NIOSH Pocket Guide to Chemical Hazards

Hydrogen selenide CAS 7783-07-5
H2Se RTECS MX1050000
Synonyms & Trade Names
Selenium dihydride, Selenium hydride
DOT ID & Guide
2202 117 (anhydrous)
NIOSH REL: TWA 0.05 ppm (0.2 mg/m3)
OSHA PEL: TWA 0.05 ppm (0.2 mg/m3)
IDLH 1 ppm Conversion 1 ppm = 3.31 mg/m3
Physical Description
Colorless gas with an odor resembling decayed horse radish. [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
RGasD: 2.80

Fl.P: NA (Gas)
UEL: ?
LEL: ?

Flammable Gas
Incompatibilities & Reactivities
Strong oxidizers, acids, water, halogenated hydrocarbons
Measurement Methods
None available
Personal Protection & Sanitation
Skin: Frostbite
Eyes: Frostbite
Wash skin: No recommendation
Remove: When wet (flammable)
Change: No recommendation
Provide: Frostbite
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
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