Hydraulic Fluids

CAS ID #: 55957-10-3, 68937-40-6; 50815-84-4; 55962-27-1; 66594-31-8

Affected Organ Systems: Dermal (Skin), Gastrointestinal (Digestive), Neurological (Nervous System), Respiratory (From the Nose to the Lungs)

Cancer Classification: None

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Chemical Classification: Hydrocarbons (contain hydrogen and carbon atoms)

Summary: Hydraulic fluids are a large group of liquids made of many kinds of chemicals. They are used in automobile automatic transmissions, brakes, and power steering; fork lift trucks; tractors; bulldozers; industrial machinery; and airplanes. The three most common types of hydraulic fluids are mineral oil, organophosphate ester, and polyalphaolefin. Some of the trade names for hydraulic fluids include Durad®, Fyrquel®, Skydrol®, Houghton-Safe®, Pydraul®, Reofos®, Reolube®, and Quintolubric®. (Use of trade names is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry, the Public Health Service, or the U.S. Department of Health and Human Services.) Some hydraulic fluids have a bland, oily smell and others have no smell; some will burn and some will not burn. Certain hydraulic fluids are produced from crude oil and others are manufactured.