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METHYLAL
ICSC: 1152
Peer-Review Status: 22.04.1994 Validated
Dimethoxymethane
Formal
Formaldehyde dimethylacetal 
CAS #: 109-87-5 RTECS #: PA8750000
UN #: 1234
EINECS #: 203-714-2
    Formula: C3H8O2 / CH2-(OCH3)2
Molecular mass: 76.1

TYPES OF
HAZARD /
EXPOSURE
ACUTE HAZARDS / SYMPTOMS      PREVENTION      FIRST AID / FIRE FIGHTING
FIRE Highly flammable.  NO open flames, NO sparks and NO smoking.  Use water in large amounts, powder, alcohol-resistant foam, carbon dioxide. 
EXPLOSION Vapour/air mixtures are explosive.  Closed system, ventilation, explosion-proof electrical equipment and lighting. Do NOT use compressed air for filling, discharging, or handling.  In case of fire: keep drums, etc., cool by spraying with water. 
 
EXPOSURE      
Inhalation Cough. Dizziness. Drowsiness. Headache. Sore throat. Unconciousness.  Use ventilation, local exhaust or breathing protection.  Fresh air, rest. Refer for medical attention. 
Skin MAY BE ABSORBED! Dry skin. Redness. Pain. Further see Inhalation.  Protective gloves.  Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention . 
Eyes Redness. Pain.  Wear safety spectacles.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion Abdominal pain. Nausea. Vomiting. Further see Inhalation.  Do not eat, drink, or smoke during work.  Rinse mouth. Refer for medical attention . 

SPILLAGE DISPOSAL
PACKAGING & LABELLING
Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. Do NOT wash away into sewer. Personal protection: self-contained breathing apparatus.  Airtight. 
EC Classification
 
UN Classification
UN Hazard Class: 3; UN Pack Group: II 
GHS Classification
 

EMERGENCY RESPONSE SAFE STORAGE
Transport Emergency Card: TEC (R)-30S1234 or 30GF1-I+II.
NFPA Code: H2; F3; R2. 
Fireproof. Separated from strong oxidants. Cool. Keep in the dark. Well closed. Store only if stabilized. 

IMPORTANT DATA
Physical State; Appearance
VERY VOLATILE COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR. 

Physical dangers
The vapour is heavier than air and may travel along the ground; distant ignition possible. 

Chemical dangers
The substance can presumably form explosive peroxides. May explode on heating. Reacts vigorously with strong oxidants. This generates fire and explosion hazard. 

Occupational exposure limits
TLV: 1000ppm as TWA; (ACGIH 2004).
MAK: 1000 ppm, 3200 mg/m³; Peak limitation category: II(2); Pregnancy risk group: D; (DFG 2004). 

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

Inhalation risk
A harmful contamination of the air can be reached rather quickly on evaporation of this substance at 20°C. 

Effects of short-term exposure
The substance is irritating to the eyes, skin and respiratory tract. The substance may cause effects on the central nervous system. Exposure far above the OEL could cause unconsciousness. 

Effects of long-term or repeated exposure
The liquid defats the skin. 


PHYSICAL PROPERTIES ENVIRONMENTAL DATA
Boiling point: 42°C
Melting point: -105°C
Relative density (water = 1): 0.86
Solubility in water, g/100ml at 20°C: 33
Vapour pressure, kPa at 20°C: 44
Relative vapour density (air = 1): 2.6
Relative density of the vapour/air-mixture at 20°C (air = 1): 1.7
Flash point: °C c.c. (o.c.)
Auto-ignition temperature: 237°C
Explosive limits, vol% in air: 1.6-17.6
Octanol/water partition coefficient as log Pow: 0  
 

NOTES
An added stabilizer or inhibitor can influence the toxicological properties of this substance, consult an expert.
Check for peroxides prior to distillation; eliminate if found.
Methylal is metabolized to methanol and formaldehyde and may exhibit the same toxic reactions as these compounds.
See also ICSC0057 Methanol and 0275 Formaldehyde.
Card has been partly updated in April 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