever, and welding on lead-painted or other coated steel releases those hazards), so identifying coatings and controlling the fume with ventilation, local exhaust, or respiratory protection is a control. And the fire-hot-work/at-height hazard is central to structural welding: welding is hot work that throws sparks and molten metal, which fall — especially from height on the structure — and start fires below, so the hot-work program (fire watch, fire extinguisher, clearing and protecting combustibles below and around, hot-work permit) is essential, along with fall protection for welding at height on the steel. Sparks and molten metal falling from height welding is a serious fire-ignition hazard. The burns from hot metal and slag round it out. The AHA built on arc/shock protection and fume/fire-hot-work control is the one that protects the welding crew.
The bottom line
A Structural Welding AHA names the arc-radiation/electric-shock, the welding-fume/respiratory, and the fire-hot- work/at-height hazards with specific controls — arc-radiation protection (helmet, correct shade, arc screening) and electric-shock protection, welding-fume control (ventilation/exhaust/respiratory, identifying hazardous coatings), and the hot-work program (fire watch, clearing combustibles) with fall protection for at-height welding. The arc/shock protection and the fume/fire-hot-work control are the defining concerns. The AHA that manages both is the one that protects the crew.
Frequently asked questions
What arc and shock hazards apply to structural welding?
The welding arc is intensely bright and emits ultraviolet and infrared radiation causing "arc eye" (painful photokeratitis) and skin burns, and the welding current and equipment are an electric-shock hazard. Controls are arc-radiation protection (welding helmet with correct shade, protecting eyes and skin, screening the arc to protect nearby workers), electric-shock protection (proper grounding, dry conditions and equipment, good cable/holder condition, extra care in wet/confined positions), and the arc/shock controls.
Why is welding fume a respiratory hazard?
Welding generates metal fume (metal oxides including manganese, a neurotoxin of increasing concern), and fume from coatings can be worse — welding on galvanized steel releases zinc fume causing metal fume fever, and welding on lead-painted or coated steel releases those hazards. Controls are welding-fume control (ventilation, local exhaust, or respiratory protection, identifying coatings and controlling the fume), and the fume/respiratory controls.
Why is fire/hot-work central to structural welding?
Welding is hot work that throws sparks and molten metal, which fall — especially from height on the structure — and start fires below. Controls are the hot-work program (fire watch, fire extinguisher, clearing/protecting combustibles below and around, hot-work permit), fall protection for at-height welding, and the fire/at-height controls.
What is structural welding?
Structural welding is the welding of structural steel — welding the connections, joints, and members of the steel frame (beam-to-column connections, splices, moment connections, structural attachments), typically with arc welding processes. Because the arc causes radiation and shock, welding fume is a respiratory hazard, and welding is hot work often done at height, those hazards apply.
Related AHAs and JHAs
- Structural Steel Framing AHA — the steel framing that is welded
- Structural Metal Framing AHA — the metal framing fundamentals
- Welding Operations JHA — the welding fundamentals
- Hot Work JHA — the hot-work 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.