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HYDROGEN SULFIDEICSC: 0165
April 2017
CAS #: 7783-06-4Dihydrogen sulphide
Hydrogen sulphide
UN #: 1053
EINECS #: 231-977-3

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Extremely flammable.  Gas/air mixtures are explosive.  NO open flames, NO sparks and NO smoking.  Closed system, ventilation, explosion-proof electrical equipment and lighting. Prevent build-up of electrostatic charges (e.g., by grounding) if in liquid state. Do NOT use compressed air for filling, discharging, or handling.  Shut off supply; if not possible and no risk to surroundings, let the fire burn itself out. In other cases extinguish with water spray, dry powder.  In case of fire: keep cylinder cool by spraying with water. 

 AVOID ALL CONTACT! IN ALL CASES CONSULT A DOCTOR! 
  SYMPTOMS ACUTE HAZARDS FIRST AID
Inhalation Cough. Headache. Dizziness. Nausea. Laboured breathing. Shortness of breath. Irregular heartbeat. Convulsions. Unconsciousness.  Use ventilation, local exhaust or breathing protection.  Administration of oxygen may be needed. Fresh air, rest. Half-upright position. Artificial respiration may be needed. No mouth-to-mouth artificial respiration. Refer immediately 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 or eye protection in combination with breathing protection.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion   Do not eat, drink, or smoke during work.   

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Remove all ignition sources. Evacuate danger area! Consult an expert! Personal protection: gas-tight chemical protection suit including self-contained breathing apparatus. Do NOT let this chemical enter the environment. Shut off cylinder if possible. Ventilation. Remove gas with fine water spray. Isolate the area until the gas has dispersed. 

According to UN GHS Criteria

flam;flamecylinder;gasskull;toxicenviro;aqua
DANGER
Extremely flammable gas
Contains gas under pressure; may explode if heated
Fatal if inhaled
Causes serious eye irritation
May cause respiratory irritation
Very toxic to aquatic life 

Transportation
UN Classification
UN Hazard Class: 2.3; UN Subsidiary Risks: 2.1 

STORAGE
Fireproof. Separated from strong oxidants. Cool. Keep in a well-ventilated room. Install continous monitoring system with alarm. Provision to contain effluent from fire extinguishing. Store in an area without drain or sewer access. 
PACKAGING
 
HYDROGEN SULFIDE ICSC: 0165
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
COLOURLESS COMPRESSED LIQUEFIED GAS WITH CHARACTERISTIC ODOUR OF ROTTEN EGGS. 

Physical dangers
The gas is heavier than air and may travel along the ground; distant ignition possible. As a result of flow, agitation, etc., electrostatic charges can be generated. 

Chemical dangers
Heating may cause violent combustion or explosion. Decomposes on burning. This produces toxic gases of sulfur oxides. Reacts with strong oxidants. This generates fire and explosion hazard. Attacks many metals and some plastics. 

Formula: H2S
Molecular mass: 34.1
Boiling point: -60°C
Melting point: -85°C
Solubility in water, g/100ml at 20°C: 0.5
Relative vapour density (air = 1): 1.19
Flash point: Flammable gas
Auto-ignition temperature: 270°C
Explosive limits, vol% in air: 3.9-45.5
Vapour pressure, kPa at 20°C: 1880
Relative density (water = 1): 0.92  


EXPOSURE & HEALTH EFFECTS

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

Effects of short-term exposure
Rapid evaporation of the liquid may cause frostbite. The substance is irritating to the eyes and respiratory tract. Inhalation of this gas may cause lung oedema. The effects may be delayed. Medical observation is indicated. See Notes. The substance may cause effects on the central nervous system. Exposure could cause unconsciousness. Exposure could cause death. 

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
 


Occupational exposure limits
TLV: 1 ppm as TWA; 5 ppm as STEL.
MAK: 7.1 mg/m3, 5 ppm; peak limitation category: I(2); pregnancy risk group: C.
EU-OEL: 7 mg/m3, 5 ppm as TWA; 14 mg/m3, 10 ppm as STEL 

ENVIRONMENT
The substance is very toxic to aquatic organisms. 

NOTES
The symptoms of lung oedema 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.
Specific treatment is necessary in case of poisoning with this substance; the appropriate means with instructions must be available.
Since the warning effect of the odour may be absent above the OEL (paralysis of the olfactory nerve), there is considerable risk of intoxication. The odour cannot be relied on as an adequate warning of the presence of hydrogen sulfide. 

ADDITIONAL INFORMATION
  EC Classification
Symbol: F+, T+, N; R: 12-26-50; S: (1/2)-9-16-36-38-45-61 

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    See Also:
       Toxicological Abbreviations
       Hydrogen sulfide (EHC 19, 1981)