MSDS for Liquid Oxygen
Identification
Product Name: Liquid Oxygen
Chemical Formula: O2
Synonyms: LOX, Oxygen, Refrigerated Liquid
CAS Number: 7782-44-7
Intended Use: Used in healthcare, metallurgy, chemical synthesis, and aerospace.
Manufacturer Contact: Emergency phone and address from supplier’s documentation required on site.
Hazard Identification
Hazard Class: Oxidizing gas
Physical State: Cryogenic liquid
Main Risks: Accelerates combustion, explosion hazard with flammable/organic materials, severe burns and frostbite on contact
GHS Pictograms: Gas cylinder, flame over circle
Signal Word: Danger
Hazard Statements: May cause or intensify fire, oxidizer that makes all surrounding materials more combustible, can rapidly freeze exposed body tissue.
Precautionary Statements: Keep away from combustibles, handle only outdoors or in well-ventilated areas.
Composition / Information on Ingredients
Ingredient: Oxygen
Concentration: 99% minimum
Impurities: Trace inert gases (argon, nitrogen), below hazardous thresholds in most sources
Hazardous Constituents: No other added components or stabilizers.
First Aid Measures
Inhalation: Remove victim to fresh air, provide oxygen mask or ventilation as medical judgment directs, seek medical attention if symptoms persist.
Skin Contact: Remove contaminated clothing, flush affected skin with lukewarm water, avoid rubbing, cover lightly with sterile dressing, seek immediate medical attention for frostbite.
Eye Contact: Flush gently with lukewarm water for several minutes, do not attempt to warm eyes forcibly, contact an ophthalmologist promptly.
Ingestion: Not considered a route of exposure for liquid oxygen.
Additional Recommendations: Rescuers must use appropriate personal protective equipment, move victims carefully away from spill/cryogenic area because of risk to rescuers.
Fire-Fighting Measures
Extinguishing Media: Liquid oxygen itself does not burn but reacts violently with many combustibles; use large quantities of water for fire control if materials around are involved.
Hazards Combustion Products: Enhances burning of combustibles, supports extremely rapid oxidation.
Special Fire Fighting Procedures: Evacuate area, keep upwind, use self-contained breathing apparatus, remove ignition sources, prevent flow of oxygen into fire, try to stop leak if safe. All clothing and equipment must be oxygen-service clean.
Unusual Fire Hazards: Blanketing or containing liquid oxygen increases risk of violent reaction if exposed to heat or incompatible materials.
Accidental Release Measures
Personal Precautions: Evacuate unnecessary personnel, ventilate area, avoid direct contact with liquid and cold vapors, wear full cryogenic and oxygen-compatible PPE.
Environmental Precautions: Prevent large releases from entering drains, sewers, or confined spaces because of rapid displacement of air and freezing hazards.
Cleanup Methods: Allow spilled liquid to evaporate in a secure, well-ventilated area, isolate spill area, restrict access until cold vapors dissipate.
Emergency Procedures: Inform fire services, have oxygen-compatible firefighting equipment ready in case nearby combustibles ignite.
Handling and Storage
Handling: Use only equipment and containers specifically cleaned and rated for oxygen service, keep away from greases, oils, organic liquids, avoid mechanical shock, never handle with materials containing hydrocarbons or organics on your skin, clothing, or tools.
Storage: Store in carefully ventilated areas away from combustibles, separate from fuel gases, maintain vertical orientation for containers, use proper signage, ensure temperature control to minimize pressure build-up.
Requirements: All fittings must be leak-tested, electrical devices in storage area should be explosion-proof, secure cylinders to prevent tipping.
Exposure Controls and Personal Protection
Exposure Limits: None assigned for oxygen as an oxidizer; hazard arises from increased fire risk, not direct toxicity.
Engineering Controls: Use with well-ventilated systems, preferably with local exhaust ventilation at transfer points.
Personal Protection: Wear cryogenic gloves, face shield, safety goggles, oxygen-compatible clothing, avoid synthetic fibers that can create fire risk.
