UN 1791 — Hypochlorite solution
Placard: Corrosive. ERG Guide 154. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1791 is Hypochlorite solution, a Class 8 corrosive oxidizing solution assigned to ERG Guide 154. It is often a bleach-type liquid that can release chlorine gas if mixed with acids.
Hazard overview: UN 1791 presents corrosive liquid, oxidizer, chlorine gas and incompatible-mixing hazards. Keep it away from acids, ammonia, amines, fuels, organics and reducing agents.
Response guidance: For a UN 1791 incident, responders should verify the product with shipping papers, package markings, SDS and ERG Guide 154. Establish incident command, isolate the area, stay upwind, prevent incompatible contact, control runoff and choose entry or fire-control actions based on monitoring, SDS and local SOP.
Firefighter training notes: Training for UN 1791 should emphasize chlorine gas release from acid contact, chloramine risk with ammonia/amines, oxidizer incompatibilities, vapor control and runoff containment. Use ERG 154, SDS and local SOP.
Regulatory context: Hypochlorite solution 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 concentration, formulation, 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: Hypochlorite solution should be stored in compatible corrosion-resistant containers away from acids, ammonia compounds, fuels, organics, reducing agents, heat and sunlight. Prevent leaks, decomposition and mixing with incompatible materials.
UN 1791 Quick Details
Common Hazards of UN 1791
- CORROSIVE oxidizing solution; inhalation, ingestion or skin/eye contact may cause injury.
- Mixing with acids can release chlorine gas.
- Mixing with ammonia or amines may release chloramine-type irritating gases.
- Can intensify fire involving some combustibles or react with reducing agents and organics.
- Heating or decomposition may produce toxic chlorine-type gases.
- Runoff may be corrosive, oxidizing and harmful to waterways.
- Containers may rupture or fail when heated.
Chemical Identity & Physical Properties
Clear to pale yellow-green liquid with characteristic chlorine-like odor. Aqueous solution of alkaline hypochlorite salts, typically 5-15% concentration for household bleach.
| Also known as | sodium hypochlorite solutionbleach solutionliquid chlorine bleachCloroxJavelle water |
| CAS Number | 7681-52-9 |
| Appearance | Clear to pale yellow-green liquid with characteristic chlorine-like odor. Aqueous solution of alkaline hypochlorite salts, typically 5-15% concentration for household bleach. |
| Flash Point | Not applicable (non-flammable aqueous solution) |
| Boiling Point | Approximately 100-110°C (212-230°F), varies with concentration |
| Vapor Density | Not applicable (aqueous solution, heavier than water) |
| Water Reactivity | Miscible with water; may release chlorine gas when mixed with acids or ammonia |
Fireground Response Guidance — UN 1791
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for vapor, mist, fire or confined-space exposure. Wear chemical-resistant gloves, boots, eye/face protection and protective clothing selected from SDS for corrosive liquid contact.
Isolation & Evacuation
First Actions for a UN 1791 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 or spray and avoid skin or eye contact.
- Keep acids, ammonia, amines, fuels, organics and reducing agents away from the material.
- Do not touch or walk through spilled material unless properly trained and wearing appropriate protective equipment.
- 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, fire involvement, water reaction or unknown concentration is present.
- Use ERG Guide 154, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 1791 — Hypochlorite solutionUse 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.