NIOSH Pocket Guide to Chemical Hazards

Nitrous oxide

CAS 10024-97-2


RTECS QX1350000
Synonyms & Trade Names
Dinitrogen monoxide, Hyponitrous acid anhydride, Laughing gas
DOT ID & Guide
1070 122
2201 122 (refrigerated liquid)


NIOSH REL*: TWA 25 ppm (46 mg/m3) (TWA over the time exposed) [*Note: REL for exposure to waste anesthetic gas.]
OSHA PEL: none
IDLH N.D. See: IDLH INDEX Conversion 1 ppm = 1.80 mg/m3
Physical Description
Colorless gas with a slightly sweet odor. [inhalation anesthetic] [Note: Shipped as a liquefied compressed gas.]
MW: 44.0
BP: -127°F
FRZ: -132°F
Sol(77°F): 0.1%
VP: 51.3 atm
IP: 12.89 eV
RGasD: 1.53

Fl.P: NA

Nonflammable Gas, but supports combustion at elevated temperatures.
Incompatibilities & Reactivities
Aluminum, boron, hydrazine, lithium hydride, phosphine, sodium
Measurement Methods
NIOSH 3800, 6600; OSHA ID166
See: NMAM or OSHA Methods
Personal Protection & Sanitation (See protection)
Skin: Frostbite
Eyes: Frostbite
Wash skin: No recommendation
Remove: No recommendation
Change: No recommendation
Provide: Frostbite wash
First Aid (See procedures)
Eye: Frostbite
Skin: Frostbite
Breathing: Fresh air

Important additional information about respirator selection
Respirator Recommendations Not available.
Exposure Routes inhalation, skin and/or eye contact (liquid)
Symptoms Dyspnea (breathing difficulty); drowsiness, headache; asphyxia; reproductive effects; liquid: frostbite
Target Organs respiratory system, central nervous system, reproductive system
See also: INTRODUCTION   See ICSC CARD: 0067