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ISOBUTENEICSC: 1027
April 2000
CAS #: 115-11-7Isobutylene
2-Methylpropene
1,1-Dimethylethylene
UN #: 1055
EINECS #: 204-066-3

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Extremely flammable.  Gas/air mixtures are explosive. Risk of fire and explosion on contact with oxidizing agents or halogens. See Chemical Dangers.  NO open flames, NO sparks and NO smoking. NO contact with oxidizing agents.  Closed system, ventilation, explosion-proof electrical equipment and lighting. Prevent build-up of electrostatic charges (e.g., by grounding). Use non-sparking handtools.  Shut off supply; if not possible and no risk to surroundings, let the fire burn itself out. In other cases extinguish with water spray, powder, carbon dioxide.  In case of fire: keep drums, etc., cool by spraying with water. Combat fire from a sheltered position. 

   
  SYMPTOMS ACUTE HAZARDS FIRST AID
Inhalation Dizziness. Drowsiness. Lethargy. Nausea. Unconsciousness. Vomiting.  Use closed system or ventilation.  Fresh air, rest. Artificial respiration may be needed. Refer for medical attention. 
Skin ON CONTACT WITH LIQUID: FROSTBITE.  Cold-insulating gloves.  ON FROSTBITE: rinse with plenty of water, do NOT remove clothes. Refer for medical attention . 
Eyes See Skin.  Wear face shield or eye protection in combination with breathing protection.  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.   

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Evacuate danger area! Consult an expert! Ventilation. Remove all ignition sources. Do NOT wash away into sewer. NEVER direct water jet on liquid. Personal protection: chemical protection suit including self-contained breathing apparatus. 

According to UN GHS Criteria

 

Transportation
UN Classification
UN Hazard Class: 2.1 

STORAGE
Fireproof. Separated from incompatible materials. See Chemical Dangers. Cool. 
PACKAGING
 
ISOBUTENE ICSC: 1027
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
COLOURLESS COMPRESSED LIQUEFIED GAS WITH CHARACTERISTIC ODOUR. 

Physical dangers
The gas is heavier than air and may travel along the ground; distant ignition possible. The gas is heavier than air and may accumulate in lowered spaces causing a deficiency of oxygen. As a result of flow, agitation, etc., electrostatic charges can be generated. 

Chemical dangers
Reacts violently with halogens, oxidants and strong acids. This generates fire and explosion hazard. 

Formula: C4H8 / CH2=C(CH3)2
Molecular mass: 56.1
Boiling point: -6.9°C
Melting point: -140.3°C
Relative density (water = 1): 0.59
Solubility in water, g/100ml at 20°C: 0.03
Vapour pressure, kPa at 20°C: 257
Relative vapour density (air = 1): 1.94
Flash point: -76.1°C c.c.
Auto-ignition temperature: 465°C
Explosive limits, vol% in air: 1.8-9.6
Octanol/water partition coefficient as log Pow: 2.35  


EXPOSURE & HEALTH EFFECTS

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

Effects of short-term exposure
Rapid evaporation of the liquid may cause frostbite. The substance may cause effects on the central nervous system. Exposure at high levels could cause unconsciousness. 

Inhalation risk
On loss of containment this substance can cause serious risk of suffocation when in confined areas. 

Effects of long-term or repeated exposure
 


Occupational exposure limits
TLV: 250 ppm as TWA; A4 (not classifiable as a human carcinogen) 

ENVIRONMENT
 

NOTES
Density of the liquid at boiling point: 0.605 kg/l.
High concentrations in the air cause a deficiency of oxygen with the risk of unconsciousness or death.
Check oxygen content before entering area.
Turn leaking cylinder with the leak up to prevent escape of gas in liquid state. 

ADDITIONAL INFORMATION
  EC Classification
Symbol: F+; R: 12; S: (2)-9-16-33; Note: C 

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    See Also:
       Toxicological Abbreviations