API classification system

Lubricant requirements and specifications. The development of North American classification systems for the SAE began in 1911 on the basis of viscosity alone. In 1947, the API (American Petroleum Institute) developed a performance classification system for engine oils in terms of regular, premium and heavy duty lubricants. By 1952, the API and ASTM (American Society for Testing and Materials) further advanced the system to generally classify engine oils. In 1970, the TRIPARTITE of API, ASTM, and SAE was established to manage a completely new API classification system, see Fig. 2.12 (Haycock, 1993). 

The API classification system is open ended, so that additional classifications can be added when needed. There is a relationship between API engine service classifications and MIL, OEM and ACEA classifications of the oil quality standards previously outlined. These relationships are shown in Table 2,... 

Japanese vehicle manufacturers. In general, they have relied on the API classification system to recommend engine oils for service-fill applications. There is a parallel with Europe (CEC) in the Japanese Automobile Standards Organization JASO they have developed four engine test procedures without giving pass/fail limits. The parallel is not complete because neither within nor outside Japan do the vehicle manufacturers require any of these tests to be run to meet their own specifications. 

Class G and Class H oil well cements are the most important ones in the API classification system, and are the most extensively used for cementing oil and gas wells. They can be tailored to cope with a wide range of well-cementing conditions by the addition of suitable additives to their slurries. 

The Biopharmaceutics Classification System (BCS) is based on aqueous solubility and intestinal permeability of the drug substance. It classifies the API into one of four classes ... 

The Biopharmaceutics Classification System (BCS) was proposed in 1995 by Amidon et aU It is a scientific framework which divides APIs into four groups, according to their solubility and permeability properties. 

For pharmaceutical products containing Biopharmaceutics Classification System Class I (highly soluble, highly permeable) APIs... 

In the API system the least demanding classification for a petrol engine was originally designated SA. The most demanding is, at present, SG. (The S stands for Service... 

Hazardous (classified) locations have traditionally been designated by Class, Division, and Group. Equipment used in areas so designated is selected and systems are designed, based on requirements established for the classification. This approach is defined in Article 500 of the NEC and API 500. 

In Section 4 of API 570 the concept of Piping Service Classes is introduced. The classification was developed to allow extra inspection efforts to be focused on piping systems that may have the highest potential consequences, if failure or loss of containment should occur. 

Similar to motor oils, there are two systems of classification SAE with regard to viscosity and API with regard to operational properties. 

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