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NITROGEN DIOXIDEICSC: 0930 (October 2013)
Dinitrogen tetroxide (see notes)
Nitrogen tetroxide
Nitrogen peroxide
CAS #: 10102-44-0
UN #: 1067
EC Number: 233-272-6

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Not combustible but enhances combustion of other substances.    NO contact with combustible substances.    In case of fire in the surroundings, use appropriate extinguishing media.  In case of fire: keep cylinder cool by spraying with water. 

 AVOID ALL CONTACT! IN ALL CASES CONSULT A DOCTOR! 
  SYMPTOMS PREVENTION FIRST AID
Inhalation Cough. Sore throat. Shortness of breath. Dizziness. Headache. Burning sensation. Laboured breathing. Nausea. Symptoms may be delayed. See Notes.  Use breathing protection, closed system or ventilation.  Fresh air, rest. Half-upright position. Administration of oxygen may be needed. Refer immediately for medical attention. 
Skin Redness. Burning sensation. Pain. Serious skin burns.  Protective gloves. Protective clothing.  First rinse with plenty of water for at least 15 minutes, then remove contaminated clothes and rinse again. Refer immediately for medical attention. 
Eyes Redness. Pain. Severe burns.  Wear safety goggles or eye protection in combination with breathing protection.  Rinse with plenty of water for several minutes (remove contact lenses if easily possible). Refer immediately for medical attention. 
Ingestion Burns in mouth and throat.  Do not eat, drink, or smoke during work.  Rinse mouth. Do NOT induce vomiting. Refer immediately for medical attention. 

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Evacuate danger area! Consult an expert! Personal protection: gas-tight chemical protection suit including self-contained breathing apparatus. Ventilation. Do NOT absorb in saw-dust or other combustible absorbents. Remove vapour with fine water spray. Neutralize used water with chalk or soda. 

According to UN GHS Criteria

cylinder;gasflam circlecorrskull;toxiccancer;health haz
DANGER
Contains gas under pressure; may explode if heated
May cause or intensify fire; oxidizer
Fatal if inhaled
Causes severe skin burns and eye damage
Causes damage to lungs
Causes damage to the lungs through prolonged or repeated exposure 

Transportation
UN Classification
UN Hazard Class: 2.3; UN Subsidiary Risks: 5.1 and 8 

STORAGE
Ventilation along the floor. Separated from combustible substances and reducing agents. 
PACKAGING
 
NITROGEN DIOXIDE ICSC: 0930
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
REDDISH-BROWN GAS OR BROWN OR YELLOW LIQUID WITH PUNGENT ODOUR. 

Physical dangers
The gas is heavier than air. 

Chemical dangers
The substance is a strong oxidant. It reacts violently with combustible and reducing materials. Reacts with water. This produces nitric acid and nitric oxide. Attacks many metals in the presence of water. 

Formula: NO2
Molecular mass: 46.0
Boiling point: 21.2°C
Melting point: -11.2°C
Relative density (water = 1): 1.45 (liquid)
Solubility in water: reaction
Vapour pressure, kPa at 20°C: 96
Relative vapour density (air = 1): 1.58  


EXPOSURE & HEALTH EFFECTS

Routes of exposure
The substance can be absorbed into the body by inhalation. 

Effects of short-term exposure
The substance is corrosive to the eyes, skin and respiratory tract. Exposure at high concentrations could cause asphyxiation due to swelling in the throat. Inhalation of the gas or vapour may cause lung oedema. See Notes. Exposure far above the OEL could cause death. The effects may be delayed. Severe effects may occur following a prolonged symptom-free period. Medical observation is indicated. 

Inhalation risk
A harmful concentration of this gas in the air will be reached very quickly on loss of containment. 

Effects of long-term or repeated exposure
The substance may have effects on the lungs. This may result in impaired functions and decreased resistance to infection. 


OCCUPATIONAL EXPOSURE LIMITS
TLV: 0.2 ppm as TWA; A4 (not classifiable as a human carcinogen).
MAK: 0.95 mg/m3, 0.5 ppm; peak limitation category: I(1); carcinogen category: 3; pregnancy risk group: D.
EU-OEL: 0.96 mg/m3, 0.5 ppm as TWA; 1.91 mg/m3, 1 ppm as STEL 

ENVIRONMENT
 

NOTES
The commercial brown liquid under pressure is an equilibrium mixture of nitrogen dioxide and the colourless nitrogen tetroxide (CAS 10544-72-6).
Non irritant concentration may cause lung oedema.
The symptoms of lung oedema often do not become manifest until a few hours have passed and they are aggravated by physical effort. Rest and medical observation are therefore essential.
Immediate administration of an appropriate inhalation therapy by a doctor, or by an authorized person, should be considered.
Rinse contaminated clothing with plenty of water because of fire hazard.
Turn leaking cylinder with the leak up to prevent escape of gas in liquid state. 

ADDITIONAL INFORMATION
  EC Classification
Symbol: O, T+; R: 8-26-34; S: (1/2)-9-26-28-36/37/39-45; Note: 5 

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    See Also:
       Toxicological Abbreviations