UN 2626 — Chloric acid, aqueous solution, with not more than 10% chloric acid
Placard: Oxidizer. ERG Guide 140. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2626 is Chloric acid, aqueous solution, with not more than 10% chloric acid, an oxidizing corrosive acid solution assigned to ERG Guide 140. Concentration and contamination control are critical.
Hazard overview: OXIDIZING chloric acid solution; can intensify fire involving combustibles. Contact with organic materials, reducing agents, metals or strong acids/bases can cause violent reaction. May release chlorine oxides, chlorine and oxygen-containing gases if heated or decomposed.
Response guidance: For UN 2626, isolate the area, remove combustibles and prevent organic/reducing-agent contamination. Use oxidizer-compatible tactics, cool containers from protection and contain acidic/oxidizing runoff.
Firefighter training notes: Training for UN 2626 should emphasize oxidizer contamination control, acid burns, incompatible organics/reducing agents, decomposition signs, container cooling and runoff containment. Use ERG 140, SDS and local SOP.
Regulatory context: Chloric acid, aqueous solution, with not more than 10% chloric acid 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: Chloric acid, aqueous solution, with not more than 10% chloric acid should be stored in compatible acid/oxidizer-rated containers away from organics, fuels, reducing agents, metals where incompatible, heat and contamination.
UN 2626 Quick Details
Common Hazards of UN 2626
- OXIDIZING chloric acid solution; can intensify fire involving combustibles.
- Contact with organic materials, reducing agents, metals or strong acids/bases can cause violent reaction.
- May release chlorine oxides, chlorine and oxygen-containing gases if heated or decomposed.
- Corrosive solution can burn eyes, skin and respiratory tissue.
- Runoff may be acidic, oxidizing and harmful to waterways.
- Containers may rupture when heated or contaminated.
- Exact concentration must be verified; higher concentrations can be much more reactive.
Chemical Identity & Physical Properties
Colorless to pale yellow aqueous solution with a sharp, acrid odor. Liquid at room temperature.
| Also known as | Chloric acid solutionHydrogen chlorate solutionChlorate acid aqueous |
| CAS Number | 7790-93-4 |
| Appearance | Colorless to pale yellow aqueous solution with a sharp, acrid odor. Liquid at room temperature. |
| Flash Point | Not applicable (non-flammable oxidizer) |
| Boiling Point | Approximately 100C (212F) for dilute solutions |
| Vapor Density | Not applicable (aqueous solution) |
| Water Reactivity | Already an aqueous solution; highly reactive oxidizer that can react violently with organic materials and reducing agents |
Fireground Response Guidance — UN 2626
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and chemical-resistant protective clothing. Level A may be needed for heavy vapor, fuming, splash risk or unknown concentrations.
Isolation & Evacuation
First Actions for a UN 2626 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, gas, mist, smoke or fumes and avoid skin or eye contact.
- Keep fuels, organics, reducing agents and combustible contamination away from the oxidizer.
- Do not touch damaged containers or spilled material without proper training and PPE.
- Keep water or moisture contact controlled when it may increase reaction, fuming or gas generation.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 140, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2626 — Chloric acid, aqueous solution, with notUse 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.