UN 2720 — Chromium nitrate
Placard: Oxidizer. ERG Guide 141. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Chromium nitrate is an oxidizing chromium salt, often encountered as hydrated crystals. It can accelerate burning and create contaminated runoff.
Hazard overview: Chromium nitrate is an oxidizing solid. The main fire problem is intensification of burning when it contacts fuels or combustible contamination.
Response guidance: Remove combustibles from the area, keep contaminated runoff contained and cool exposed containers from a protected location. Do not let product mix with oils, fuels or organics.
Firefighter training notes: Train crews to identify Chromium nitrate by UN number, placard, ERG guide and SDS before choosing entry, isolation or extinguishment tactics.
Regulatory context: Use UN 2720, ERG 141, SDS, container labels and shipping papers to confirm the exact hazard profile and protective action distances.
Storage & handling: Store in closed, compatible containers away from heat, ignition sources and incompatible materials; keep the area ventilated and protected from damage.
UN 2720 Quick Details
Common Hazards of UN 2720
- Oxidizer; it can intensify fire even though the material itself is not fuel.
- Contact with combustibles, organics, oils, fuels or reducing agents may cause ignition or rapid burning.
- Fire may produce irritating and toxic fumes.
- Dust or solution contact may irritate skin, eyes and respiratory tract.
- Runoff can carry toxic metal or oxidizing contamination into waterways.
- Containers exposed to heat may rupture.
- Contamination can make the material unstable or more reactive.
Chemical Identity & Physical Properties
Purple to violet hygroscopic crystalline solid; commonly encountered as a hydrate and odorless.
| Also known as | Chromic nitrateChromium(III) nitrateChromium trinitrateNitric acid chromium(III) salt |
| CAS Number | 13548-38-4 |
| Appearance | Purple to violet crystalline solid or hygroscopic crystals. May be encountered as nonahydrate form. Odorless. |
| Flash Point | Not applicable (oxidizing solid) |
| Boiling Point | Decomposes at 100-125C (212-257F) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | Soluble in water with heat release during dissolution |
Fireground Response Guidance — UN 2720
Extinguishing Media
PPE Requirements
Use SCBA for fire or dust conditions with chemical-resistant gloves, eye protection and protective clothing.
Isolation & Evacuation
First Actions for a UN 2720 Incident
- Call 911 and the emergency response number shown on shipping papers or container documents.
- Keep unauthorized personnel away and establish an initial isolation perimeter.
- Stay upwind, uphill and upstream; avoid low areas where vapors or runoff may collect.
- Avoid breathing vapors, dust, smoke or mist and prevent skin and eye contact.
- Keep combustibles, fuels, organic material, oils and reducing agents away from the release area.
- Do not touch damaged containers or spilled material without appropriate chemical PPE.
- Ventilate confined spaces only when personnel are trained, monitored and properly equipped.
- Use ERG guidance, SDS, shipping papers and air monitoring before committing crews.
📋 Copy & Share Field Card
UN 2720 — Chromium nitrateUse 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.