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Chemical Datasheet

NITROGEN TETROXIDE

2.3 - Poisonous gas 5.1 - Oxidizer 8 - Corrosive
Chemical Identifiers | Hazards | Response Recommendations | Physical Properties | Regulatory Information | Alternate Chemical Names

Chemical Identifiers

The Chemical Identifier fields include common identification numbers, the NFPA diamond, U.S. Department of Transportation hazard labels, and a general description of the chemical. The information in CAMEO Chemicals comes from a variety of data sources.
CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 10544-72-6   (NITROGEN TETROXIDE)
  • Poison Gas
  • Oxidizer
  • Corrosive
NIOSH Pocket Guide International Chem Safety Card
none none
NFPA 704
Diamond Hazard Value Description
0
3 0
ox
Blue Health 3 Can cause serious or permanent injury.
Red Flammability 0 Will not burn under typical fire conditions.
Yellow Instability 0 Normally stable, even under fire conditions.
White Special OX Possesses oxidizing properties.
(NFPA, 2010)
General Description
Red-brown liquid with a sharp, unpleasant chemical odor. Low-boiling (boiling point 21.15°C) and held as a liquid by compression. Density 1.448 g / cm3. Consists of an equilibrium mixture of brown NO2 (nitrogen dioxide) and colorless N2O4 (dinitrogen tetroxide). Evolves poisonous brown vapors. Cylinders and ton containers may not be equipped with a safety relief device. Prolonged exposure of the containers to fire or heat may result in their violent rupturing and rocketing.

Hazards

The Hazard fields include special hazard alerts, air and water reactions, fire hazards, health hazards, a reactivity profile, and details about reactive groups assignments and potentially incompatible absorbents. The information in CAMEO Chemicals comes from a variety of data sources.
Reactivity Alerts
Air & Water Reactions
Reacts with water to form nitric acid and nitric oxide.
Fire Hazard
Special Hazards of Combustion Products: Produces toxic gas when heated.

Behavior in Fire: Does not burn, but supports combustion of combustible materials such as wood. May cause fire or explode on contact with other materials. (USCG, 1999)
Health Hazard
Very concentrated fumes produce coughing, choking, headache, nausea, pain in chest and abdomen; otherwise, few symtoms appear at time of exposure. After symptom-free period of 5-72 hours, pulmonary edema gradually develops, causing fatigue, restlessness, coughing, difficulty in breathing, frothy expectoration, mental confusion, lethargy, bluish skin, and weak, rapid pulse. Since NOX interferes with gas exchange in lungs, unconscious- ness and death by asphyxiation can result, usually within a few hours after onset of pulmonary edema. (USCG, 1999)
Reactivity Profile
Liquid NITROGEN TETROXIDE is an oxidizing agent consisting of an equilibrium mixture of colorless dinitrogen tetraoxide (N2O4) and red-brown nitrogen dioxide (NO2). The exact composition of the mixture depends on the temperature with higher temperature favoring conversion to NO2. Vaporizes readily to give NO2, also an oxidizing agent. Noncombustible but can accelerate the burning of combustible materials. Reacts with reducing agents to generate heat and products that may be gaseous (causing pressurization of closed containers). The products may themselves be capable of further reactions (such as combustion in the air). Reacts with alkalis to form nitrates and nitrites [Merck 11th ed. 1989]. Corrodes steel if wet, but can be stored in steel cylinders if dry [Merck]. Reacts explosively with liquid ammonia even at very low temperatures (below its freezing point) [Mellor, 1940, Vol. 8, 54]. Reacts energetically with boron trichloride [Mellor, 1946, Vol. 5, 132]. Mixtures with metal carbonyls are hypergolic (enflame immediately). Mixtures with halocarbons, hydrazine derivatives, heterocyclic bases (pyridine), isopropyl nitrite/propyl nitrite, active metals (magnesium, calcium, etc.), nitroaromatics, nitrogen trichloride, phosphorus, triethylamine, unsaturated hydrocarbons may react explosively. Accidental mixing with hot cyclohexane caused an explosion [MCA Case History 128. 1962]. A mixture with acetonitrile and indium showed no evidence of change for a time and then detonated when shaken (ascribed to the catalyzed oxidation of acetonitrile) [Chem. & Ind., 1958, 1004]. Mixture with alcohols produced a violent explosion [Chem. Eng. News, 1955, 33, 2372]. Vapor reacts with barium oxide incandescently [Mellor, 1940, Vol. 8, 545]. A slow reaction between the vapor and formaldehyde became explosive near 180°C [Trans. Faraday Soc. 45:767-770. 1949]. Manganese and potassium both ignite in the vapor [Ann. Chem. et Phys.(2) 2:317]. The vapor and ozone react with the evolution of light and often explode when mixed [J. Chem. Phys. 18:366. 1920].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below. More info about absorbents, including situations to watch out for...

