UN 1922 — Pyrrolidine
Placard: Flammable. ERG Guide 132. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1922 is Pyrrolidine, a flammable corrosive amine assigned to ERG Guide 132. It can burn, flash back and cause chemical burns from liquid or vapor exposure.
Hazard overview: UN 1922 presents flammable vapor, corrosive amine, vapor explosion and alkaline runoff hazards. Water mixing may spread heat/fumes and corrosive contamination.
Response guidance: For a UN 1922 incident, responders should verify the product with shipping papers, package markings, SDS and ERG Guide 132. Establish incident command, isolate the area, stay upwind, control ignition or incompatibility hazards, prevent runoff or vapor spread and choose entry/fire-control actions based on monitoring, SDS and local SOP.
Firefighter training notes: Training for UN 1922 should emphasize vapor travel, flashback, sewer explosion, foam selection, container cooling, ignition control and toxic exposure where applicable. Use ERG 132, SDS and local SOP.
Regulatory context: Pyrrolidine is regulated as a hazardous material for transportation and emergency response purposes. Transportation, workplace exposure, spill reporting, waste handling, storage and environmental requirements may vary by formulation, concentration, quantity and jurisdiction. Verify current requirements through shipping papers, SDS, facility documents and applicable DOT, OSHA, EPA, NFPA, state or local authority guidance.
Storage & handling: Pyrrolidine should be stored in approved flammable/toxic-liquid containers with ventilation, bonding/grounding where required, spill containment and separation from heat, ignition sources, oxidizers and incompatible materials.
UN 1922 Quick Details
Common Hazards of UN 1922
- FLAMMABLE and CORROSIVE amine liquid; vapors may ignite and form explosive mixtures with air.
- Vapors are heavier than air and may travel to ignition sources and flash back.
- Liquid and vapor can burn eyes, skin and respiratory tissue.
- Soluble in water and may generate heat/fumes when mixed, spreading alkaline contamination.
- Vapor explosion hazard exists in sewers and confined spaces.
- Fire may produce nitrogen oxides and irritating/toxic smoke.
- Containers may rupture or explode when heated.
Chemical Identity & Physical Properties
Colorless to pale yellow liquid with a strong, ammonia-like or fishy odor. Hygroscopic and fumes in moist air.
| Also known as | TetrahydropyrroleAzacyclopentaneTetramethyleneiminePerhydropyrrole |
| CAS Number | 123-75-1 |
| Appearance | Colorless to pale yellow liquid with a strong, ammonia-like or fishy odor. Hygroscopic and fumes in moist air. |
| Flash Point | 3°C (37°F) |
| Boiling Point | 87°C (189°F) |
| Vapor Density | 2.45 (heavier than air) |
| Water Reactivity | Soluble in water; no significant violent reaction but releases heat and fumes |
Fireground Response Guidance — UN 1922
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 1922 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, fumes, dust, mist, smoke or gas and avoid skin or eye contact.
- Eliminate ignition sources if safe and keep vapors and runoff out of drains, sewers and low areas.
- Do not touch or walk through spilled 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 leak area and expand the perimeter if vapor, dust, fire involvement, gas accumulation or unknown concentration is present.
- Use ERG Guide 132, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 1922 — PyrrolidineUse 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.