What standard typically specifies the cleanliness code in lubrication?

The ISO standards, particularly ISO 4406, are integral in specifying cleanliness codes for lubricants and hydraulic fluids. Cleanliness codes provide a standard method for expressing the levels of particulate contamination in these fluids, allowing for consistent measurement and communication across industries. This standard helps ensure that the lubricants used in machinery meet specific cleanliness requirements, which is crucial for preventing wear and extending the life of equipment.

ISO standards are recognized globally and facilitate international trade and safety by establishing clear guidelines. They also cover a wide range of applications, enhancing compatibility and reliability in lubrication practices.

In contrast, the other standards mentioned have different focuses: SAE (Society of Automotive Engineers) standards mainly relate to automotive engineering and vehicle design, ASTM (American Society for Testing and Materials) standards tend to address material specifications and testing methods, while API (American Petroleum Institute) standards focus primarily on oil and gas industry practices, including performance and quality standards for petroleum products. Hence, ISO standards specifically highlight the cleanliness code in lubrication, making it the right choice in this context.