UN 3455 — Cresols, solid
Placard: Toxic. ERG Guide 153. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3455 is Cresols, solid, a toxic corrosive phenolic solid assigned to ERG Guide 153. Skin absorption, phenolic burns and toxic runoff require control.
Hazard overview: TOXIC and CORROSIVE phenolic solid; inhalation, ingestion or skin absorption may cause severe injury. Cresols can absorb through skin and contaminated clothing, causing systemic toxicity and chemical burns. Combustible solid/liquid when molten; heated vapors may form ignitable mixtures.
Response guidance: For UN 3455, isolate the area, avoid skin contact and use SCBA where vapor, dust, mist or fire is present. Contain runoff and verify controls with SDS/ERG 153.
Firefighter training notes: Training for UN 3455 should emphasize exposure routes, SCBA use, vapor/dust monitoring, decontamination, runoff containment and SDS verification. Use ERG 153, SDS and local SOP.
Regulatory context: Cresols, solid is regulated as a hazardous material for transport and emergency response. Storage, reporting, exposure, waste and incident-notification duties depend on quantity, concentration, formulation and jurisdiction; verify shipping papers, SDS and authority guidance.
Storage & handling: Cresols, solid should be stored in tightly closed compatible containers with ventilation, secondary containment, restricted access and SDS-based segregation from incompatible materials.
UN 3455 Quick Details
Common Hazards of UN 3455
- TOXIC and CORROSIVE phenolic solid; inhalation, ingestion or skin absorption may cause severe injury.
- Cresols can absorb through skin and contaminated clothing, causing systemic toxicity and chemical burns.
- Combustible solid/liquid when molten; heated vapors may form ignitable mixtures.
- Molten material can cause thermal and chemical burns.
- Fire may produce phenolic smoke, carbon monoxide and irritating/toxic gases.
- Runoff may carry toxic phenolic contamination.
- Exact cresol isomer or mixture should be verified from SDS.
Chemical Identity & Physical Properties
Colorless to yellowish-brown solid or crystalline mass at room temperature with a sweet, tarry, phenolic odor. May darken on exposure to air and light.
| Also known as | MethylphenolCresylic acidHydroxytolueneTricresolCresol isomers mixture |
| Appearance | Colorless to yellowish-brown solid or crystalline mass at room temperature with a sweet, tarry, phenolic odor. May darken on exposure to air and light. |
| Flash Point | 81-86C (178-187F) depending on isomer |
| Boiling Point | 191-203C (376-397F) depending on isomer |
| Vapor Density | 3.7 (heavier than air) |
| Water Reactivity | No significant reaction; slightly soluble in water |
Fireground Response Guidance — UN 3455
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA where vapor, dust, mist, smoke or fire is present. Wear chemical-resistant gloves, boots, eye/face protection and protective clothing.
Isolation & Evacuation
First Actions for a UN 3455 Incident
- Call 911 and the emergency response number on the shipping paper, if available.
- Keep unauthorized personnel away and establish incident command.
- Stay upwind, uphill and upstream.
- Avoid breathing vapor, dust, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers, equipment or spilled material without proper training and PPE.
- Prevent contaminated liquid, dust, runoff and decontamination waste from spreading.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 153, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 3455 — Cresols, solidUse 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.