Nitrogen dioxide
Synonyms & Trade Names
Dinitrogen tetroxide, Nitrogen peroxide
Exposure Limits
Measurement Methods
Physical Description
Yellowish-brown liquid or reddish-brown gas (above 70°F) with a pungent, acrid odor.
[Note: In solid form (below 15°F) it is found structurally as N₂O₂.]
Molecular Weight
46.0
Boiling Point
70°F
Freezing Point
15°F
Solubility
Reacts
Vapor Pressure
720 mmHg
Ionization Potential
9.75 eV
Specific Gravity
1.44 (Liquid at 68°F)
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Relative Gas Density
2.62
Noncombustible Liquid/Gas, but will accelerate the burning of combustible materials.
Incompatibilities & Reactivities
Combustible material, water, chlorinated hydrocarbons, carbon disulfide, ammonia
[Note: Reacts with water to form nitric acid.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, nose, throat; cough, mucoid frothy sputum, decreased pulmonary function, chronic bronchitis, dyspnea (breathing difficulty); chest pain; pulmonary edema, cyanosis, tachypnea, tachycardia
Target Organs
Eyes, respiratory system, cardiovascular system
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:No recommendation
Provide:Eyewash, Quick drench
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:No recommendation
Provide:Eyewash, Quick drench
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Water flush immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Eye:Irrigate immediately
Skin:Water flush immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations
NIOSH
Up to 20 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode£
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece
Emergency or planned entry into unknown concentrations or IDLH conditions:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus
Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concern¿
Any appropriate escape-type, self-contained breathing apparatus
See also
Page last reviewed: October 30, 2019
Content
source: National Institute for Occupational Safety and Health