UN 2653 — Benzyl iodide
Placard: Toxic. ERG Guide 156. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2653 is Benzyl iodide, a toxic halogenated material assigned to ERG Guide 156. Hydrogen halide fumes and toxic runoff are key concerns.
Hazard overview: TOXIC halogenated material; inhalation, ingestion or skin contact may cause severe injury. Vapor, dust or liquid may irritate or burn eyes, skin and respiratory tissue. Combustible material: may burn but does not ignite readily.
Response guidance: For UN 2653, isolate the area, avoid skin contact and use SCBA where dust, vapor, mist or fire is present. Prevent spread of contaminated runoff, cool containers from protection and verify controls with SDS and ERG 156.
Firefighter training notes: Training for UN 2653 should emphasize toxic exposure routes, skin absorption, SCBA use, dust/vapor control, decontamination, runoff containment and SDS verification. Use ERG 156, SDS and local SOP.
Regulatory context: Benzyl iodide is regulated as a hazardous material for transport and emergency response. Storage, exposure, spill reporting, waste and fire-code duties depend on quantity, concentration and jurisdiction; verify shipping papers, SDS and local authority requirements.
Storage & handling: Benzyl iodide should be stored in tightly closed compatible containers with ventilation, secondary containment, restricted access and separation from heat, oxidizers and incompatible materials.
UN 2653 Quick Details
Common Hazards of UN 2653
- TOXIC halogenated material; inhalation, ingestion or skin contact may cause severe injury.
- Vapor, dust or liquid may irritate or burn eyes, skin and respiratory tissue.
- Combustible material: may burn but does not ignite readily.
- Moisture or heating may release hydrogen halide fumes or corrosive/toxic decomposition products.
- Heavy vapors may collect in low or confined areas when heated.
- Runoff may be toxic, corrosive and persistent.
- Avoid skin contact and contaminated clothing exposure.
Chemical Identity & Physical Properties
Colorless to pale yellow liquid with a pungent, irritating odor. Darkens on exposure to light and air. Denser than water and insoluble in water.
| Also known as | Benzyl iodidePhenylmethyl iodideAlpha-iodotulueneIodomethylbenzene(Iodomethyl)benzene |
| CAS Number | 620-05-3 |
| Appearance | Colorless to pale yellow liquid with a pungent, irritating odor. Darkens on exposure to light and air. Denser than water and insoluble in water. |
| Flash Point | Not readily combustible, estimated >93C (>200F) |
| Boiling Point | 93C (199F) at 24 mmHg, decomposes above 218C (424F) |
| Vapor Density | 7.7 (much heavier than air) |
| Water Reactivity | Reacts slowly with water releasing hydroiodic acid (HI), a corrosive and toxic gas. May accelerate at elevated temperatures. |
Fireground Response Guidance — UN 2653
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.
Isolation & Evacuation
First Actions for a UN 2653 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 or spilled material without proper training and PPE.
- Prevent contaminated dust, liquid, runoff and decontamination waste from spreading.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 156, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2653 — Benzyl iodideUse 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.