UN 2237 — Chloronitroanilines
Placard: Toxic. ERG Guide 153. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2237 is Chloronitroanilines, a toxic aromatic amine solid assigned to ERG Guide 153. Dust and skin absorption are major exposure concerns.
Hazard overview: HIGHLY TOXIC aromatic amine solid; may be harmful or fatal if inhaled, ingested or absorbed through skin. Skin absorption and contaminated dust are major response concerns. Combustible solid: may burn but does not ignite readily.
Response guidance: For a UN 2237 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 2237 should emphasize toxic skin/dust/vapor exposure, contaminated clothing, toxic fire products, decontamination waste and runoff containment. Use ERG 153, SDS and local SOP.
Regulatory context: Chloronitroanilines 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: Chloronitroanilines should be stored in tightly closed compatible containers in a secure toxic-material area with secondary containment, restricted access, ventilation and waste/decontamination planning according to SDS.
UN 2237 Quick Details
Common Hazards of UN 2237
- HIGHLY TOXIC aromatic amine solid; may be harmful or fatal if inhaled, ingested or absorbed through skin.
- Skin absorption and contaminated dust are major response concerns.
- Combustible solid: may burn but does not ignite readily.
- Molten material can cause severe burns to skin and eyes.
- Fire may produce hydrogen chloride, nitrogen oxides and other toxic gases.
- Runoff may carry toxic chlorinated aromatic amine contamination.
- Avoid dust generation and all skin contact.
Chemical Identity & Physical Properties
Yellow to orange crystalline solid or powder with a faint aromatic odor. Exists as various isomers (2-chloro-4-nitroaniline, 4-chloro-2-nitroaniline, etc.).
| Also known as | ChloronitroanilinesNitrochloroanilinesChloro-nitroanilinesCNA isomers |
| Appearance | Yellow to orange crystalline solid or powder with a faint aromatic odor. Exists as various isomers (2-chloro-4-nitroaniline, 4-chloro-2-nitroaniline, etc.). |
| Flash Point | Not applicable (combustible solid) |
| Boiling Point | Decomposes above 200C (392F) before boiling |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | No significant reaction with water; slightly soluble |
Fireground Response Guidance — UN 2237
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for dust, vapor, 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 2237 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 dust, liquid, 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 2237 — ChloronitroanilinesUse 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.