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SULPHUR DIOXIDE

ICSC: 0074

Sulfurous oxide
Sulfurous anhydride
Sulfur oxide
SO2
Molecular mass: 64.1
(cylinder)
ICSC # 0074 		CAS # 7446-09-5
RTECS # WS4550000
UN # 1079
EC # 016-011-00-9
October 10, 2006 Validated

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: cool cylinder by spraying with water but avoid contact of the substance 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.
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.
Safety goggles face shield or eye protection in combination with breathing protection.
First rinse with plenty of water (remove contact lenses if easily possible). Refer for medical attention.
•INGESTION


SPILLAGE DISPOSAL

STORAGE

PACKAGING & LABELLING

Evacuate danger area! Personal protection: complete protective clothing including self-contained breathing apparatus. Consult an expert! Ventilation. NEVER direct water jet on liquid.
Ventilation along the floor. Dry.

Note: 5
T symbol
R: 23-34
S: 1/2-9-26-36/37/39-45
UN Hazard Class: 2.3
UN Subsidiary Risks: 8
Signal: Warning
Cylinder-Skull-Excl mark-Enviro
Contains refrigerated gas; may cause cryogenic burns or injury
Toxic if inhaled
Causes eye irritation
Causes damage to respiratory tract if inhaled
Causes damage to respiratory tract through prolonged or repeated exposure if inhaled
Harmful to aquatic life
ICSC: 0074 Prepared in the context of cooperation between the International Programme on Chemical Safety & the Commission of the European Communities (C) IPCS CEC 1994. No modifications to the International version have been made except to add the OSHA PELs, NIOSH RELs and NIOSH IDLH values.

SULPHUR DIOXIDE

ICSC: 0074

I

M

P

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T

A

N

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D

A

T

A

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).
OSHA PEL†: TWA 5 ppm (13 mg/m3)
NIOSH REL: TWA 2 ppm (5 mg/m3) ST 5 ppm (13 mg/m3)
NIOSH IDLH: 100 ppm See: 7446095


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 the respiratory tract . Inhalation may cause asthma-like reactions.

EFFECTS OF LONG-TERM OR REPEATED EXPOSURE:
Repeated or prolonged inhalation exposure may cause asthma.

PHYSICAL
PROPERTIES

Boiling point: -10°C
Melting point: -75.5°C
Relative density (water = 1): 1.4 at -10°C (liquid)
Solubility in water, ml/100 ml at 25°C: 8.5
Vapour pressure, kPa at 20°C: 330
Relative vapour density (air = 1): 2.25

ENVIRONMENTAL
DATA

The substance is harmful to aquatic organisms.

N O T E S

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.
Transport Emergency Card: TEC (R)-20S1079 or 20G2TC
NFPA Code: H 3; F 0; R 0

ADDITIONAL INFORMATION



ICSC: 0074 SULPHUR DIOXIDE
(C) IPCS, CEC, 1994
IMPORTANT LEGAL NOTICE: Neither NIOSH, the CEC or the IPCS nor any person acting on behalf of NIOSH, the CEC or the IPCS is responsible for the use which might be made of this information. This card contains the collective views of the IPCS Peer Review Committee and may not reflect in all cases all the detailed requirements included in national legislation on the subject. The user should verify compliance of the cards with the relevant legislation in the country of use. The only modifications made to produce the U.S. version is inclusion of the OSHA PELs, NIOSH RELs and NIOSH IDLH values.
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