UN 1182 — Ethyl chloroformate
Placard: Toxic. ERG Guide 155. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Ethyl chloroformate is a highly flammable and toxic substance that requires careful handling. It is a colorless to pale yellow liquid with a pungent, irritating odor that is highly volatile and corrosive.
Hazard overview: Ethyl chloroformate is highly flammable and can be easily ignited by heat, sparks, or flames. Vapors form explosive mixtures with air, posing explosion hazards indoors, outdoors, and in sewers.
Response guidance: In case of a spill, isolate the area immediately and use alcohol-resistant foam, CO2, or dry chemical for extinguishing. Wear a Level B minimum with SCBA and a chemical-resistant suit required, as the material is corrosive and toxic.
UN 1182 Quick Details
Common Hazards of UN 1182
- HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
- Vapors form explosive mixtures with air: indoors, outdoors and sewers explosion hazards.
- Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas
- Vapors may travel to source of ignition and flash back.
- Those substances designated with a (P) may polymerize explosively when heated or involved in a fire.
- Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff.
- Corrosives in contact with metals may evolve flammable hydrogen gas.
- Containers may explode when heated or if contaminated with water.
Chemical Identity & Physical Properties
Ethyl chloroformate is a colorless to pale yellow liquid with a pungent, irritating odor that is highly volatile and corrosive.
| Also known as | Chloroformic acid ethyl esterEthyl chlorocarbonateCarbonochloridic acid ethyl esterECF |
| CAS Number | 541-41-3 |
| Appearance | Colorless to pale yellow liquid with a pungent, irritating odor. Highly volatile and corrosive. |
| Flash Point | -4°C (25°F) |
| Boiling Point | 93-95°C (199-203°F) |
| Vapor Density | 3.8 (heavier than air) |
| Water Reactivity | Reacts with water releasing HCl gas and CO2; avoid direct water contact on material |
Fireground Response Guidance — UN 1182
Extinguishing Media
PPE Requirements
Wear a Level B minimum with SCBA and a chemical-resistant suit required, as ethyl chloroformate is corrosive and toxic.
Isolation & Evacuation
First Actions for a UN 1182 Incident
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Ventilate closed spaces before entering, but only if properly trained and equipped.
- Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
- For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.
- For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind
📋 Copy & Share Field Card
UN 1182 — Ethyl chloroformateUse 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.