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METHYL CHLORIDE
ICSC: 0419
Peer-Review Status: 25.03.1999 Validated
Chloromethane
Monochloromethane 
CAS #: 74-87-3 RTECS #: PA6300000
UN #: 1063
EC #: 602-001-00-7
EINECS #: 200-817-4
    Formula: CH3Cl
Molecular mass: 50.5

TYPES OF
HAZARD /
EXPOSURE
ACUTE HAZARDS / SYMPTOMS      PREVENTION      FIRST AID / FIRE FIGHTING
FIRE Highly flammable. Heating will cause rise in pressure with risk of bursting.  NO open flames, NO sparks and NO smoking.  Shut off supply; if not possible and no risk to surroundings, let the fire burn itself out. In other cases extinguish with water spray. 
EXPLOSION Gas/air mixtures are explosive.  Closed system, ventilation, explosion-proof electrical equipment and lighting. Use non-sparking handtools.  In case of fire: keep cylinder cool by spraying with water. Combat fire from a sheltered position. 
 
EXPOSURE   STRICT HYGIENE!   
Inhalation Staggering gait. Dizziness. Headache. Nausea. Vomiting. Convulsions. Unconciousness. 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. 
Eyes See Skin.  Wear safety goggles, face shield or eye protection in combination with breathing protection.   
Ingestion      

SPILLAGE DISPOSAL
PACKAGING & LABELLING
Evacuate danger area! Consult an expert! Personal protection: complete protective clothing including self-contained breathing apparatus. Ventilation. NEVER direct water jet on liquid.   
EC Classification
Symbol: F+, Xn; R: 12-40-48/20; S: (2)-9-16-33 
UN Classification
UN Hazard Class: 2.1 
GHS Classification
 

EMERGENCY RESPONSE SAFE STORAGE
Transport Emergency Card: TEC (R)-20S1063 or 20G2F.
NFPA Code: H2; F4; R0. 
Fireproof. Ventilation along the floor. 

IMPORTANT DATA
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. 

Occupational exposure limits
TLV: 50 ppm as TWA; 100 ppm as STEL; (skin); A4 (not classifiable as a human carcinogen); (ACGIH 2004).
MAK: 50 ppm, 100 mg/m³; Carcinogen category: 3B; Peak limitation category: II(2); Pregnancy risk group: B; Skin absorption (H); (DFG 2004). 

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

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

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. 

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. 


PHYSICAL PROPERTIES ENVIRONMENTAL DATA
Boiling point: -24.2°C
Melting point: -97.6°C
Relative density (water = 1): 0.92
Solubility in water, g/100ml at 25°C: 0.5
Vapour pressure, kPa at 21°C: 506
Relative vapour density (air = 1): 1.8
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  
 

NOTES
Following intoxication patient should be observed carefully for 48 hours.
Check oxygen content before entering area.
Card has been partly updated in October 2005.
See sections Occupational Exposure Limits, Emergency Response. 

ADDITIONAL INFORMATION
 

IPCS
International
Programme on
Chemical Safety
WHO ILO EC Prepared in the context of cooperation between the International Programme on Chemical Safety and the European Commission
© IPCS 2004-2012
LEGAL NOTICE Neither the EC nor the IPCS nor any person acting on behalf of the EC or the IPCS is responsible for the use which might be made of this information.
    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)