Nitrous Oxide

1Identification

Name

Nitrous Oxide

IUPAC name

nitrous oxide

CAS number

10024-97-2

EC number

233-032-0

Molecular formula

N2O

Molecular weight

44.013 g/mol

InChIKey

GQPLMRYTRLFLPF-UHFFFAOYSA-N

SMILES

[N-]=[N+]=O

PubChem CID

948

Synonyms

nitrous oxide, Laughing gas, Dinitrogen oxide, Dinitrogen monoxide, Factitious air, nitrogen protoxide, Nitrogen oxide (N2O), Hyponitrous acid anhydride, Nitrogen hypoxide, Stickdioxyd, oxyde nitreux, Oxido nitroso, Gas, Laughing, protoxyde d'azote

Recommended uses

• Nitrous oxide has been used as an anesthetic since 1844. It has also been used as a foaming agent for whipped cream, as an oxidant in organic chemical production and as a component of rocket fuel. Occupational exposures have been measured in the 400 to 3000 ppm range without anesthetic waste gas scavenging and 50 ppm with waste gas scavenging. [ACGIH]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• To oxidize organic compounds at temperatures greater than 300 °C; to make nitrites from alkali metals at their boiling points; in rocket fuel formulations (with carbon disulfide); in the preparation of whipped cream.
  Hazardous Substances Data Bank (HSDB)
• Anesthetic in dentistry and surgery, propellant gas in food aerosols, leak detection.
  Hazardous Substances Data Bank (HSDB)
• Other Semiconductor and photovoltaic agent Etching agent
  EPA Chemical Data Reporting (CDR)
• Semiconductor and photovoltaic agent
  EPA Chemical Data Reporting (CDR)

Use categories: Food additives · Animal Drugs -> FDA Approved Animal Drug Products (Green Book) -> Active Ingredients · Food Additives -> ANTIOXIDANT; FOAMING_AGENT; PROPELLANT -> JECFA Functional Classes · Cosmetics -> Propellant

Description

• Nitrous Oxide can cause developmental toxicity and female reproductive toxicity according to The National Institute for Occupational Safety and Health (NIOSH).
  California Office of Environmental Health Hazard Assessment (OEHHA)
• Nitrous oxide is a colorless, sweet-tasting gas. It is also known as "laughing gas". Continued breathing of the vapors may impair the decision making process. It is noncombustible but it will accelerate the burning of combustible material in a fire. It is soluble in water. Its vapors are heavier than air. Exposure of the container to prolonged heat or fire can cause it to rupture violently and rocket. It is used as an anesthetic, in pressure packaging, and to manufacture other chemicals.
  CAMEO Chemicals
• Nitrous oxide, refrigerated liquid appears as a colorless liquid. Density 1.22 g / cm3 at its boiling point of -89 °C. Boils to give a colorless gas that is sweet-smelling and moderately toxic. The gas has narcotic effects when inhaled (laughing gas). Shipped under refrigeration. Vapor pressure is at about 745 psig at 70 °F. Used to freeze foods and to manufacture other chemicals.
  CAMEO Chemicals

2Hazard identification

Signal word

Danger

Pictograms

GHS03, GHS04, GHS07

Classification source

European Chemicals Agency (ECHA)

Precautionary statements

Other reported classifications

4 classification records exist across sources. Differences usually reflect purity, physical form or impurities.

Health hazards

• Inhalation causes intense analgesia; concentrations of over 40-60% cause loss of consciousness preceded by hysteria. Contact of liquid with eyes or skin causes frostbite burn. (USCG, 1999)
  CAMEO Chemicals
• Excerpt from ERG Guide 122 [Gases - Oxidizing (Including Refrigerated Liquids)]: Vapors may cause dizziness or asphyxiation without warning, especially when in closed or confined areas. Contact with gas, liquefied gas or cryogenic liquids may cause burns, severe injury and/or frostbite. Fire may produce irritating and/or toxic gases. (ERG, 2024)
  CAMEO Chemicals
• · Vapors may cause dizziness or asphyxiation without warning, especially when in closed or confined areas. · Contact with gas, liquefied gas or cryogenic liquids may cause burns, severe injury and/or frostbite. · Fire may produce irritating and/or toxic gases.
  Emergency Response Guidebook (ERG)

