September 2010
NIOSH Publication Number 2010-168c

Hydrogen selenide

Synonyms & Trade Names
Selenium dihydride, Selenium hydride
CAS No.
7783-07-5
RTECS No.
MX1050000
DOT ID & Guide
2202 117 (anhydrous)
Formula
H2Se
Conversion
1 ppm = 3.31 mg/m3
IDLH
1 ppm
See: 7783075
Exposure Limits
NIOSH REL
: TWA 0.05 ppm (0.2 mg/m3)
OSHA PEL
: TWA 0.05 ppm (0.2 mg/m3)
Measurement Methods

None available
Physical Description
Colorless gas with an odor resembling decayed horseradish. [Note: Shipped as a liquefied compressed gas.]
MW:
81.0
BP:
-42°F
FRZ:
-87°F		 Sol(73°F): 0.9% VP(70°F): 9.5 atm
IP:
9.88 eV
Fl.P:
NA (Gas)
UEL:
?
LEL:
?
RGasD:
2.80
Flammable Gas
Incompatibilities & Reactivities
Strong oxidizers, acids, water, halogenated hydrocarbons
Exposure Routes
inhalation, skin and/or eye contact
Symptoms
irritation eyes, nose, throat; nausea, vomiting, diarrhea; metallic taste, garlic breath; dizziness, lassitude (weakness, exhaustion); liquid: frostbite; in animals: pneumonitis; liver damage
Target Organs
Eyes, respiratory system, liver
Personal Protection/Sanitation
(See protection codes)
Skin: Frostbite
Eyes: Frostbite
Wash skin: No recommendation
Remove: When wet (flammable)
Change: No recommendation
Provide: Frostbite wash
First Aid
(See procedures)
Eye: Frostbite
Skin: Frostbite
Breathing: Respiratory support
Respirator Recommendations

NIOSH/OSHA

Up to 0.5 ppm:
(APF = 10) Any supplied-air respirator

Up to 1 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   See ICSC CARD: 0284