UN 1664 — Nitrotoluenes, liquid
Placard: Toxic. ERG Guide 152. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1664 is Nitrotoluenes, liquid, a toxic nitroaromatic material assigned to ERG Guide 152. It may be solid or liquid, but skin absorption, toxic smoke and contaminated runoff are key responder concerns.
Hazard overview: UN 1664 presents toxic skin, inhalation and ingestion hazards. It may burn or decompose under fire conditions, producing toxic nitrogen oxide smoke; molten or liquid material can also injure skin.
Response guidance: For a UN 1664 incident, responders should verify the product with shipping papers, package markings, SDS and ERG Guide 152. Establish incident command, isolate the area, stay upwind, prevent dust or vapor exposure, control runoff and choose entry or cleanup actions based on monitoring, SDS and local SOP.
Firefighter training notes: Training for UN 1664 should emphasize nitroaromatic toxicity, skin absorption, molten/liquid exposure, toxic smoke and runoff containment. Use ERG 152, SDS and local SOP.
Regulatory context: Nitrotoluenes, liquid 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: Nitrotoluenes, liquid should be stored in tightly closed compatible containers in a secure, cool, dry, well-ventilated toxic-material area away from heat, ignition sources, oxidizers, acids/bases where incompatible and unauthorized access. Prevent dust release, skin contact and contaminated runoff.
UN 1664 Quick Details
Common Hazards of UN 1664
- TOXIC nitroaromatic material; inhalation, ingestion or skin absorption may cause severe injury.
- Combustible material: may burn but does not ignite readily.
- Liquid or molten material can cause thermal injury and toxic skin absorption.
- Heating or fire may produce toxic nitrogen oxides and irritating smoke.
- Runoff may carry toxic contamination to drains or waterways.
- Containers may rupture or fail when heated.
- Avoid skin contact because absorption may be significant for some nitroaromatic compounds.
Chemical Identity & Physical Properties
Pale yellow to brown oily liquid with a weak aromatic odor. Exists as ortho-, meta-, and para-isomers or mixtures thereof at room temperature.
| Also known as | MononitrotolueneMNTNitrotoluolMethylnitrobenzeneToluene mononitrate |
| Appearance | Pale yellow to brown oily liquid with a weak aromatic odor. Exists as ortho-, meta-, and para-isomers or mixtures thereof at room temperature. |
| Flash Point | 106-112C (223-234F) depending on isomer |
| Boiling Point | 222-238C (432-460F) depending on isomer |
| Vapor Density | 4.7 (heavier than air) |
| Water Reactivity | No significant reaction with water; very slightly soluble |
Fireground Response Guidance — UN 1664
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for vapor, dust, fire or confined-space exposure. Chemical-resistant gloves, eye/face protection and protective clothing should be selected from SDS because skin absorption may be significant.
Isolation & Evacuation
First Actions for a UN 1664 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 or mist and avoid all skin or eye contact.
- Keep vapors and runoff out of drains, sewers and low areas where practical.
- Do not touch or walk through spilled material unless properly trained and wearing appropriate protective equipment.
- Avoid creating dust clouds or spreading contaminated liquid, powder, solution, runoff or debris.
- 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 dust, vapor, fire involvement or unknown concentration is present.
- Use ERG Guide 152, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 1664 — Nitrotoluenes, liquidUse 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.