Fire hazards

• Behavior in Fire: Will support combustion, and may increase intensity of fire. Containers may explode when heated. (USCG, 1999)
  CAMEO Chemicals
• Excerpt from ERG Guide 122 [Gases - Oxidizing (Including Refrigerated Liquids)]: Substance does not burn but will support combustion. Some may react explosively with fuels. May ignite combustibles (wood, paper, oil, clothing, etc.). Vapors from liquefied gas are initially heavier than air and spread along ground. Runoff may create fire or explosion hazard. Containers may explode when heated. Ruptured cylinders may rocket. (ERG, 2024)
  CAMEO Chemicals
• · Substance does not burn but will support combustion. · Some may react explosively with fuels. · May ignite combustibles (wood, paper, oil, clothing, etc.). · Vapors from liquefied gas are initially heavier than air and spread along ground. · Runoff may create fire or explosion hazard. · Containers may explode when heated. · Ruptured cylinders may rocket.
  Emergency Response Guidebook (ERG)

Hazards summary

• Nitrous oxide is a simple asphyxiant; it has caused neuropathy when abused for its euphoric effects. The TLV basis is CNS impairment, hematologic effect, and embryo/fetal damage. Rats exposed for 2 or more days to 80% NO and 20% O2 have altered hematopoiesis. At 1000 ppm, NO inactivates vitamin B12. [ACGIH] Possible frostbite from contact with liquid; [NIOSH] In substance abuse cases with peripheral neuropathy, nitrous oxide was administered at 300,000 to 800,000 ppm (30-80%) for 30-60 minutes per day, 2-7 days a week for 3 months to several years. [CHEMINFO]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

3Composition / information on ingredients

This page describes the pure substance. Commercial products may be solutions or mixtures. Check Section 3 of your supplier's SDS for concentrations and other ingredients.

4First-aid measures

• Excerpt from NIOSH Pocket Guide for Nitrous oxide: Eye: FROSTBITE - If eye tissue is frozen, seek medical attention immediately; if tissue is not frozen, immediately and thoroughly flush the eyes with large amounts of water for at least 15 minutes, occasionally lifting the lower and upper eyelids. If irritation, pain, swelling, lacrimation, or photophobia persist, get medical attention as soon as possible. Skin: FROSTBITE - If frostbite has occurred, seek medical attention immediately; do NOT rub the affected areas or flush them with water. In order to prevent further tissue damage, do NOT attempt to remove frozen clothing from frostbitten areas.
  CAMEO Chemicals
• General First Aid: · Call 911 or emergency medical service. · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination. · Move victim to fresh air if it can be done safely. · Administer oxygen if breathing is difficult. · If victim is not breathing: -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance. -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).
  Emergency Response Guidebook (ERG)
• (General first aid procedures) Eye: Frostbite - If eye tissue is frozen, seek medical attention immediately; if tissue is not frozen, immediately and thoroughly flush the eyes with large amounts of water for at least 15 minutes, occasionally lifting the lower and upper eyelids. If irritation, pain, swelling, lacrimation, or photophobia persist, get medical attention as soon as possible. Skin: Frostbite - Compressed gases may create low temperatures when they expand rapidly. Leaks and uses that allow rapid expansion may cause a frostbite hazard. Wear appropriate personal protective clothing to prevent the skin from becoming frozen. Breathing: Fresh air
  The National Institute for Occupational Safety and Health (NIOSH)

Symptoms of exposure

• Euphoria. Drowsiness. Dizziness. Unconsciousness.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• ON CONTACT WITH LIQUID: FROSTBITE.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• dyspnea (breathing difficulty); drowsiness, headache; asphyxia; reproductive effects; liquid: frostbite
  The National Institute for Occupational Safety and Health (NIOSH)

5Fire-fighting measures

• Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.
  Hazardous Substances Data Bank (HSDB)
• Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary.
  Hazardous Substances Data Bank (HSDB)
• Use water spray to cool unopened containers.
  Hazardous Substances Data Bank (HSDB)

Hazardous combustion products

• Special hazards arising from the substance or mixture: Nitrogen oxides (NOx)
  Hazardous Substances Data Bank (HSDB)

