1991 ISO 8573-1: classes 1-5

The 1991 ISO 8573-1 edition of the air quality standard established five purity classes, 1 through 5. The best, Class 1, specified an oil concentration of ≤ 0.01 mg/m3 at 1 bar(a) and 20°C. Conformance to Class 1 was sometimes called “a technically oil-free solution”.

However, only oil aerosols and liquids were considered. Below 35°C, vapors could be ignored when, in fact, the quantity of vapors may be higher than aerosols. Some manufacturers still use this old edition to promote their machines.

Published date: 2008-11-01 09:00