UN 1048 — Hydrogen bromide, anhydrous
Placard: Toxic Gas. ERG Guide 125. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1048 is Hydrogen bromide, anhydrous, a Class 2 toxic and corrosive gas assigned to ERG Guide 125. It fumes in moist air and forms strongly corrosive acid mist or solution on contact with moisture.
Hazard overview: UN 1048 presents toxic inhalation and corrosive acid-gas hazards. Vapors can injure eyes, skin and respiratory tissue, and moisture contact forms hydrobromic acid mist or solution that can damage equipment, surfaces and waterways.
Response guidance: For a UN 1048 incident, responders should confirm the product using shipping papers, cylinder markings, SDS and ERG Guide 125. Establish incident command, isolate the area, stay upwind, avoid vapor contact, use air monitoring when available and consult ERG Table 1 when applicable.
Firefighter training notes: Training for UN 1048 should emphasize toxic inhalation risk, corrosive vapor exposure, SCBA discipline, Table 1 protective actions and cylinder leak-control limitations. Common errors include relying on odor, entering low areas without monitoring, applying water to a reactive leak and selecting splash PPE without respiratory protection.
Regulatory context: Hydrogen bromide, anhydrous is regulated as a hazardous material for transportation and emergency response purposes. Cylinder, workplace exposure, storage, reporting and environmental requirements may vary by product, quantity and jurisdiction. Responders should verify current requirements through shipping papers, SDS, cylinder markings, facility documents and applicable DOT, OSHA, EPA, NFPA, state or local authority guidance.
Storage & handling: Hydrogen bromide, anhydrous should be stored in compatible containers or cylinders in a cool, dry, well-ventilated area with toxic/corrosive gas controls, leak detection where required and segregation from incompatible materials. Protect containers from heat, corrosion, impact, valve damage and unauthorized access.
UN 1048 Quick Details
Common Hazards of UN 1048
- TOXIC and/or CORROSIVE; may be fatal if inhaled.
- Gas or vapor may severely irritate or burn eyes, skin and respiratory tissue.
- Contact with liquefied gas may cause frostbite and chemical injury.
- Fire may produce irritating, corrosive and/or toxic gases.
- Runoff from fire control or vapor suppression may be corrosive or environmentally hazardous.
- Vapors may collect in low or confined areas depending on product and release conditions.
- Containers may rupture or rocket when heated.
Chemical Identity & Physical Properties
Colorless to faint yellow gas with a sharp, pungent, irritating odor. Fumes strongly in moist air forming white clouds of hydrobromic acid mist.
| Also known as | HBrHydrobromic acid gasAnhydrous hydrobromic acidBromane |
| CAS Number | 10035-10-6 |
| Appearance | Colorless to faint yellow gas with a sharp, pungent, irritating odor. Fumes strongly in moist air forming white clouds of hydrobromic acid mist. |
| Flash Point | Not applicable (non-flammable gas) |
| Boiling Point | -67C (-88F) |
| Vapor Density | 2.8 (heavier than air) |
| Water Reactivity | Dissolves in water forming corrosive hydrobromic acid solution; exothermic reaction with heat generation |
Fireground Response Guidance — UN 1048
Extinguishing Media
PPE Requirements
Positive-pressure SCBA is required for suspected toxic gas exposure. Chemical-protective clothing should be selected using SDS, monitoring results, leak conditions and incident command; Level A may be needed for close entry into unknown or high-concentration toxic/corrosive vapor.
Isolation & Evacuation
First Actions for a UN 1048 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.
- Do not touch damaged cylinders, tanks, valves or released material unless properly trained and equipped.
- Avoid breathing gas, vapor, mist or fire gases.
- Many toxic or liquefied gases may spread along the ground and collect in low or confined areas.
- Ventilate closed spaces before entering, but only if properly trained, equipped and authorized by incident command.
- Isolate the spill or leak area for at least 100 meters (330 feet) in all directions.
- For highlighted materials, consult ERG Table 1 for Initial Isolation and Protective Action Distances.
- For non-highlighted materials, increase the precautionary distance downwind based on release size, weather, monitoring and incident command.
📋 Copy & Share Field Card
UN 1048 — Hydrogen bromide, anhydrousUse 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.