6Accidental release measures

Isolation and evacuation

• Excerpt from ERG Guide 122 [Gases - Oxidizing (Including Refrigerated Liquids)]: IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 100 meters (330 feet) in all directions. LARGE SPILL: Consider initial downwind evacuation for at least 500 meters (1/3 mile). FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)
  CAMEO Chemicals
• Immediate precautionary measure · Isolate spill or leak area for at least 100 meters (330 feet) in all directions. Large Spill · Consider initial downwind evacuation for at least 500 meters (1/3 mile). Fire · If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.
  Emergency Response Guidebook (ERG)

Spill cleanup

• Evacuate danger area! Consult an expert! Personal protection: self-contained breathing apparatus. Ventilation. NEVER direct water jet on liquid. If liquid: do NOT absorb in saw-dust or other combustible components.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas; Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains; Methods and materials for containment and cleaning up: Contain spillage, and then collect with an electrically protected vacuum cleaner or by wet-brushing and place in container for disposal according to local regulations.
  Hazardous Substances Data Bank (HSDB)
• Evacuate danger area! Consult an expert! Ventilation. If in liquid state: do NOT absorb in saw-dust or other combustible absorbents. NEVER direct water jet on liquid.
  Hazardous Substances Data Bank (HSDB)
• Spill handling: If in a building, evacuate building and confine vapors by closing doors and shutting down HVAC systems. Restrict persons not wearing protective equipment from area of spill or leak until cleanup is complete. Remove all ignition sources. Ventilate area of spill or leak to disperse the gas. Wear chemical protective suit with self-contained breathing apparatus to combat spills. Stay upwind and use water spray to "knock down" vapor; contain runoff. Stop the flow of gas, if it can be done safely from a distance. If source is a cylinder and the leak cannot be stopped in place, remove the leaking cylinder to a safe place and repair leak or allow cylinder to empty.
  Hazardous Substances Data Bank (HSDB)

7Handling and storage

• Fireproof if in building. Separated from reducing agents and combustible substances. Cool.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Keep container tightly closed in a dry and well-ventilated place. Contents under pressure.
  Hazardous Substances Data Bank (HSDB)
• Store in a location separate from other materials, especially flammables and combustibles. ... Nitrous oxide must be stored to avoid contact with organic peroxides, ammonia, carbon monoxide, hydrogen, hydrogen sulfide, and phosphine, since violent reactions occur. Cylinders of nitrous oxide should be stored in a cool, preferably fire-resistant area, away from heat sources.
  Hazardous Substances Data Bank (HSDB)
• Cylinders containing 50% nitrous oxide and 50% oxygen should be protected from the cold to prevent separation of the gases. Cylinders exposed to temperatures lower than -7 °C should be rolled at room temperature to ensure mixing or alternatively stores horizontally for 24 hours at a temperature of not less than 10 °C.
  Hazardous Substances Data Bank (HSDB)

8Exposure controls / personal protection

Personal protective equipment

• Excerpt from NIOSH Pocket Guide for Nitrous oxide: Skin: FROSTBITE - Compressed gases may create low temperatures when they expand rapidly. Leaks and uses that allow rapid expansion may cause a frostbite hazard. Wear appropriate personal protective clothing to prevent the skin from becoming frozen. Eyes: FROSTBITE - Wear appropriate eye protection to prevent eye contact with the liquid that could result in burns or tissue damage from frostbite. Wash skin: No recommendation is made specifying the need for washing the substance from the skin (either immediately or at the end of the work shift).
  CAMEO Chemicals
• Eye/face protection: Face shield and safety glasses. Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).
  Hazardous Substances Data Bank (HSDB)
• Skin protection: Handle with gloves.
  Hazardous Substances Data Bank (HSDB)
• Body Protection: Complete suit protecting against chemicals. The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.
  Hazardous Substances Data Bank (HSDB)

Respirator recommendations

• Important additional information about respirator selection
  The National Institute for Occupational Safety and Health (NIOSH)

