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Nitrogen dioxide

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Synonyms & Trade Names
Dinitrogen tetroxide, Nitrogen peroxide
CAS No.
10102-44-0
RTECS No.
QW9800000
DOT ID & Guide
1067
Formula
NO?
Conversion
1 ppm = 1.88 mg/m?
IDLH
13 ppm
See: 2017-202
Exposure Limits
NIOSH REL
ST 1 ppm (1.8 mg/m?)
OSHA PEL
C 5 ppm (9 mg/m?) See Appendix G
Measurement Methods
NIOSH 6014;
OSHA
See: NMAM or
Physical Description
Yellowish-brown liquid or reddish-brown gas (above 70‘γΉσ) with a pungent, acrid odor. [Note: In solid form (below 15‘γΉσ) it is found structurally as N?O?.]
Molecular Weight
46.0
Boiling Point
70‘γΉσ
Freezing Point
15‘γΉσ
Solubility
Reacts
Vapor Pressure
720 mmHg
Ionization Potential
9.75 eV
Specific Gravity
1.44 (Liquid at 68‘γF)
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
First Aid
(See procedures)
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

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD:   MEDICAL TESTS: 0164
Page last reviewed: October 30, 2019
Content source: National Institute for Occupational Safety and Health