Nitrogen

1Identification

Name

Nitrogen

IUPAC name

molecular nitrogen

CAS number

7727-37-9

EC number

231-783-9

Molecular formula

N2

Molecular weight

28.014 g/mol

InChIKey

IJGRMHOSHXDMSA-UHFFFAOYSA-N

SMILES

N#N

PubChem CID

947

Synonyms

Nitrogen, Nitrogen gas, Molecular nitrogen, Dinitrogen, MOL Nitrogen, Nitrogeno, Nitrogen (n2), INS NO.941, INS-941, E-941, Diazyne, Nitrogen Nf, Nitrogen, NF, Nitrogen Compressed

Recommended uses

• Used as an inert purge gas in the food, chemical, and metallurgical industries; [ACGIH] Divers, caisson workers, miners, metallurgists, and workers pressurizing oil wells may be exposed to high concentrations; [LaDou, p. 559]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Petroleum Production and Refining [Category: Industry] Mining [Category: Industry] Sewer and Wastewater Treatment [Category: Industry] Metal Extraction and Refining [Category: Industry]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• For nitrogen (USEPA/OPP Pesticide Code: 128934) there are 0 labels match. /SRP: Not registered for current use in the U.S., but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses./
  Hazardous Substances Data Bank (HSDB)
• Oxidizing agent
  EPA Chemical Data Reporting (CDR)

Use categories: EPA Safer Chemical Functional Use Classes -> Uncategorized · Safer Chemical Classes -> Green circle - The chemical has been verified to be of low concern · Food additives · Food Additives -> FREEZING_AGENT; PROPELLANT -> JECFA Functional Classes

Description

• Nitrogen appears as a colorless odorless gas. Noncombustible and nontoxic. Makes up the major portion of the atmosphere, but will not support life by itself. Used in food processing, in purging air conditioning and refrigeration systems, and in pressurizing aircraft tires. May cause asphyxiation by displacement of air. Under prolonged exposure to fire or heat containers may rupture violently and rocket.
  CAMEO Chemicals
• Nitrogen, refrigerated liquid (cryogenic liquid) appears as colorless odorless liquid. Very cold. Contact may cause frostbite. Nontoxic. Under prolonged exposure to heat or fire the container may rupture violently and rocket. Used to freeze foods, to preserve whole blood and other biologicals, and as a coolant.
  CAMEO Chemicals
• Dinitrogen is an elemental molecule consisting of two trivalently-bonded nitrogen atoms. It has a role as a member of food packaging gas and a food propellant. It is a gas molecular entity, an elemental molecule and a diatomic nitrogen. It is a conjugate base of a diazynium.
  ChEBI

2Hazard identification

Signal word

Warning

Pictograms

GHS04

Classification source

European Chemicals Agency (ECHA)

Precautionary statements

Other reported classifications

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

NFPA 704 rating

• 3 - Materials that, under emergency conditions, can cause serious or permanent injury.
  Hazardous Substances Data Bank (HSDB)
• 0 - Materials that will not burn under typical fire conditions, including intrinsically noncombustible materials such as concrete, stone, and sand.
  Hazardous Substances Data Bank (HSDB)
• 0 - Materials that in themselves are normally stable, even under fire conditions.
  Hazardous Substances Data Bank (HSDB)

Health hazards

• Excerpt from ERG Guide 120 [Gases - Inert (Including Refrigerated Liquids)]: Vapors may cause dizziness or asphyxiation without warning, especially when in closed or confined areas. Vapors from liquefied gas are initially heavier than air and spread along ground. Contact with gas, liquefied gas or cryogenic liquids may cause burns, severe injury and/or frostbite. (ERG, 2024)
  CAMEO Chemicals
• Inhalation can cause asphyxiation, if atmosphere does not contain oxygen; dizziness, unconsciousness, or even death can result. Contact of liquid with skin or eyes causes frostbite burns. (USCG, 1999)
  CAMEO Chemicals
• · Vapors may cause dizziness or asphyxiation without warning, especially when in closed or confined areas. · Vapors from liquefied gas are initially heavier than air and spread along ground. · Contact with gas, liquefied gas or cryogenic liquids may cause burns, severe injury and/or frostbite.
  Emergency Response Guidebook (ERG)

