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Chemical Datasheet

NITROUS OXIDE

2.2 - Non-flammable, non-poisonous gas 5.1 - Oxidizer

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 10024-97-2   (NITROUS OXIDE)
  • 1070
  • Non-Flammable Gas
  • Oxidizer
  • NTO
NIOSH Pocket Guide International Chem Safety Card
Nitrous oxide
  • NITROUS OXIDE
NFPA 704
data unavailable
General Description
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.

Hazards

Reactivity Alerts
none
Air & Water Reactions
No rapid reaction with air. No rapid reaction with water.
Fire Hazard
Behavior in Fire: Will support combustion, and may increase intensity of fire. Containers may explode when heated. (USCG, 1999)
Health Hazard
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)
Reactivity Profile
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].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

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)
Firefighting
Excerpt from ERG Guide 122 [Gases - Oxidizing (Including Refrigerated Liquids)]:

Use extinguishing agent suitable for type of surrounding fire.

SMALL FIRE: Dry chemical or CO2.

LARGE FIRE: Water spray, fog or regular foam. If it can be done safely, move undamaged containers away from the area around the fire. Damaged cylinders should be handled only by specialists.

FIRE INVOLVING TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Do not direct water at source of leak or safety devices; icing may occur. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2024)
Non-Fire Response
Excerpt from ERG Guide 122 [Gases - Oxidizing (Including Refrigerated Liquids)]:

Keep combustibles (wood, paper, oil, etc.) away from spilled material. Do not touch or walk through spilled material. Stop leak if you can do it without risk. If possible, turn leaking containers so that gas escapes rather than liquid. Do not direct water at spill or source of leak. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Prevent entry into waterways, sewers, basements or confined areas. Allow substance to evaporate. Isolate area until gas has dispersed. CAUTION: When in contact with refrigerated/cryogenic liquids, many materials become brittle and are likely to break without warning. (ERG, 2024)
Protective Clothing
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).

Remove: No recommendation is made specifying the need for removing clothing that becomes wet or contaminated.

Change: No recommendation is made specifying the need for the worker to change clothing after the workshift.

Provide: FROSTBITE WASH - Quick drench facilities and/or eyewash fountains should be provided within the immediate work area for emergency use where there is any possibility of exposure to liquids that are extremely cold or rapidly evaporating. (NIOSH, 2024)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Nitrous oxide 10024-97-2 Vapor >480 >480 >480
> indicates greater than.

Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...

(DuPont, 2024)

First Aid
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. If frostbite has NOT occurred, immediately and thoroughly wash contaminated skin with soap and water.

Breathing: FRESH AIR - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. Other measures are usually unnecessary. (NIOSH, 2024)

Physical Properties

Chemical Formula:
  • N2O
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: -131.5°F (USCG, 1999)
Vapor Pressure: 51.3 atm (NIOSH, 2024)
Vapor Density (Relative to Air): 1.53 (NIOSH, 2024) - Heavier than air; will sink
Specific Gravity: 1.266 at -128.2°F (USCG, 1999) - Denser than water; will sink
Boiling Point: -129.1°F at 760 mmHg (USCG, 1999)
Molecular Weight: 44 (USCG, 1999)
Water Solubility: 0.1 % at 77°F (NIOSH, 2024)
Ionization Energy/Potential: 12.89 eV (NIOSH, 2024)
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Nitrous oxide (10024-97-2) 910 ppm 10000 ppm 20000 ppm
(DOE, 2024)

Regulatory Information

EPA Consolidated List of Lists

No regulatory information available.

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names