Food, pharmaceuticals, electronics, laboratories, paint shops, any process where compressed air touches what you make. ISO 8573-1 grades air at the point of use on three contaminants: particles, water, oil. Class 0 is not one more step on the scale: it is a content agreed between supplier and user, stricter than class 1, and verified by measurement.
In practice the trade has settled it: class 0 means an oil-free machine, and that is what a specification expects when it writes it. A lubricated screw followed by activated-carbon filtration and an adsorption dryer answers a requirement for oil-free air, never a document that writes class 0.
The scroll, a contact-free spiral, covers small flows quietly: 2.2 to 45 kW, 0.24 to 4.96 m³/min. The rotary tooth takes over from 15 to 55 kW. The water-injected oil-free screw runs from 5.5 to 220 kW for 0.78 to 39.5 m³/min; the dry screw from 45 to 250 kW for 7.8 to 46 m³/min. Beyond that, the centrifugal turbo delivers 48 to 3,000 m³/min.
The house order of preference runs from the simplest to the most complex: scroll, rotary tooth, lubricated screw with treatment where the specification allows it, dry screw last. Oil-free boosters, from 8 to 40 bar, raise the pressure of a network that is already clean.
The same two figures as everywhere, flow in m³/min and pressure in bar, plus one requirement: the target air class for the three contaminants, written as “ISO 8573-1 class 1-2-1” for instance. It decides the drying and the filtration as much as the compressor.
Oil-free does not mean water-free: compressed air carries vapour whatever the machine. A dryer is still needed, refrigerated for a +3 °C dew point, adsorption for -40 °C or -70 °C.
The rules of the lubricated screw apply here: every bar too many costs about 7%, an unloaded machine still draws 15 to 35% of its power, and a permanent-magnet drive removes those idle hours on a fluctuating load. Oil-free screws and scrolls exist in variable speed in the catalogue.
Specific power is read on each model page: measured flow, motor power, noise level. Compare two machines at the same pressure, never on brochure figures.
A dryer, particle filtration, and for food and pharma a sterile filter at the point of use. The receiver and the condensate drains are the same as in lubricated. Every model page computes these on the machine's flow.
Not in the standard's sense: ISO 8573-1 leaves the class 0 content to be agreed between supplier and user, stricter than class 1. Yes in the trade's sense: a specification that writes class 0 expects an oil-free machine, and that is how CEZIUM reads it.
Flow decides. Up to 4.96 m³/min, the scroll is the simplest and the quietest. Beyond, the water-injected oil-free screw from 0.78 to 39.5 m³/min, then the dry screw up to 46 m³/min.
Three years of machine warranty, extended to five years as long as the installation stays supervised by SEENTINEL; if supervision stops, the warranty returns to three years. Parts available for ten years after delivery, shipped within 24 to 48 hours in mainland France.
