UN 1972 — Natural gas, refrigerated liquid (cryogenic liquid)
Placard: Flammable Gas. ERG Guide 115. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1972 is Natural gas, refrigerated liquid (cryogenic liquid), a refrigerated flammable natural gas entry assigned to ERG Guide 115. LNG releases can rapidly form cold vapor clouds that may ignite or flash back.
Hazard overview: EXTREMELY FLAMMABLE refrigerated natural gas; rapid vaporization can form large ignitable vapor clouds. Cold vapor may initially stay low and travel along the ground before warming and rising. Vapors may travel to ignition sources and flash back.
Response guidance: For a UN 1972 incident, verify the product with shipping papers, container markings, SDS and ERG Guide 115. Establish incident command, isolate the area, stay upwind, control ignition or downwind hazards, cool exposed containers from a protected distance when appropriate and base entry decisions on monitoring and local SOP.
Firefighter training notes: Training for UN 1972 should emphasize flammable gas vapor travel, flashback, source isolation, BLEVE/rocket hazards, container cooling, cryogenic/frostbite risk where applicable and ignition control. Use ERG 115, SDS and local SOP.
Regulatory context: Natural gas, refrigerated liquid (cryogenic liquid) is regulated as a hazardous material for transportation and emergency response purposes. Storage, workplace exposure, emergency planning, spill reporting and waste handling requirements vary by exact product, concentration, quantity and jurisdiction. Verify current requirements through shipping papers, SDS, container markings and applicable DOT, OSHA, EPA, NFPA, state or local authority guidance.
Storage & handling: Natural gas, refrigerated liquid (cryogenic liquid) should be stored in approved cryogenic containers in a ventilated area away from heat, ignition sources where flammable, confined low spots and physical damage. Provide pressure relief and oxygen/flammable gas monitoring where appropriate.
UN 1972 Quick Details
Common Hazards of UN 1972
- EXTREMELY FLAMMABLE refrigerated natural gas; rapid vaporization can form large ignitable vapor clouds.
- Cold vapor may initially stay low and travel along the ground before warming and rising.
- Vapors may travel to ignition sources and flash back.
- Contact with LNG or cold vapor can cause severe frostbite and cryogenic burns.
- Containers exposed to heat may vent, rupture or BLEVE/rocket.
- LNG does not react chemically with water, but water contact can increase rapid boiling and vapor generation.
- Do not extinguish a flowing gas fire unless the fuel source can be stopped safely.
Chemical Identity & Physical Properties
Colorless to pale yellow cryogenic liquid with a faint natural gas odor. Boils at approximately -161°C (-258°F) and produces a white vapor cloud when released.
| Also known as | LNGLiquefied Natural GasCryogenic Natural GasMethane, refrigerated liquid |
| CAS Number | 8006-14-2 |
| Appearance | Colorless to pale yellow cryogenic liquid with a faint natural gas odor. Boils at approximately -161°C (-258°F) and produces a white vapor cloud when released. |
| Flash Point | -188C (-306F) |
| Boiling Point | -161C (-258F) |
| Vapor Density | 0.6 initially as gas (lighter than air when warmed) |
| Water Reactivity | No significant reaction; may cause rapid boiling and splashing due to extreme temperature difference |
Fireground Response Guidance — UN 1972
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for vapor, fire or confined-space exposure. Wear flame-resistant protection and insulated/cryogenic gloves and face protection where liquefied gas contact is possible.
Isolation & Evacuation
First Actions for a UN 1972 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.
- Avoid breathing vapors, gas, smoke, mist or dust and avoid skin or eye contact.
- Protect against cryogenic frostbite and avoid low/confined areas until oxygen and gas readings are checked.
- Eliminate ignition sources if safe and keep vapors and runoff out of drains, sewers, basements and low areas.
- Do not touch damaged containers or spilled/released material unless properly trained and wearing appropriate protective equipment.
- Ventilate closed spaces before entering, but only if properly trained, equipped, monitored and authorized by incident command.
- Isolate the release or spill area and expand the perimeter for fire involvement, vapor accumulation, cylinder/tank heating or unknown product identity.
- Use ERG Guide 115, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 1972 — Natural gas, refrigerated liquid (cryogeUse 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.