Compressed air purity testing verifies that the air delivered to the process meets the required ISO 8573-1 class. It measures the three contaminant groups, particles, water and oil, using dedicated instruments at the point of use.
What is measured
- Particle size and concentration with a particle counter
- Pressure dew point with a hygrometer or dew-point sensor
- Oil content with an oil aerosol analyser or chemical detector
How testing is done
Sampling is performed at the point of use, because the air quality at the compressor outlet is not the same as at the tool. The measurements are compared with the target class, and the results documented for quality records or audits.
Why test regularly
Filters and dryers degrade over time, and a single test does not guarantee future performance. Regular testing, or continuous monitoring on critical systems, catches degradation before it contaminates the product or process.