Compressed Air Best Practices Magazine and Trace Analytics LLC clear confusion on compressed air testing within the manufacturing industry in this comprehensive article. Compressed air is used in more than 70 percent of all manufacturing activities, and when compressed air is used in the production of pharmaceuticals, food, beverages, medical devices, and other products, there seems to be confusion on what testing needs to be performed.
Compressed Air & Gas Institute (CAGI) cites 10 contaminants that fall within 4 categories:
- Particles (from pipe scale, wear particles and atmospheric dirt)
- Water (liquid, vapor and aerosol)
- Oil (liquid, vapor and aerosol)
The international standard ISO 8573-1:2010 is a compressed air quality specification that addresses these very same specific contaminants by providing a range of purity classes for particles, water, and oil. It does not include classes for gases or microorganisms.
Employing a Standard for Compressed Air Testing
ISO 8573 consists of 9 parts in which ISO 8573-1 is most frequently cited. Parts 2 through 9 provide analytical techniques and sampling methods. Many air compressor and filter manufacturers cite ISO 8573-1:2010 purity classes to describe the quality of air that can be produced with their products.
The summary chart below shows purity classes 0 through X for particles, water, and oil. The end user can then select a purity class for each contaminant based on either equipment installed or air quality required for a specific process or product. The contaminants and limits that need to be tested are defined by the compressor system filtration and point-of-use filters that were selected for your manufacturing facility and product line.