UN 1702 — Tetrachloroethane
Placard: Toxic. ERG Guide 151. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1702 is Tetrachloroethane, a highly toxic halogenated liquid assigned to ERG Guide 151. It is dense, generally nonflammable and can create heavy-vapor and contaminated-runoff hazards.
Hazard overview: UN 1702 presents toxic vapor, skin contact and dense-liquid contamination hazards. Heating or fire may produce hydrogen halide, phosgene-type or other toxic/corrosive gases.
Response guidance: For a UN 1702 incident, responders should verify the product with shipping papers, package markings, SDS and ERG Guide 151. Establish incident command, isolate the area, stay upwind, prevent dust, vapor or aerosol exposure, control runoff and choose entry or cleanup actions based on monitoring, SDS and local SOP.
Firefighter training notes: Training for UN 1702 should emphasize toxic exposure routes, air monitoring, PPE selection, decontamination and preventing contaminated runoff. Use ERG 151, SDS and local SOP.
Regulatory context: Tetrachloroethane 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: Tetrachloroethane should be stored in tightly closed compatible containers in a secure toxic-material area according to SDS and local hazardous materials procedures.
UN 1702 Quick Details
Common Hazards of UN 1702
- HIGHLY TOXIC halogenated liquid; inhalation, ingestion or skin absorption may cause severe injury.
- Vapors are heavier than air and may collect in low, confined or poorly ventilated areas.
- Liquid is denser than water and may sink, spreading contamination below the surface.
- Non-flammable under normal conditions, but heating or fire may produce toxic/corrosive gases.
- Skin contact and contaminated clothing can continue exposure.
- Runoff may carry toxic contamination to drains or waterways.
- Containers may rupture or fail when heated.
Chemical Identity & Physical Properties
Colorless to pale yellow liquid with a sweet, chloroform-like odor. Denser than water and relatively volatile at room temperature.
| Also known as | Acetylene tetrachlorideSym-tetrachloroethaneTCETetrachloroethane |
| CAS Number | 79-34-5 |
| Appearance | Colorless to pale yellow liquid with a sweet, chloroform-like odor. Denser than water and relatively volatile at room temperature. |
| Flash Point | Not applicable (combustible liquid, flash point data varies: approximately 76°C/169°F) |
| Boiling Point | 146°C (295°F) |
| Vapor Density | 5.8 (much heavier than air) |
| Water Reactivity | No significant reaction with water; slightly soluble |
Fireground Response Guidance — UN 1702
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and chemical protective clothing for vapor, liquid, fire or confined-space exposure. Level A may be needed for close entry or unknown concentrations; avoid all skin contact and contaminated clothing.
Isolation & Evacuation
First Actions for a UN 1702 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, mist, aerosol or smoke and avoid all skin or eye contact.
- 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 vapor, dust, aerosol, fire involvement or unknown concentration is present.
- Use ERG Guide 151, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 1702 — TetrachloroethaneUse 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.