UN 1163 — Dimethylhydrazine, unsymmetrical
Placard: Toxic. ERG Guide 131. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Dimethylhydrazine, unsymmetrical is a highly toxic and flammable liquid that requires careful handling. It is used in various industrial applications, including as a rocket fuel component.
Hazard overview: The substance is highly toxic and may be fatal if inhaled, ingested, or absorbed through the skin. Prolonged exposure can cause severe irritation or burns to the skin and eyes.
Response guidance: In case of an emergency, evacuate the area immediately and call for professional help. Wear Level A protective gear, including a self-contained breathing apparatus and chemical-resistant suit, to minimize exposure.
UN 1163 Quick Details
Common Hazards of UN 1163
- TOXIC; may be fatal if inhaled, ingested or absorbed through skin.
- Inhalation or contact with some of these materials will irritate or burn skin and eyes.
- Methyl chloroacetate (UN2295) is an eye irritant/lachrymator (causes flow of tears).
- Fire will produce irritating, corrosive and/or toxic gases.
- Vapors may cause dizziness or asphyxiation, especially when in closed or confined areas.
- Runoff from fire control or dilution water may cause environmental contamination.
- HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
- Vapors may form explosive mixtures with air.
Chemical Identity & Physical Properties
Dimethylhydrazine, unsymmetrical is a colorless to pale yellow fuming liquid with a fishy ammonia-like odor, and it is highly flammable and hygroscopic.
| Also known as | UDMH1,1-DimethylhydrazineDimazineHydrazine, 1,1-dimethyl-N,N-Dimethylhydrazine |
| CAS Number | 57-14-7 |
| Appearance | Colorless to pale yellow fuming liquid with a fishy ammonia-like odor. Highly flammable and hygroscopic. |
| Flash Point | -15C (5F) |
| Boiling Point | 63C (145F) |
| Vapor Density | 2.1 (heavier than air) |
| Water Reactivity | Soluble in water; no violent reaction but forms toxic solution |
Fireground Response Guidance — UN 1163
Extinguishing Media
PPE Requirements
Level A protective gear, including a self-contained breathing apparatus and chemical-resistant suit, is recommended to handle the substance due to its high toxicity and absorption through skin.
Isolation & Evacuation
First Actions for a UN 1163 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 for at least 50 meters (150 feet) in all directions.
- 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 1163 — Dimethylhydrazine, unsymmetricalUse 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.