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Nitrogen dioxide																				Related Pages
Synonyms & Trade Names
			Dinitrogen tetroxide, Nitrogen peroxide
CAS No.
			10102-44-0
	RTECS No.
			QW9800000
	DOT ID & Guide
			1067 124

FormulaNO2
	Conversion
			1 ppm = 1.88 mg/m3
	IDLH
			13 ppmSee: 2017-202

Exposure Limits
			NIOSH RELST 1 ppm (1.8 mg/m3)
					OSHA PEL C 5 ppm (9 mg/m3) See Appendix G
	Measurement Methods
			**NIOSH** 6014;**OSHA** ID182
					
					See: NMAM or OSHA 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 Weight46.0	
	Boiling Point70°F
	Freezing Point15°F
	SolubilityReacts
	Vapor Pressure720 mmHg
	Ionization Potential9.75 eV											
Specific Gravity1.44 (Liquid at 68°F)	
	Flash PointNA
	Upper Explosive LimitNA
	Lower Explosive LimitNA
	Relative Gas Density2.62
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: 0930
					  MEDICAL TESTS: 0164

			
							

			Page last reviewed:  October 30, 2019						Content
							source: 	National Institute for Occupational Safety and Health NIOSH Pocket Guide to Chemical Hazards
Introduction
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Appendices
A – NIOSH Potential Occupational Carcinogens
B – Thirteen OSHA-Regulated Carcinogens
C – Supplementary Exposure Limits
D – Substances with No Established RELs
E – OSHA Respirator Requirements for Selected Chemicals
F – Miscellaneous Notes
G – 1989 Air Contaminants Update Project: Exposure Limits NOT in Effect
Type C & CE – Definitions for Type C and Type CE Respirators
Personal Protection and Sanitation Codes
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