ASTM stands for American Society of Testing and Materials which provide a standard globally accepted method of calling or recognizing the physical properties of rubber products that are used in the automotive applications. The most common material classification system is used in O rings. The ASTM D 2000 standard classification system helps in understanding the physical properties of these elastomeric seals so that a proper seal can be chosen based on the environment it has to be used in.

ASTM D 2000 specification helps in designating “Line Call-Out” for rubber and elastomer seals. Considering an example, suppose this is the way specification is written

ASTM-D2000-99 M 2 HK 7 14 A1-10, B38, C12, EF31, EO88, F15, Z1

So here, ASTM-D2000-99 represents the year in which the ASTM D 2000 specification has been revised. In this example, the revision year is 2000 to which line call out makes reference.

“M” alphabet refers to measurement unit which can be either represent temperature in degree Celsius or tensile strength in MPa and tear strength in kN/m. In case if this “M” alphabet is not present in the elastomeric seal specification, it means that the units to be considered for Temperature will be Degree F, Tensile strength will be Psi and tear strength will be ppi.

“2” represents Grade number. It designates that more extensive tests are required. In case if it is “1”, this grade number means that the seal has basic properties.

“HK” represents Type and Class as per below table

“7” represents hardness and “14” represents tensile strength.

“A1-10, B38, C12, EF31, EO88, F15, Z1” represents test requirements as per below table