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SILICONICSC: 1508 (November 2003)
CAS #: 7440-21-3
UN #: 1346
EC Number: 231-130-8

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Combustible under specific conditions.  Finely dispersed particles form explosive mixtures in air. Risk of fire and explosion on contact with halogens or oxidizing agents.  NO open flames.  Closed system, dust explosion-proof electrical equipment and lighting. Prevent deposition of dust. Prevent build-up of electrostatic charges (e.g., by grounding).  Use special powder, dry sand. NO hydrous agents.   

   
  SYMPTOMS PREVENTION FIRST AID
Inhalation Cough.  Use local exhaust or breathing protection.  Fresh air, rest. 
Skin Redness. Roughness.  Protective gloves.  Rinse skin with plenty of water or shower. 
Eyes Redness.  Wear safety goggles.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion   Do not eat, drink, or smoke during work.  Rinse mouth. 

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Sweep spilled substance into covered containers. If appropriate, moisten first to prevent dusting. 

According to UN GHS Criteria

 

Transportation
UN Classification
UN Hazard Class: 4.1; UN Pack Group: III 

STORAGE
Separated from incompatible materials. See Chemical Dangers. 
PACKAGING
 
SILICON ICSC: 1508
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
STEEL-GREY CRYSTALS OR BLACK-TO-BROWN AMORPHOUS POWDER. 

Physical dangers
Dust explosion possible if in powder or granular form, mixed with air. If dry, it can be charged electrostatically by swirling, pneumatic transport, pouring, etc. 

Chemical dangers
Reacts violently with oxidants, halogens, metal carbonates and metal acetylides. This generates fire hazard. Reacts violently with metal hexafluorides. This generates fire and explosion hazard. Reacts on heating with water. This produces flammable/explosive gas (hydrogen - see ICSC 0001). 

Formula: Si
Atomic mass: 28.09
Boiling point: 2355°C
Melting point: 1410°C
Density: 2.33 g/cm³
Solubility in water: none 


EXPOSURE & HEALTH EFFECTS

Routes of exposure
The substance can be absorbed into the body by inhalation. 

Effects of short-term exposure
May cause mechanical irritation to the eyes and respiratory tract. 

Inhalation risk
A nuisance-causing concentration of airborne particles can be reached quickly when dispersed. 

Effects of long-term or repeated exposure
 


OCCUPATIONAL EXPOSURE LIMITS
 

ENVIRONMENT
 

NOTES
Reacts violently with fire extinguishing agents such as water. 

ADDITIONAL INFORMATION
  EC Classification
 

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    See Also:
       Toxicological Abbreviations