Compressed dry air (CDA) quality testing to ISO 8573-1
ISO 8573-1 classifies compressed air quality by three groups of contaminants: solid particles, water and oil. Each group has its own class, written together as [A:B:C], for example [1:2:1]. Testing tells you whether the air at the actual point of use meets the specified class.
What we test and the measurement standards
| Contaminant | Why it must be controlled | Measurement standard |
|---|---|---|
| Solid particles (A) | Contaminates parts and products | ISO 8573-4 |
| Water / dew point (B) | Causes pipe corrosion and supports microbial growth | ISO 8573-3 |
| Oil (C) | Contaminates food and medicines | ISO 8573-2 (aerosol) and ISO 8573-5 (vapour) |
What we test in compressed air
The three main contaminant groups in ISO 8573-1
Reading the class under ISO 8573-1:2010
Compressed air quality is written as [A:B:C], where A is the particle class, B the water class and C the oil class. The lower the number, the cleaner the air.
Example [1:2:1]: particle Class 1, pressure dew point ≤ -40 °C (Class 2) and total oil ≤ 0.01 mg/m³ (Class 1)
How we work
1
Identify the points of use and the class required at each point
2
Sample and measure using the methods in the relevant parts of ISO 8573
3
Compare the results with the specified class and issue the report
Frequently asked questions
What is ISO 8573-1?
The international standard that sets purity classes for compressed air based on particles, water and oil.
Where should testing be done?
At the points of use where air contacts the product, not only at the compressor outlet, because contamination can arise in the distribution pipework.
How often should we test?
ISO 8573-1 does not set a fixed interval. Plants set intervals based on risk and customer requirements, and should retest after system changes.
Request a quote
Which class is your compressed air? Tell us the number of points of use and the class you need
