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Selenium

Synonyms & Trade Names
Elemental selenium, Selenium alloy
CAS No.
7782-49-2
RTECS No.
DOT ID & Guide
2658 152(powder)
Formula
Se
Conversion
IDLH
1 mg/m3 (as Se)
See: 7782492
Exposure Limits
NIOSH REL
TWA 0.2 mg/m3 [*Note: The REL also applies to other selenium compounds (as Se) except Selenium hexafluoride.]
OSHA PEL
TWA 0.2 mg/m3 [*Note: The PEL also applies to other selenium compounds (as Se) except Selenium hexafluoride.]
Measurement Methods
NIOSH S190 (II-7) , 7300 , 7301 , 7303 , 9102;
OSHA ID121
See: NMAM or OSHA Methods
Physical Description
Amorphous or crystalline, red to gray solid. [Note: Occurs as an impurity in most sulfide ores.]
Molecular Weight
79.0
Boiling Point
1265°F
Melting Point
392°F
Solubility
Insoluble
Vapor Pressure
0 mmHg (approx)
Ionization Potential
NA
Specific Gravity
4.28
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Combustible Solid
Incompatibilities & Reactivities
Acids, strong oxidizers, chromium trioxide, potassium bromate, cadmium
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, nose, throat; visual disturbance; headache; chills, fever; dyspnea (breathing difficulty), bronchitis; metallic taste, garlic breath, gastrointestinal disturbance; dermatitis; eye, skin burns; In Animals: anemia; liver necrosis, cirrhosis; kidney, spleen damage
Target Organs
Eyes, skin, respiratory system, liver, kidneys, blood, spleen
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:No recommendation
Wash skin:When contaminated
Remove:When wet or contaminated
Change:No recommendation
Provide:Quick drench
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH/OSHA

Up to 1 mg/m3:
(APF = 5) Any quarter-mask respirator.
Click here for information on selection of N, R, or P filters.*
(APF = 10) Any particulate respirator equipped with an N95, R95, or P95 filter (including N95, R95, and P95 filtering facepieces) except quarter-mask respirators. The following filters may also be used: N99, R99, P99, N100, R100, P100.
Click here for information on selection of N, R, or P filters.*/


(APF = 50) Any air-purifying, full-facepiece respirator with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters. 


(APF = 25) Any powered, air-purifying respirator with a high-efficiency particulate filter.*
(APF = 25) Any powered, air-purifying respirator with a high-efficiency particulate filter.*
(APF = 10) Any supplied-air respirator*
(APF = 50) Any self-contained breathing apparatus 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 with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters. 


Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0072
Page last reviewed: October 30, 2019