UN 2581 — Aluminum chloride, solution
Placard: Corrosive. ERG Guide 154. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2581 At a Glance
UN 2581 (Aluminum chloride, solution) is listed as DOT Class 8 Corrosive and is assigned to ERG Guide 154. Use this page to review placard data, common hazards, PPE notes, isolation context, first actions, and related UN numbers.
Aluminum chloride solution is a corrosive acidic liquid. Its strength can vary, so the SDS and shipping papers are important before choosing dilution, neutralization or cleanup tactics.
Hazard overview: Mist or splashes can cause severe chemical burns. Concentrated or heated solution may release hydrogen chloride fumes, and contact with some metals may produce hydrogen gas.
Response guidance: Keep unauthorized personnel away, control runoff and stay out of vapor or mist. Cool exposed containers from a protected location and use SDS guidance for any dilution or neutralization work.
Firefighter training notes: Train crews on acid solution behavior, metal corrosion and hydrogen potential. Emphasize SDS-based neutralization and proper splash protection.
Regulatory context: UN 2581 is Aluminum chloride, solution, Class 8 corrosive. Confirm concentration, packaging and response contact details from shipping papers and SDS.
Storage & handling: Store in compatible containers with secondary containment. Separate from bases, reactive metals, oxidizers and incompatible chemicals.
UN 2581 Quick Details
Common Hazards of UN 2581
- Corrosive acidic solution; splashes and mist can burn skin, eyes and respiratory tract.
- Concentrated solutions may release hydrogen chloride fumes, especially when heated.
- Dilution or contamination may generate heat and acidic mist depending on concentration.
- Corrosive liquid can attack metals and may generate flammable hydrogen gas.
- Fire exposure may produce irritating or corrosive gases.
- Runoff can remain acidic and damage waterways or surfaces.
- Containers may rupture when heated.
Chemical Identity & Physical Properties
Aluminum chloride solution is usually a clear to pale yellow aqueous liquid with a pungent acidic odor. Concentration affects fuming, heat release and corrosivity.
| Also known as | Aluminum trichloride solutionAluminium chloride solutionAlCl3 solutionAluminum chloride aqueous solution |
| CAS Number | 7446-70-0 |
| Appearance | Clear to pale yellow aqueous solution with a pungent, acidic odor. The solution is highly corrosive and may fume in moist air. |
| Flash Point | Not applicable (aqueous solution, non-flammable) |
| Boiling Point | Approximately 100C (212F) depending on concentration |
| Vapor Density | Not applicable (aqueous solution) |
| Water Reactivity | Already in aqueous solution; concentrated solutions react exothermically with additional water generating heat and acidic fumes |
Fireground Response Guidance — UN 2581
Extinguishing Media
PPE Requirements
Use SCBA when fumes, mist or fire gases are possible. Acid-resistant gloves, boots, suit and face protection are needed for splash exposure.
Isolation & Evacuation
First Actions for a UN 2581 Incident
- Call 911 and the emergency response number shown on shipping papers; confirm the material with ERG, SDS and container markings.
- Keep unauthorized personnel away and establish hot, warm and cold zones before entry.
- Stay upwind, uphill and upstream; avoid low areas where vapors, dust or runoff may collect.
- Avoid breathing vapors, dust, mist or decomposition products and prevent skin or eye contact.
- Do not touch damaged packages or containers unless properly trained and wearing suitable chemical PPE.
- Ventilate confined spaces only after atmospheric monitoring and only with trained, equipped personnel.
- Use ERG Guide 154, SDS, shipping papers and monitoring results for isolation, PPE and fire-control decisions.
📋 Copy & Share Field Card
UN 2581 — Aluminum chloride, 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.