Product Information



Ortho-phosphoric acid; White phosphoric acid.




Chemical Formula



Molecular Weight




    Physical & Chemical Properties



Clear, colorless syrupy liquid.






Miscible in all proportions in water.

Boiling Point


158°C (316°F)

Melting Point


42°C (107°F)

Vapor Pressure (mm Hg)


0.03 @ 20°C (68°F)

Specific Gravity


1.69 @ 25°C



1.5 (0.1 N aqueous solution)

% Volatiles by volume @ 21°C(70°F)



Vapor Density (Air=1)





It is used in cleaning operations to remove encrusted surface matter and mineral scale found on metal equipment  such as boilers and steam producing equipment. It is also used to brighten metals and remove rust.


   Safety & First aid

Inhalation is not an expected hazard unless misted or heated to high temperatures. Mist or vapor inhalation can cause irritation to the nose, throat, and upper respiratory tract. Severe exposures can lead to a chemical pneumonitis.

Corrosive. May cause sore throat, abdominal pain, nausea, and severe burns
of the mouth, throat, and stomach. Severe exposures can lead to shock, circulatory collapse, and death.

Skin Contact:
Corrosive. May cause redness, pain, and severe skin burns.

Eye Contact:
Corrosive. May cause redness, pain, blurred vision, eye burns, and permanent eye damage.

Aggravation of Pre-existing Conditions:
Persons with pre-existing skin disorders or eye problems, or impaired respiratory function may be more susceptible to the effects of the substance.


First Aid

Remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Call a physician immediately.

If swallowed, DO NOT INDUCE VOMITING. Give large quantities of water. Never give anything by mouth to an unconscious person. Get medical attention immediately.

Skin Contact:
Immediately flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes. Call a physician, immediately.
Wash clothing before reuse.

Eye Contact:
Immediately flush eyes with gentle but large stream of water for at least 15 minutes, lifting lower and upper eyelids occasionally. Call a physician immediately.

Fire Fighting Measures

Not considered to be a fire hazard. Contact with most metals causes formation of flammable and explosive hydrogen gas.

Not considered to be an explosion hazard.

Fire Extinguishing Media:
Use any means suitable for extinguishing surrounding fire. Water spray may be used to keep fire exposed containers cool. If water is used, use in abundance to control heat and acid build-up.

Special Information:
In the event of a fire, wear full protective clothing and self-contained breathing apparatus with full facepiece operated in the pressure demand or other positive pressure mode.

    Special Features


Incompatible Materials:
Water and water vapor. In water, reacts violently.

Hazardous Decomposition Products:
Hydrochloric and phosphoric acid upon hydrolysis.

Hazardous Polymerization:
Will not occur.