Selenium

Synonyms & Trade Names

Elemental selenium, Selenium alloy

CAS No.

7782-49-2

RTECS No.

VS7700000

DOT ID & Guide

2658 152(powder)

Formula

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

Specific Gravity

4.28

Flash Point

Upper Explosive Limit

Lower Explosive Limit

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

Selenium

NIOSH REL

OSHA PEL

Follow NIOSH

NIOSH Homepage