UN 2300 — 2-Methyl-5-ethylpyridine
Placard: Toxic. ERG Guide 153. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2300 is 2-Methyl-5-ethylpyridine, a toxic/corrosive amine-type liquid assigned to ERG Guide 153. It can cause chemical burns, systemic exposure and contaminated runoff.
Hazard overview: TOXIC and CORROSIVE amine liquid; inhalation, ingestion or skin contact may cause severe injury. Liquid and vapor can burn eyes, skin and respiratory tissue. Combustible material: may burn but does not ignite readily.
Response guidance: For a UN 2300 incident, verify the product with shipping papers, container markings, SDS and ERG Guide 153. Establish incident command, isolate the area, stay upwind, control ignition or incompatibility hazards, prevent runoff, dust or vapor spread and base entry/fire-control actions on monitoring and local SOP.
Firefighter training notes: Training for UN 2300 should emphasize toxic skin/vapor/dust exposure, contaminated clothing, toxic fire products, decontamination waste and runoff containment. Use ERG 153, SDS and local SOP.
Regulatory context: 2-Methyl-5-ethylpyridine 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: 2-Methyl-5-ethylpyridine should be stored in tightly closed compatible containers in a secure toxic/corrosive-material area with secondary containment, restricted access, ventilation and segregation from acids, oxidizers and incompatible chemicals.
UN 2300 Quick Details
Common Hazards of UN 2300
- TOXIC and CORROSIVE amine liquid; inhalation, ingestion or skin contact may cause severe injury.
- Liquid and vapor can burn eyes, skin and respiratory tissue.
- Combustible material: may burn but does not ignite readily.
- Vapors may be heavier than air and collect in low or confined areas when heated.
- Fire may produce nitrogen oxides and irritating/toxic smoke.
- Runoff may be alkaline, toxic, corrosive and environmentally harmful.
- Containers may rupture or fail when heated.
Chemical Identity & Physical Properties
Colorless to pale yellow liquid with a characteristic pyridine-like or amine odor. Liquid at room temperature.
| Also known as | 5-Ethyl-2-methylpyridine2-Methyl-5-ethyl pyridineMEPAldehyde collidine |
| CAS Number | 104-90-5 |
| Appearance | Colorless to pale yellow liquid with a characteristic pyridine-like or amine odor. Liquid at room temperature. |
| Flash Point | 78°C (172°F) |
| Boiling Point | 178-179°C (352-354°F) |
| Vapor Density | 4.2 (heavier than air) |
| Water Reactivity | No significant reaction with water, though slightly soluble |
Fireground Response Guidance — UN 2300
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for vapor, dust, mist, fire or confined-space exposure. Wear chemical-resistant gloves, boots, eye/face protection and protective clothing selected from SDS; avoid all skin contact.
Isolation & Evacuation
First Actions for a UN 2300 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, dust, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers or spilled material unless properly trained and wearing appropriate protective equipment.
- Prevent contaminated liquid, dust, residues, runoff and decontamination waste from spreading.
- 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, dust generation, water reaction or unknown product identity.
- Use ERG Guide 153, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 2300 — 2-Methyl-5-ethylpyridineUse 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.