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PHOSPHORIC ACIDICSC: 1008 (November 2016)
Orthophosphoric acid
CAS #: 7664-38-2
UN #: 3453
EC Number: 231-633-2

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Not combustible. Gives off irritating or toxic fumes (or gases) in a fire.  Risk of fire and explosion on contact with incompatible substances. See Chemical Dangers.    NO contact with incompatible materials: See Chemical Dangers  In case of fire in the surroundings, use appropriate extinguishing media.  In case of fire: keep drums, etc., cool by spraying with water. NO direct contact of the substance with water. 

 AVOID ALL CONTACT! IN ALL CASES CONSULT A DOCTOR! 
  SYMPTOMS PREVENTION FIRST AID
Inhalation Cough. Sore throat. Burning sensation. Shortness of breath. Laboured breathing.  Use ventilation, local exhaust or breathing protection.  Fresh air, rest. Half-upright position. Artificial respiration may be needed. Refer immediately for medical attention. 
Skin Redness. Pain. Blisters. Serious skin burns.  Protective gloves. Protective clothing.  Wear protective gloves when administering first aid. Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer immediately for medical attention . 
Eyes Redness. Pain. Severe burns.  Wear 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 immediately for medical attention. 
Ingestion Burns in mouth and throat. Burning sensation behind the breastbone. Abdominal pain. Vomiting. Shock or collapse.  Do not eat, drink, or smoke during work.  Rinse mouth. Give nothing to drink. Do NOT induce vomiting. Refer immediately for medical attention. 

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Sweep spilled substance into covered containers. Carefully collect remainder. Then wash away with plenty of water. Then store and dispose of according to local regulations. 

According to UN GHS Criteria

correxcl mark;warn
DANGER
May be corrosive to metals
Causes severe skin burns and eye damage
May cause respiratory irritation
See Notes 

Transportation
UN Classification
UN Hazard Class: 8; UN Pack Group: III 

STORAGE
Dry. Well closed. Separated from food and feedstuffs and incompatible materials. See Chemical Dangers. Ventilation along the floor. 
PACKAGING
Do not transport with food and feedstuffs. 
PHOSPHORIC ACID ICSC: 1008
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
HYGROSCOPIC COLOURLESS CRYSTALS. 

Physical dangers
 

Chemical dangers
The substance is a medium strong acid. Reacts violently with bases. The substance violently polymerizes under the influence of azo compounds and epoxides. On combustion, forms toxic fumes of phosphorus oxides. Decomposes on contact with alcohols, aldehydes, cyanides, ketones, phenols, esters, sulfides or halogenated organics. This produces toxic fumes. Attacks many metals. This produces flammable/explosive gas (hydrogen - see ICSC 0001). 

Formula: H3O4P / H3PO4
Molecular mass: 98.0
Decomposes at 213°C
Melting point: 42°C
Density: 1.9 g/cm³
Solubility in water: miscible
Vapour pressure, Pa at 25°C: <10 (negligible)
Relative vapour density (air = 1): 3.4  


EXPOSURE & HEALTH EFFECTS

Routes of exposure
Serious local effects by all routes of exposure. 

Effects of short-term exposure
The substance is corrosive to the eyes, skin and respiratory tract. Corrosive on ingestion. Inhalation may cause asthma-like reactions (RADS). Exposure could cause asphyxiation due to swelling in the throat. Inhalation of high concentrations may cause lung oedema, but only after initial corrosive effects on the eyes and the upper respiratory tract have become manifest. Inhalation of high concentrations may cause pneumonitis. See Notes. 

Inhalation risk
A harmful contamination of the air will not or will only very slowly be reached on evaporation of this substance at 20°C. 

Effects of long-term or repeated exposure
The substance may have effects on the upper respiratory tract and lungs. This may result in chronic inflammation and reduced lung function . Mists of this strong inorganic acid are carcinogenic to humans. See Notes. 


OCCUPATIONAL EXPOSURE LIMITS
TLV: 1 mg/m3, as TWA; 3 mg/m3 as STEL.
MAK: (inhalable fraction): 2 mg/m3; peak limitation category: I(2); pregnancy risk group: C.
EU-OEL: 1 mg/m3 as TWA; 2 mg/m3 as STEL 

ENVIRONMENT
 

NOTES
UN number 1805 is used for phosphoric acid solutions.
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.
IARC considers mists of strong inorganic acid to be carcinogenic (group 1). However there is no information available on the carcinogenicity of other physical forms of this substance. Therefore no classification for carcinogenicity under GHS has been applied.
NEVER pour water into this substance; when dissolving or diluting always add it slowly to the water. 

ADDITIONAL INFORMATION
  EC Classification
Symbol: C; R: 34; S: (1/2)-26-45; Note: B 

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    See Also:
       Toxicological Abbreviations
       Phosphoric acid (FAO Nutrition Meetings Report Series 38a)
       PHOSPHORIC ACID (JECFA Evaluation)
       Phosphoric acid (UKPID)