UN 3529 — Machinery, internal combustion, flammable gas powered
Placard: Flammable Gas. ERG Guide 115. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3529 is Machinery, internal combustion, flammable gas powered, machinery with flammable gas fuel assigned to ERG Guide 115. Gas leaks, cylinder rupture and flashback are key hazards.
Hazard overview: Internal-combustion machinery containing flammable gas fuel; damaged cylinders, tanks or lines can release explosive gas. Propane/butane vapors may be heavier than air and collect in low areas; natural gas is lighter than air and may collect overhead. Gas may ignite easily and flash back to the leak source.
Response guidance: For UN 3529, isolate gas-fuel systems, eliminate ignition sources and cool cylinders from protection. Do not extinguish leak flames unless gas flow can be stopped.
Firefighter training notes: Training for UN 3529 should emphasize ignition control, fuel-system recognition, vapor/gas monitoring, cylinder or tank cooling, SCBA use and runoff control. Use ERG 115 and local SOP.
Regulatory context: Machinery, internal combustion, flammable gas powered is regulated as a hazardous material for transport and emergency response. Storage, reporting, exposure, waste and incident-notification duties depend on quantity, package type, gas identity and jurisdiction; verify shipping papers, SDS and authority guidance.
Storage & handling: Machinery, internal combustion, flammable gas powered should be stored away from ignition sources, heat and physical damage, with fuel/gas shutoffs secured and ventilation maintained where vapor or gas can accumulate.
UN 3529 Quick Details
Common Hazards of UN 3529
- Internal-combustion machinery containing flammable gas fuel; damaged cylinders, tanks or lines can release explosive gas.
- Propane/butane vapors may be heavier than air and collect in low areas; natural gas is lighter than air and may collect overhead.
- Gas may ignite easily and flash back to the leak source.
- Cylinders or fuel containers exposed to fire may vent, rupture or rocket.
- Equipment housings may hide leaking lines or residual pressure.
- Fire may involve plastics, oils and engine components.
- Exact fuel gas, cylinder/tank type and shutoff status must be verified.
Chemical Identity & Physical Properties
Machinery or equipment containing internal combustion engines powered by flammable gases such as propane, butane, or natural gas. Physical appearance varies widely depending on the type of equipment (forklifts, generators, vehicles). The hazard relates to the fuel system and residual flammable gas.
| Also known as | Flammable gas powered machineryInternal combustion engine equipmentGas-powered vehicles or equipmentLPG-powered machineryPropane-powered equipment |
| Appearance | Machinery or equipment containing internal combustion engines powered by flammable gases such as propane, butane, or natural gas. Physical appearance varies widely depending on the type of equipment (forklifts, generators, vehicles). The hazard relates to the fuel system and residual flammable gas. |
| Flash Point | Not applicable (machinery item containing flammable gas fuel) |
| Boiling Point | Not applicable (machinery item) |
| Vapor Density | Not applicable (machinery item; fuel gas typically heavier than air) |
| Water Reactivity | No significant reaction with water |
Fireground Response Guidance — UN 3529
Extinguishing Media
PPE Requirements
Use SCBA for fire, leaks or confined spaces plus flame-resistant protective clothing. Avoid ignition sources and gas accumulation areas.
Isolation & Evacuation
First Actions for a UN 3529 Incident
- Call 911 and the emergency response number on the shipping paper, if available.
- Keep unauthorized personnel away and establish incident command.
- Stay upwind, uphill and upstream.
- Eliminate ignition sources if this can be done safely.
- Avoid breathing vapor, gas, dust, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers, equipment, articles or spilled material without proper training and PPE.
- Prevent contaminated liquid, dust, runoff and decontamination waste from spreading.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 115, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 3529 — Machinery, internal combustion, flammablUse for: Quick radio or face-to-face size-up. Short, structured, field-ready.
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief.
Use for: Quick text to command or incoming units. Fits in a single SMS.