In food, pharma or electronics, compressed air often touches the product directly: bottle blowing, pneumatic conveying, packaging, part cleaning. The slightest trace of oil can contaminate a batch, trigger a recall or fail an audit.

What ISO 8573-1 says

The standard classifies compressed air quality by three contaminants: solid particles, water and oil. Each contaminant gets a class from 0 to 9.

And class 0?

Class 0 is the strictest. Its limits are set by the user or equipment manufacturer, at a level more demanding than class 1 (0.01 mg/m³ of oil). It is the benchmark for applications where air contacts the product.

Two approaches to oil-free air

Filter oil downstream

With a lubricated compressor, coalescing and activated-carbon filters hold back oil. It works, but quality depends on filter maintenance: a saturated or badly fitted element lets oil through.

Remove oil at the source

An oil-free compressor such as the BOGE SO series never puts oil in contact with the compressed air. The bluekat catalytic solution converts oil and hydrocarbons into water and CO₂ for constant class 0 quality.

Often underestimated savings

No oily condensate to treat or dispose of
Fewer filters to replace every year
Less pressure drop, so less energy
Lower risk of non-compliance in audits

Which solution for your site?

For large flows, the SO series (110 to 355 kW) is the benchmark. For small and medium flows, the bluekat series up to 45 kW is very competitive. To upgrade an existing installation, a bluekat converter can be added downstream of your compressors. Our engineers help you compare options over the full lifetime.

Frequently asked questions

Is an oil-free compressor less robust?

No. SO compressors are designed for continuous industrial duty, with planned maintenance like any other compressor.

Is a dryer still needed?

Yes. Oil-free does not mean water-free: a refrigeration or desiccant dryer is still needed depending on the required humidity class.

Oil-free compressed air: understanding class 0