Respiratory Protection: Not typically needed, unless oxygen-enriched atmosphere risk or insufficient oxygen develops; use NIOSH-approved positive pressure respirator in emergencies.
Thermal Protection: Shield all exposed skin against possible splashes or cold-vapor contact.
Physical and Chemical Properties
Appearance: Pale blue, clear cryogenic liquid at atmospheric pressure
Odor: Odorless in both gas and liquid forms
Boiling Point: -183°C (-297°F)
Melting Point: -219°C (-362°F)
Vapor Pressure: High at room temperature
Solubility in Water: Slightly soluble
Vapor Density (air = 1): 1.1
Specific Gravity (liquid): 1.14
Flammability: Not flammable, but causes intense burning of other substances
Critical Temperature: -118.6°C
Expansion Ratio: 1:860 (liquid to gas)
Other: Contact may embrittle many common metals and plastics.
Stability and Reactivity
Chemical Stability: Stable at normal temperatures when segregated from impurities
Conditions to Avoid: Contact with organic materials, greases, oils, most reducing agents, or combustible materials, even dust
Incompatible Materials: Hydrocarbons, phosphorus, powdered metals, strong reducing agents, cellulose-based substances
Hazardous Reactions: Violent explosion risk when mixed with fuels, instantaneous fire on ignition sources, gaseous expansion creating physical hazards
Hazardous Decomposition Products: None under recommended use and storage
Toxicological Information
Routes of Exposure: Inhalation, skin, eye contact for cold-liquid or vapor
Acute Effects: Severe tissue damage from frostbite after skin or eye contact, increased fire or explosion risk, may dry and irritate mucous membranes, breathing refrigerated oxygen gas may cause lung irritation.
Chronic Effects: Continuous exposure to oxygen-enriched atmospheres increases fire hazard but is not linked to systemic toxicity; no evidence for carcinogenicity, mutagenicity, or reproductive harm.
Symptoms of Overexposure: Frostbite damage, respiratory irritation, possible lung injury from extreme cold vapors.
Ecological Information
Environmental Effects: Oxygen itself does not pose a direct environmental hazard, but sudden releases may harm small animals or plant tissue through rapid chilling or displacement of air.
Persistence and Degradability: Oxygen rapidly dissipates and mixes with ambient air; no toxic residues remain.
Bioaccumulation Potential: None
Mobility in Soil: Not relevant for a gas and cryogenic liquid that evaporates quickly through atmosphere.
Other Adverse Effects: Changes local fire risk and oxidation rates for organic matter in release zones.
Disposal Considerations
Disposal Methods: Allow remaining liquid to vaporize using proper open ventilation, avoid confined spaces, do not pour onto ground in vegetated or combustible areas.
Requirements: Observe local and national waste disposal regulations, empty containers must be depressurized and returned to supplier or disposed by qualified companies.
Precautions: Keep all handling areas free of oils and combustibles before, during, and after disposal steps; avoid environmental oxygen enrichment beyond normal levels.
Transport Information
UN Number: UN1073
Proper Shipping Name: Oxygen, refrigerated liquid
Class: 2.2 (non-flammable gas), 5.1 (oxidizer)
Packaging Group: Not assigned
Labeling Requirements: Oxidizing gas, cryogenic liquid
Transportation Precautions: Secure upright, protect valves, avoid impacts, transport only in approved containers, no exposure to high heat, store separately from flammable loads.
Regulatory Information
OSHA Status: Subject to Hazard Communication Standard; containers and areas require hazard-specific labeling
EPA SARA Title III: Not listed as a hazardous substance for environmental impacts but must follow fire-code regulations
Other Regulation: DOT regulations for hazardous materials, CGA recommendations for compressed gases, NFPA rating for oxidizing and reactivity, additional local fire safety ordinances
Special Notes: Facilities storing or handling above set thresholds require site safety programs and compliance checks from regulators.
