UN 1488 — Potassium nitrite
Placard: Oxidizer. ERG Guide 140. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Potassium nitrite is a highly reactive substance that can accelerate burning when involved in a fire. It is essential to exercise extreme caution when handling this substance.
Hazard overview: Potassium nitrite can accelerate burning when involved in a fire and may decompose explosively when heated or involved in a fire. This can lead to severe consequences if not handled properly.
Response guidance: In the event of a fire involving potassium nitrite, use dry chemical, sand, or water spray for cooling only. Avoid using organic materials or combustibles as they can exacerbate the situation.
UN 1488 Quick Details
Common Hazards of UN 1488
- These substances will accelerate burning when involved in a fire.
- Some may decompose explosively when heated or involved in a fire.
- May explode from heat or contamination.
- Some will react explosively with hydrocarbons (fuels).
- May ignite combustibles (wood, paper, oil, clothing, etc.).
- Containers may explode when heated.
- Runoff may create fire or explosion hazard.
- Inhalation, ingestion or contact (skin, eyes) with vapors or substance may cause severe injury, burns or
Chemical Identity & Physical Properties
Potassium nitrite appears as a white to slightly yellowish crystalline powder or granular solid, odorless, and hygroscopic, which may cake when exposed to moisture.
| Also known as | Nitrous acid potassium saltPotassium nitrite (KNO2)Saltpeter (potassium nitrite) |
| CAS Number | 7758-09-0 |
| Appearance | White to slightly yellowish crystalline powder or granular solid. Odorless. Hygroscopic and may cake when exposed to moisture. |
| Flash Point | Not applicable (oxidizing solid) |
| Boiling Point | Not applicable (decomposes above 440C/824F) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | Soluble in water forming alkaline solution; no violent reaction but may release toxic nitrogen oxides if contaminated or heated |
Fireground Response Guidance — UN 1488
Extinguishing Media
PPE Requirements
When handling potassium nitrite, wear a Level B minimum personal protective equipment (PPE) with SCBA required in fire or decomposition situations.
Isolation & Evacuation
First Actions for a UN 1488 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 in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
- Consider initial downwind evacuation for at least 100 meters (330 feet).
📋 Copy & Share Field Card
UN 1488 — Potassium nitriteUse 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.