Fire hazards

• Excerpt from ERG Guide 120 [Gases - Inert (Including Refrigerated Liquids)]: Non-flammable gases. Containers may explode when heated. Ruptured cylinders may rocket. (ERG, 2024)
  CAMEO Chemicals
• Behavior in Fire: Containers may explode when heated. (USCG, 1999)
  CAMEO Chemicals
• · Non-flammable gases. · Containers may explode when heated. · Ruptured cylinders may rocket.
  Emergency Response Guidebook (ERG)

Hazards summary

• A simple asphyxiant; liquid nitrogen can cause frostbite; [ACGIH]
  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 ERG Guide 120 [Gases - Inert (Including Refrigerated Liquids)]: Refer to the "General First Aid" section. Specific First Aid: Clothing frozen to the skin should be thawed before being removed. In case of contact with liquefied gas, only medical personnel should attempt thawing frosted parts. (ERG, 2024)
  CAMEO Chemicals
• INHALATION: remove to fresh air; apply artificial respiration if breathing has stopped; call physician. EYES: treat for frostbite burns caused by liquid. SKIN: treat for frostbite; soak in lukewarm water. (USCG, 1999)
  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)

Symptoms of exposure

• Unconsciousness. Weakness. Suffocation.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Suffocation.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• ON CONTACT WITH LIQUID: FROSTBITE.
  ILO-WHO International Chemical Safety Cards (ICSCs)

5Fire-fighting measures

• If material involved in fire: Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Cool all affected containers with flooding quantiites of water. Apply water from as far a distance as possible. /Nitrogen, compressed/
  Hazardous Substances Data Bank (HSDB)
• Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.
  Hazardous Substances Data Bank (HSDB)
• Wear self contained breathing apparatus for fire fighting if necessary.
  Hazardous Substances Data Bank (HSDB)

Hazardous combustion products

• Hazardous decomposition products formed under fire conditions - Carbon oxides.
  Hazardous Substances Data Bank (HSDB)

6Accidental release measures

Isolation and evacuation

• Excerpt from ERG Guide 120 [Gases - Inert (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 100 meters (330 feet). 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 100 meters (330 feet). 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

• Ventilation. Personal protection: self-contained breathing apparatus.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Soak up with inert absorbent material and dispose of as hazardous waste. Keep in suitable, closed containers for disposal.
  Hazardous Substances Data Bank (HSDB)
• Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided.
  Hazardous Substances Data Bank (HSDB)
• Use personal protective equipment. Avoid breathign vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas.
  Hazardous Substances Data Bank (HSDB)

7Handling and storage

• Fireproof if in building. Cool. Keep in a well-ventilated room.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage.
  Hazardous Substances Data Bank (HSDB)
• Since liquid nitrogen tends to cause localized oxygen enrichment due to a fractional distillation of air, containers such as formed plastics should not be used even for temporary storage of liquid nitrogen due to the resultant increase combustibility.
  Hazardous Substances Data Bank (HSDB)
• Storage temperature for liquid nitrogen: -320 °F.
  Hazardous Substances Data Bank (HSDB)

