# 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)
Exposure Limits | 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
See also: INTRODUCTION