Difference Between ISO, ANSI, DIN, and ASTM Standards

What is Difference Between ISO, ANSI, DIN, and ASTM

ISO (International Organization for Standardization): ISO is a non-government organization that develops and publishes international standards. ISO standards are widely used in many industries, including fasteners, and are recognized globally.

ASTM (American Society for Testing and Materials): ASTM is a non-profit organization that develops and publishes technical standards for a wide range of materials, products, systems, and services, including fasteners. ASTM standards are primarily used in the United States, but are also recognized globally.

ANSI (American National Standards Institute): ANSI is a non-profit organization that accredits and coordinates the development of voluntary standards in the United States. ANSI is the official U.S. representative to the ISO and is responsible for ensuring that U.S. standards are consistent with international standards.

DIN (Deutsches Institut für Normung): DIN is a German standards organization that develops and publishes technical standards, including standards for fasteners. DIN standards are primarily used in Germany and in other countries in Europe, but are also recognized globally.

Difference Between ANSI and DIN

DIN is most commonly specified in European countries, while ANSI is usually specified in the United States. Therefore, the majority of factories in North America are likely to have piping that is ANSI certified, while similar plants in European countries have DIN piping. When working with piping that uses the ANSI standard, the flange bolt patterns, face-to-face valve dimensions and pressure requirements will all be in standard measurements (inches and psi). DIN standards use metric measurements (mm and bar) to measure the valve and flange sizes and pressures.

ANSI vs DIN chart

In general, US-based companies, such as those in the automotive and food industries, choose to work with ANSI, especially if manufacturing is done in the United States. European firms typically employ DIN, even if manufacturing occurs in the United States.