UN 2021 — Chlorophenols, liquid
Placard: Toxic. ERG Guide 153. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2021 is Chlorophenols, liquid, a toxic/corrosive chlorophenol entry assigned to ERG Guide 153. Skin absorption, phenolic toxicity and contaminated runoff require careful control.
Hazard overview: TOXIC and CORROSIVE chlorophenol material; inhalation, ingestion or skin contact may cause severe injury. Skin absorption and contaminated clothing can extend exposure. Combustible material: may burn but does not ignite readily.
Response guidance: For a UN 2021 incident, verify the product with shipping papers, container markings, SDS and ERG Guide 153. Establish incident command, isolate the area, stay upwind, prevent incompatible contact, control runoff or dust spread and base entry/fire-control actions on monitoring and local SOP.
Firefighter training notes: Training for UN 2021 should emphasize toxic exposure routes, skin absorption, air monitoring, PPE selection, decontamination, runoff containment and ERG/SDS verification. Use ERG 153, SDS and local SOP.
Regulatory context: Chlorophenols, liquid 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: Chlorophenols, liquid 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 2021 Quick Details
Common Hazards of UN 2021
- TOXIC and CORROSIVE chlorophenol material; inhalation, ingestion or skin contact may cause severe injury.
- Skin absorption and contaminated clothing can extend exposure.
- Combustible material: may burn but does not ignite readily.
- Molten material can cause severe burns to skin and eyes.
- Fire may produce hydrogen chloride, phenolic smoke and other toxic/corrosive gases.
- Runoff may carry toxic chlorinated phenol contamination.
- Avoid all skin contact and control contaminated runoff.
Chemical Identity & Physical Properties
Clear to amber or dark brown liquid with a strong, characteristic phenolic odor. May be viscous depending on specific isomer composition.
| Also known as | chlorinated phenolsmonochlorophenoldichlorophenoltrichlorophenolchlorophenol isomers |
| Appearance | Clear to amber or dark brown liquid with a strong, characteristic phenolic odor. May be viscous depending on specific isomer composition. |
| Flash Point | 121-127C (250-260F) typical range depending on chlorination degree |
| Boiling Point | 174-253C (345-487F) depending on specific chlorophenol isomer |
| Vapor Density | 4.4-9.0 (heavier than air) depending on isomer |
| Water Reactivity | No significant reaction with water, but slightly soluble; may contaminate waterways |
Fireground Response Guidance — UN 2021
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 skin contact.
Isolation & Evacuation
First Actions for a UN 2021 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 dust, vapor, fumes, mist or smoke and avoid skin or eye contact.
- Do not touch damaged containers or 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 release area and expand the perimeter for fire involvement, water reaction, vapor generation, dust spread or unknown product identity.
- Use ERG Guide 153, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 2021 — Chlorophenols, 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.