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METHYL CHLORIDEICSC: 0419
June 2015
CAS #: 74-87-3Chloromethane
Monochloromethane
UN #: 1063
EINECS #: 200-817-4

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Highly flammable. Heating will cause rise in pressure with risk of bursting.  Gas/air mixtures are explosive.  NO open flames, NO sparks and NO smoking.  Closed system, ventilation, explosion-proof electrical equipment and lighting. 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.  In case of fire: keep cylinder cool by spraying with water. Combat fire from a sheltered position. 

 STRICT HYGIENE!  
  SYMPTOMS ACUTE HAZARDS FIRST AID
Inhalation Staggering gait. Dizziness. Headache. Nausea. Vomiting. Convulsions. Unconsciousness. See Notes.  Use ventilation, local exhaust or breathing protection.  Fresh air, rest. Artificial respiration may be needed. Refer for medical attention. 
Skin MAY BE ABSORBED! ON CONTACT WITH LIQUID: FROSTBITE.  Cold-insulating gloves. Protective clothing.  ON FROSTBITE: rinse with plenty of water, do NOT remove clothes. Refer for medical attention . 
Eyes See Skin.  Wear safety goggles, face shield or eye protection in combination with breathing protection.   
Ingestion      

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Evacuate danger area! Consult an expert! Personal protection: complete protective clothing including self-contained breathing apparatus. Ventilation. NEVER direct water jet on liquid. 

According to UN GHS Criteria

flam;flamecylinder;gascancer;health haz
DANGER
Extremely flammable gas
Contains gas under pressure; may explode if heated
Suspected of damaging fertility or the unborn child
May cause damage to central nervous system if inhaled
May cause damage to central nervous system through prolonged or repeated exposure if inhaled 

Transportation
UN Classification
UN Hazard Class: 2.1 

STORAGE
Fireproof. Ventilation along the floor. 
PACKAGING
 
METHYL CHLORIDE ICSC: 0419
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
COLOURLESS LIQUEFIED GAS. 

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. See Notes. 

Chemical dangers
Decomposes on burning. This produces toxic and corrosive fumes including hydrogen chloride and phosgene. Reacts violently with powdered aluminium, powdered zinc, aluminium trichloride and ethylene. This generates fire and explosion hazard. Attacks many metals in the presence of moisture. 

Formula: CH3Cl
Molecular mass: 50.5
Boiling point: -23.7°C
Melting point: -97°C
Relative density (water = 1): 0.91
Solubility in water, g/100ml at 25°C: 0.5
Vapour pressure, kPa at 25°C: 573
Relative vapour density (air = 1): 2.47
Flash point: Flammable gas
Auto-ignition temperature: 632°C
Explosive limits, vol% in air: 8.1-17.4
Octanol/water partition coefficient as log Pow: 0.91
Viscosity: 0.1834 cP at 20°C 


EXPOSURE & HEALTH EFFECTS

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

Effects of short-term exposure
The liquid may cause frostbite. The substance may cause effects on the central nervous system. Exposure far above the OEL could cause liver, cardiovascular system and kidney damage. Exposure could cause unconsciousness. Medical observation is indicated. The effects may be delayed. 

Inhalation risk
A harmful concentration of this gas in the air will be reached very quickly on loss of containment. 

Effects of long-term or repeated exposure
The substance may have effects on the central nervous system. This may result in effects measured using behavioural tests. Animal tests show that this substance possibly causes toxic effects upon human reproduction. 


Occupational exposure limits
TLV: 50 ppm as TWA; 100 ppm as STEL; (skin); A4 (not classifiable as a human carcinogen).
MAK: 100 mg/m3, 50 ppm; peak limitation category: II(2); skin absorption (H); carcinogen category: 3B; pregnancy risk group: B 

ENVIRONMENT
 

NOTES
Following intoxication patient should be observed carefully for 48 hours.
Check oxygen content before entering the area. 

ADDITIONAL INFORMATION
  EC Classification
Symbol: F+, Xn; R: 12-40-48/20; S: (2)-9-16-33 

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    See Also:
       Toxicological Abbreviations
       Methyl chloride (WHO Food Additives Series 14)
       Methyl chloride (PIM 339)
       Methyl chloride (CICADS 28, 2001)
       Methyl Chloride (IARC Summary & Evaluation, Volume 71, 1999)