8Exposure controls / personal protection

Personal protective equipment

• Excerpt from ERG Guide 120 [Gases - Inert (Including Refrigerated Liquids)]: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing provides thermal protection but only limited chemical protection. Always wear thermal protective clothing when handling refrigerated/cryogenic liquids or solids. (ERG, 2024)
  CAMEO Chemicals
• Safety glasses or face shield; insulated gloves; long sleeves; trousers worn outside boots or over high-top shoes to shed spilled liquid; self-contained breathing apparatus where insufficient air is present. (USCG, 1999)
  CAMEO Chemicals
• Respiratory protection: Where risk assessment shows air-purifying respirators are appropriate use a full-face respirator with multi-purpose combination (US) or type ABEK (EN 14387) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face air respirator. Use respirators and components tested and approved under appropriate government standars such as NIOSH (US) or CEN (EU).
  Hazardous Substances Data Bank (HSDB)
• Handle with gloves. Gloves must be inspected prior to use. Use proper glove removal technique (without touchign glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.
  Hazardous Substances Data Bank (HSDB)

9Physical and chemical properties

10Stability and reactivity

Reactivity

• These substances undergo no chemical reactions under any known circumstances except those under extreme conditions (liquid nitrogen reacts violently in mixture with magnesium powder when a fuse is lit. Due to formation of magnesium nitride). Otherwise, they are nonflammable, noncombustible and nontoxic. They can asphyxiate.
  CAMEO Chemicals
• NITROGEN, REFRIGERATED LIQUID (CRYOGENIC LIQUID) is very unreactive. Nonflammable, noncombustible and nontoxic. Vapors can fill closed spaces and asphyxiate. Contact with water may result in vigorous or violent boiling and extremely rapid vaporization. If the water is hot, there is the possibility that a liquid "superheat" explosion may occur. Pressures may build to dangerous levels if the liquid contacts water in a closed container [Handling Chemicals Safely 1980].
  CAMEO Chemicals
• Slightly soluble in water.
  CAMEO Chemicals

Incompatible materials and hazardous reactions

• Can react violently with lithium, neodymium, titanium under the proper conditions.
  Hazardous Substances Data Bank (HSDB)
• Open vessels which contain organic materials, or which are to be hermetically sealed, should not be cooled in liquid nitrogen, but in a coolant at a higher temperature.
  Hazardous Substances Data Bank (HSDB)
• Liquid nitrogen subject to nuclear radiation (high neutron and gamma fluxes) must be kept free of oxygen to prevent explosion occurring in reactor cryostats.
  Hazardous Substances Data Bank (HSDB)

Chemical stability

• Incombustible and unreactive.
  Hazardous Substances Data Bank (HSDB)

11Toxicological information

Short-term exposure effects

• The liquid may cause frostbite.
  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)

14Transport information

UN numbers: UN 1066, UN 1977

Shipping name

• UN 1066; Nitrogen, compressed
  Hazardous Substances Data Bank (HSDB)
• UN 1977; Nitrogen, refrigerated liquid, cryogenic liquid
  Hazardous Substances Data Bank (HSDB)

DOT hazard class

• Nitrogen, compressed
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172
• UN1066
  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
  CAMEO Chemicals

UN classification

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

Emergency Response Guidebook

• 1066 120
  Emergency Response Guidebook (ERG)
• 1977 120
  Emergency Response Guidebook (ERG)

How DOT hazard classes work →

15Regulatory information

• The insecticide nitrogen is exempted from the requirements of a tolerance when used after harvest in modified atmospheres for stored product insect control on all food commodities.
  Hazardous Substances Data Bank (HSDB)
• New Active Ingredients ... includes chemicals not previously registered as pesticides, as well as pesticide active ingredients initially registered after November 1, 1984 and that currently have active product registrations. By law, these pesticides must meet new safety standards, such as those described in the Food Quality Protection Act of 1996 and, if new safety standards are met, will be reviewed again on a 15-year cycle. Liquid nitrogen is designated by EPA as a New Pesticide Active Ingredient. Active Ingredient Number: 128934; Type of Pesticide: biochemical - insecticide/termite control; Use Site: non-food use, dry wood protection; Year: 1987.
  Hazardous Substances Data Bank (HSDB)
• 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 947 and the sources it aggregates (attributed inline). Data retrieved 2026-10-12. This summary describes the pure substance and is not a supplier SDS.