September 2010
NIOSH Publication Number 2010-168c

Nitrous oxide

Synonyms & Trade Names
Dinitrogen monoxide, Hyponitrous acid anhydride, Laughing gas
CAS No.
10024-97-2
RTECS No.
QX1350000
DOT ID & Guide
1070 122 (refrigerated liquid)
Formula
N2O
Conversion
1 ppm = 1.80 mg/m3
IDLH
N.D.
See: IDLH INDEX
Exposure Limits
NIOSH REL
*: TWA 25 ppm (46 mg/m3) (TWA over the time exposed) [*Note: REL for exposure to waste anesthetic gas.]
OSHA PEL
: none
Measurement Methods

NIOSH ID166
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
Fl.P:
NA
UEL:
NA
LEL:
NA
RGasD:
1.53
Nonflammable Gas, but supports combustion at elevated temperatures.
Incompatibilities & Reactivities
Aluminum, boron, hydrazine, lithium hydride, phosphine, sodium
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
Personal Protection/Sanitation
(See protection codes)
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
Respirator Recommendations

Not available.

Important additional information about respirator selection

See also: INTRODUCTION   See ICSC CARD: 0067