Response Recommendations

The Response Recommendation fields include isolation and evacuation distances, as well as recommendations for firefighting, non-fire response, protective clothing, and first aid. The information in CAMEO Chemicals comes from a variety of data sources.
Isolation and Evacuation
Excerpt from ERG Guide 124 [Gases - Toxic and/or Corrosive - Oxidizing]:

As an immediate precautionary measure, isolate spill or leak area for at least 100 meters (330 feet) in all directions.

SPILL: See ERG Table 1 - Initial Isolation and Protective Action Distances on the UN/NA 1067 datasheet.

FIRE: If tank, rail car or tank truck 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, 2016)
Firefighting
Fire Extinguishing Agents: Stop flow of gas (USCG, 1999)
Non-Fire Response
Excerpt from ERG Guide 124 [Gases - Toxic and/or Corrosive - Oxidizing]:

Fully encapsulating, vapor-protective clothing should be worn for spills and leaks with no fire. Do not touch or walk through spilled material. Keep combustibles (wood, paper, oil, etc.) away from spilled material. Stop leak if you can do it without risk. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Do not direct water at spill or source of leak. If possible, turn leaking containers so that gas escapes rather than liquid. Prevent entry into waterways, sewers, basements or confined areas. Isolate area until gas has dispersed. Ventilate the area. (ERG, 2016)
Protective Clothing
Rubber gloves; safety goggles and face shield; protective clothing; acid gas canister respirator or self-contained breathing apparatus. (USCG, 1999)
DuPont Tychem® Suit Fabrics
Tychem® Fabric Legend
QS = Tychem 2000 SFR
QC = Tychem 2000
SL = Tychem 4000
C3 = Tychem 5000
TF = Tychem 6000
TP = Tychem 6000 FR
BR = Tychem 9000
RC = Tychem RESPONDER® CSM
TK = Tychem 10000
RF = Tychem 10000 FR
Testing Details
The fabric permeation data was generated for DuPont by independent testing laboratories using ASTM F739, EN369, EN 374-3, EN ISO 6529 (method A and B) or ASTM D6978 test methods. Normalized breakthrough times (the time at which the permeation rate is equal to 0.1 µg/cm2/min) reported in minutes. All liquid chemicals have been tested between approximately 20°C and 27°C unless otherwise stated. A different temperature may have significant influence on the breakthrough time; permeation rates typically increase with temperature. All chemicals have been tested at a concentration of greater than 95% unless otherwise stated. Unless otherwise stated, permeation was measured for single chemicals. The permeation characteristics of mixtures can deviate considerably from the permeation behavior of the individual chemicals. Chemical warfare agents (Lewisite, Sarin, Soman, Sulfur Mustard, Tabun and VX Nerve Agent) have been tested at 22°C and 50% relative humidity per military standard MIL-STD-282.
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP BR RC TK RF
Nitrogen tetroxide (95%, liquid, 0° C) 10544-72-6 Liquid >480 >480 >480 >480
Nitrogen tetroxide (>95%, gas) 10544-72-6 Vapor 90 90 90 420
Nitrogen tetroxide (>95%, liquid, 21° C) 10544-72-6 Liquid 450
> indicates greater than.
A blank cell indicates the fabric has not been tested. The fabric may or may not offer barrier.

