ISO 8573-1 And Air Compressor Hire

We’ve posted before about oil free air and water in air, these, along with solid particles are covered by an ISO standard for containments in compressed air, ISO 8573.

The standard is divided into nine different parts 8573-2 through to 9 outline testing methods to determine classification but it is 8573-1 which we will be looking at here. This standard provides an easy to understand class system to describe the purity of compressed air and allow users to specify the appropriate purity levels for their application.

How Does The ISO 8573-1 Standard Work?

The ISO 8573-1 standard categorizes contaminants into three groups: solid particulates, water (liquid and vapour), and oil (aerosols and vapour). Each group has multiple purity classifications, and it’s important to note that the lower the number, the purer the air needs to be. The levels of each containment allowable for each classification is detailed in a single table below.

When specifying the purity of air required, the standard must always be referenced, followed by the purity class selected for each contaminant (a different purity class can be selected for each contaminant if required). An example a purity or class of air would be ISO 8573-1 Class 1.2.1. It is often the case that it will be specified simply as “class 121”. The three numbers 121 refer to solid particulate, water and total oil in that order. We can see by referencing the table that the air required for this application breaks down as follows:

Class 1 Particulate In each cubic metre of compressed air, the particulate count should not exceed 20,000 particles in the 0.1 – 0.5 micron size range, 400 particles in the 0.5 – 1 micron size range and 10 particles in the 1 – 5 micron size range.

Class 2 Water A pressure dew-point (PDP) of -40°C or better is required and no liquid water is allowed.

Class 1 Oil In each cubic metre of compressed air, not more than 0.01mg of oil is allowed. This is a total level for liquid oil, oil aerosol and oil vapour.

Class Zero Air

You can see from the table that class zero, for any of the categories, is air that exceeds the purity of class 1. It is important to understand that in this context it refers to the air produced by the compressed air system as a whole, not one component part. For example we have designed and built our own oil free air compressors that are certified class zero for oil contamination which would be a natural choice for an application such as a pharmaceutical facility with a requirement for air more pure than specified in class 1 but the actual written specification of the application requirement still needs to be considered along with the system as a whole.

Supplying A Rental Solution For Your Application

At GenAir we understand what the ISO standard is, how to apply it and what equipment – whether that’s oil free compressors, dryers, filtration systems or a combination of all of those things – is required to produce the classification of air you require at the pressure and in the quantity you need it. If you’re looking to hire air compressors to cover routine maintenance on a clean air system or need a temporary system to deliver air for a project we will be able to supply the equipment you need.