9Physical and chemical properties

10Stability and reactivity

Reactivity

• NITROUS OXIDE is a weak oxidizing agent. Nonflammable but supports combustion. Can explode at high temperature (after vaporization). Vapors can undergo a violent reaction with aluminum, boron, hydrazine, lithium hydride, phenyllithium, phosphine, sodium, tungsten carbide [Bretherick, 5th ed., 1995, p. 1686]. Contact of the cold liquefied gas with water may result in vigorous or violent boiling. If the water is hot, a liquid "superheat" explosion may occur. Pressures may build to dangerous levels if liquefied gas contacts water in a closed container [Handling Chemicals Safely 1980].
  CAMEO Chemicals
• NITROUS OXIDE, REFRIGERATED LIQUID is a weak oxidizing agent. Nonflammable but supports combustion. Can explode at high temperature (after vaporization). Vapors may undergo a violent reaction with aluminum, boron, hydrazine, lithium hydride, phenyllithium, phosphine, sodium, tungsten carbide [Bretherick, 5th ed., 1995, p. 1686]. Contact of the cold liquefied gas with water may result in vigorous or violent boiling. If the water is hot, a liquid "superheat" explosion may occur. Pressures may build to dangerous levels if liquefied gas contacts water in a closed container [Handling Chemicals Safely 1980].
  CAMEO Chemicals
• No rapid reaction with air. No rapid reaction with water.
  CAMEO Chemicals

Incompatible materials and hazardous reactions

• Incompatible materials: Aluminum, Borane/boron oxides, Hydrazine, Strong reducing agents
  Hazardous Substances Data Bank (HSDB)
• Violent reactions with organic peroxides, hydrazine, hydrogen, hydrogen sulfide, lithium, boron, lithium hydride, sodium, aluminum, phosphine ... Strong oxidizer above 300 °C ...
  Hazardous Substances Data Bank (HSDB)
• Powdered aluminum burns in the vapor of ... nitrous oxide ... .
  Hazardous Substances Data Bank (HSDB)

Chemical stability

• Stable under recommended storage conditions.
  Hazardous Substances Data Bank (HSDB)

11Toxicological information

Target organs

• respiratory system, central nervous system, reproductive system
  The National Institute for Occupational Safety and Health (NIOSH)

Short-term exposure effects

• The liquid may cause frostbite. The substance may cause effects on the central nervous system. This may result in lowering of consciousness.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Long-term exposure effects

• The substance may have effects on the bone marrow and nervous system. May cause reproductive toxicity in humans.
  ILO-WHO International Chemical Safety Cards (ICSCs)

12Ecological information

Not available in the public sources we compile. Check Section 12 of the supplier's SDS.

13Disposal considerations

• SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.
  Hazardous Substances Data Bank (HSDB)
• Product: Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable. Offer surplus and non-recyclable solutions to a licensed disposal company. Contact a licensed professional waste disposal service to dispose of this material; Contaminated packaging: Dispose of as unused product.
  Hazardous Substances Data Bank (HSDB)

14Transport information

UN numbers: UN 1070, UN 2201

Shipping name

• UN 1070; Nitrous oxide
  Hazardous Substances Data Bank (HSDB)
• UN 2201; Nitrous oxide, refrigerated liquid
  Hazardous Substances Data Bank (HSDB)

DOT hazard class

• Nitrous oxide
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172
• UN1070
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172
• Div 2.2 Non-flammable compressed gas (49 eCFR § 173.115)
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172

DOT label

• Non-Flammable Gas Oxidizer
  CAMEO Chemicals

UN classification

• UN Hazard Class: 2.2; UN Subsidiary Risks: 5.1
  ILO-WHO International Chemical Safety Cards (ICSCs)

Emergency Response Guidebook

• 2201 122
  Emergency Response Guidebook (ERG)
• 1070 122
  Emergency Response Guidebook (ERG)

How DOT hazard classes work →

15Regulatory information

• Substance added directly to human food affirmed as generally recognized as safe (GRAS).
  Hazardous Substances Data Bank (HSDB)

Overview of SDS regulations (OSHA HazCom, WHMIS, REACH/CLP) →

16Other information

Compiled from PubChem CID 948 and the sources it aggregates (attributed inline). Data retrieved 2026-10-12. This summary describes the pure substance and is not a supplier SDS.