UN 2058 — Valeraldehyde
Placard: Flammable. ERG Guide 129. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2058 is Valeraldehyde, a Class 3 flammable liquid assigned to ERG Guide 129. Vapors can travel to ignition sources and flash back, especially in drains or confined spaces.
Hazard overview: FLAMMABLE liquid; vapors may ignite and form explosive mixtures with air. Vapors are heavier than air and may travel to ignition sources and flash back. Vapor explosion hazard exists in low areas, drains, sewers and confined spaces.
Response guidance: For a UN 2058 incident, verify the product with shipping papers, container markings, SDS and ERG Guide 129. Establish incident command, isolate the area, stay upwind, control ignition or incompatibility hazards, prevent runoff or vapor spread and base entry/fire-control actions on monitoring and local SOP.
Firefighter training notes: Training for UN 2058 should emphasize exposure routes, air monitoring, PPE selection, fire behavior, decontamination, runoff containment and ERG/SDS verification. Use ERG 129, SDS and local SOP.
Regulatory context: Valeraldehyde is regulated as a hazardous material for transportation and emergency response purposes. Storage, workplace exposure, emergency planning, spill reporting, waste handling and environmental requirements vary by exact product, concentration, quantity and jurisdiction. Verify current requirements through shipping papers, SDS, container markings and applicable DOT, OSHA, EPA, NFPA, state or local authority guidance.
Storage & handling: Valeraldehyde should be stored in approved flammable-liquid containers with ventilation, bonding/grounding where required, spill containment and separation from heat, ignition sources, oxidizers and incompatible materials.
UN 2058 Quick Details
Common Hazards of UN 2058
- FLAMMABLE liquid; vapors may ignite and form explosive mixtures with air.
- Vapors are heavier than air and may travel to ignition sources and flash back.
- Vapor explosion hazard exists in low areas, drains, sewers and confined spaces.
- Runoff to sewers may create fire or explosion hazards.
- Containers may rupture or explode when heated.
- Fire may produce irritating and/or toxic smoke.
- Specific solvent or hydrocarbon exposure hazards should be confirmed from SDS.
Chemical Identity & Physical Properties
Colorless to pale yellow liquid with a pungent, disagreeable odor. Less dense than water and only slightly soluble in water.
| Also known as | PentanalValeric aldehyden-ValeraldehydeAmyl aldehyden-Pentanal |
| CAS Number | 110-62-3 |
| Appearance | Colorless to pale yellow liquid with a pungent, disagreeable odor. Less dense than water and only slightly soluble in water. |
| Flash Point | -1C (30F) |
| Boiling Point | 103C (217F) |
| Vapor Density | 3.0 (heavier than air) |
| Water Reactivity | No significant reaction; slightly soluble in water |
Fireground Response Guidance — UN 2058
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for vapor, fire or confined-space exposure. Wear chemical-resistant gloves, eye/face protection, flame-resistant protection as appropriate and PPE selected from SDS.
Isolation & Evacuation
First Actions for a UN 2058 Incident
- CALL 911. Then call the emergency response telephone number on the shipping paper, if available.
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Avoid breathing vapors, gas, dust, mist, smoke or fumes and avoid skin or eye contact.
- Eliminate ignition sources if safe and keep vapors and runoff out of drains, sewers, basements and low areas.
- Do not touch damaged containers or spilled/released material unless properly trained and wearing appropriate protective equipment.
- Ventilate closed spaces before entering, but only if properly trained, equipped, monitored and authorized by incident command.
- Isolate the spill or release area and expand the perimeter for fire involvement, vapor spread, gas accumulation, cylinder heating or unknown product identity.
- Use ERG Guide 129, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 2058 — ValeraldehydeUse 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.