1. n. [General Terms]
Abbreviation for American Petroleum Institute, a trade association founded in 1919 with offices in Washington, DC, USA. The API is sponsored by the oil and gas industry and is recognized worldwide. Among its long-term endeavors is the development of standardized testing procedures for drilling equipment, drilling fluids and cements, called API Recommended Practices ("RPs"). The API licenses the use of its monogram (logo), monitors supplier quality assurance methods and sets minimum standards for materials used in drilling and completion operations, called API Specifications ("Specs"). The API works in conjunction with the International Organization of Standards (ISO).

Note: "API Publications, Programs and Services Catalogue" can be ordered from the API in electronic form at: http://www.api.org.

Recommended Practice on the Rheology and Hydraulics of Oil-Well Drilling Fluids, 3rd ed. Washington, DC, USA: American Petroleum Institute, 1995.
Recommended Practice Standard Procedure for Laboratory Testing of Drilling Fluids, 5th ed. Washington, DC, USA: American Petroleum Institute, 1995.