Special Warnings from DuPont

  1. Serged and bound seams are degraded by some hazardous liquid chemicals, such as strong acids, and should not be worn when these chemicals are present.
  2. CAUTION: This information is based upon technical data that DuPont believes to be reliable. It is subject to revision as additional knowledge and experience are gained. DuPont makes no guarantee of results and assumes no obligation or liability...
    ... in connection with this information. It is the user's responsibility to determine the level of toxicity and the proper personal protective equipment needed. The information set forth herein reflects laboratory performance of fabrics, not complete garments, under controlled conditions. It is intended for informational use by persons having technical skill for evaluation under their specific end-use conditions, at their own discretion and risk. Anyone intending to use this information should first verify that the garment selected is suitable for the intended use. In many cases, seams and closures have shorter breakthrough times and higher permeation rates than the fabric. Please contact DuPont for specific data. If fabric becomes torn, abraded or punctured, or if seams or closures fail, or if attached gloves, visors, etc. are damaged, end user should discontinue use of garment to avoid potential exposure to chemical. Since conditions of use are outside our control, we make no warranties, express or implied, including, without limitation, no warranties of merchantability or fitness for a particular use and assume no liability in connection with any use of this information. This information is not intended as a license to operate under or a recommendation to infringe any patent or technical information of DuPont or others covering any material or its use.

(DuPont, 2018)

First Aid
INHALATION: remove patient to fresh air and have him breathe as deeply as possible; call a doctor; enforce complete rest for 24-48 hours; keep warm; give oxygen if coughing starts; physician may administer morphine (10 mg.)

EYES AND

SKIN: flush with water for at least 15 min. (USCG, 1999)

Physical Properties

The Physical Property fields include properties such as vapor pressure and boiling point, as well as explosive limits and toxic exposure thresholds. The information in CAMEO Chemicals comes from a variety of data sources.
Chemical Formula:
  • N2O4
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: Not flammable (USCG, 1999)
Melting Point: 11.8 ° F (USCG, 1999)
Vapor Pressure: 1551 mm Hg (USCG, 1999)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 1.45 at 68 ° F (USCG, 1999)
Boiling Point: 70.1 ° F at 760 mm Hg (USCG, 1999)
Molecular Weight: 92.02 (USCG, 1999)
Water Solubility: data unavailable
Ionization Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

Final AEGLs for Nitrogen Tetroxide (10544-72-6)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 0.25 ppm 10 ppm 17 ppm
30 minutes 0.25 ppm 7.6 ppm 13 ppm
60 minutes 0.25 ppm 6.2 ppm 10 ppm
4 hours 0.25 ppm 4.1 ppm 7 ppm
8 hours 0.25 ppm 3.5 ppm 5.7 ppm
(NAC/NRC, 2017)

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Nitrogen tetroxide (10544-72-6) 0.25 ppm 6.2 ppm 10 ppm
(DOE, 2016)

Regulatory Information

The Regulatory Information fields include information from the U.S. Environmental Protection Agency's Title III Consolidated List of Lists, the U.S. Department of Homeland Security's Chemical Facility Anti-Terrorism Standards, and the U.S. Occupational Safety and Health Administration's Process Safety Management of Highly Hazardous Chemicals Standard List (see more about these data sources).

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Nitrogen dioxide 10544-72-6 10 pounds @

(EPA List of Lists, 2015)

DHS Chemical Facility Anti-Terrorism Standards (CFATS)

RELEASE THEFT SABOTAGE
Chemical of Interest CAS Number Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Dinitrogen tetroxide 10544-72-6 3.80 % 15 pounds WME

(DHS, 2007)

OSHA Process Safety Management (PSM) Standard List

Chemical Name CAS Number Threshold Quantity (TQ)
Nitrogen Tetroxide (also called Nitrogen Peroxide) 10544-72-6 250 pounds

(OSHA, 2011)

Alternate Chemical Names

This section provides a listing of alternate names for this chemical, including trade names and synonyms.