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SULPHUR DIOXIDE
(cylinder)
ICSC: 0074
Peer-Review Status: 10.10.2006 Validated
Sulfurous oxide
Sulfurous anhydride
Sulfur oxide 
CAS #: 7446-09-5 RTECS #: WS4550000
UN #: 1079
EC #: 016-011-00-9
EINECS #: 231-195-2
    Formula: SO2
Molecular mass: 64.1

TYPES OF
HAZARD /
EXPOSURE
ACUTE HAZARDS / SYMPTOMS      PREVENTION      FIRST AID / FIRE FIGHTING
FIRE Not combustible. Heating will cause rise in pressure with risk of bursting.    In case of fire in the surroundings, use appropriate extinguishing media. 
EXPLOSION     In case of fire: keep cylinder cool by spraying with water. NO direct contact with water. Combat fire from a sheltered position. 
 
EXPOSURE   STRICT HYGIENE!  IN ALL CASES CONSULT A DOCTOR! 
Inhalation Cough. Shortness of breath. Sore throat. Laboured breathing. See Notes.  Use ventilation, local exhaust or breathing protection.  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 Redness. Pain.  Wear safety goggles, face shield or eye protection in combination with breathing protection.  Rinse with plenty of water for several minutes (remove contact lenses if easily possible). Refer for medical attention. 
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.  Note: 5 
EC Classification
Symbol: T; R: 23-34; S: (1/2)-9-26-36/37/39-45 
UN Classification
UN Hazard Class: 2.3; UN Subsidiary Risks: 8 
GHS Classification
Signal: Warning
Contains refrigerated gas; may cause cryogenic burns or injury
Toxic if inhaled
Causes eye irritation
Causes damage to respiratory tract if if inhaled
Causes damage to respiratory tract through prolonged or repeated exposure if if inhaled
Harmful to aquatic life 
cylinder;gasskull;toxicexcl mark;warnenviro;aqua

EMERGENCY RESPONSE SAFE STORAGE
Transport Emergency Card: TEC (R)-20S1079 or 20G2TC.
NFPA Code: H3; F0; R0. 
Ventilation along the floor. Dry. 

IMPORTANT DATA
Physical State; Appearance
COLOURLESS GAS OR COMPRESSED LIQUEFIED GAS WITH PUNGENT ODOUR. 

Physical dangers
The gas is heavier than air. 

Chemical dangers
The solution in water is a medium strong acid. Reacts violently with sodium hydride. Attacks plastic. 

Occupational exposure limits
TLV: 2 ppm as TWA; 5 ppm as STEL; A4 (not classifiable as a human carcinogen); (ACGIH 2006).
MAK: 0.5 ppm, 1.3 mg/m³; Peak limitation category: I(1); Pregnancy risk group: C; (DFG 2006). 

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

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
Rapid evaporation of the liquid may cause frostbite. The substance is irritating to the eyes and respiratory tract. Inhalation may cause asthma-like reactions. The substance may cause effects on the respiratory tract. This may result in asthma-like reactions, reflex spasm of the larynx and respiratory arrest. The effects may be delayed. Medical observation is indicated. 

Effects of long-term or repeated exposure
Repeated or prolonged inhalation may cause asthma. 


PHYSICAL PROPERTIES ENVIRONMENTAL DATA
Boiling point: -10°C
Melting point: -75.5°C
Relative density (water = 1): 1.4 (liquid, -10°C)
Solubility in water, ml/100ml at 25°C: 8.5
Vapour pressure, kPa at 20°C: 330
Relative vapour density (air = 1): 2.25  
The substance is harmful to aquatic organisms. 

NOTES
Depending on the degree of exposure, periodic medical examination is suggested.
The symptoms of asthma often do not become manifest until a few hours have passed and they are aggravated by physical effort.
Rest and medical observation are therefore essential.
Anyone who has shown symptoms of asthma due to this substance should avoid all further contact.
Do NOT spray water on leaking cylinder (to prevent corrosion of cylinder).
Turn leaking cylinder with the leak up to prevent escape of gas in liquid state. 

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