There is just one problem: Ambient air always contains some (or many) contaminants.
As a result, compressed air is under constant assault from tiny particles, moisture and oil.
Keeping them out, e.g. with oil-free compressors, dryers, water separators and filters, is not just good business, in many cases it is also required to meet air quality standards.
Compliance with air quality and compressor regulations
Compressed air equipment, as well as the air it produces, is subject to national and international standards and recommendations.
In terms of air quality, the most important of them is ISO 8573-1:2010. This international standard for air purity classes defines the acceptable level of moisture, particulate, oil and other pollutants in a compressed air stream.
There are lots of applications for which purity is of little importance. For example, when it comes to operating a jackhammer, the only reason why you have to pay attention to keeping contaminants out of the compressed air is to protect the tool and the system itself.
There are many others, however, in which purity is very important, especially when the compressed air comes into contact with end products that are later consumed, such as food or pharmaceuticals.
As a rule of thumb, you can broadly categorize air into four groups: Breathing air, such as that used in hospitals, has to be the purest. Next is process air, which is the air that comes into contact with end products. Then you have instrument air, which is used for pneumatic equipment, valves and electrical controls. Finally, there is plant air, which is needed for applications such as air drying and doesn’t have to be clean at all.
In addition to the air itself, you should also find out what standards and regulations the compressed air equipment in your country or industry is subject to.
In the EU, for example, compressors have to comply with a variety of general machinery, electrical safety, noise and environmental standards as well as those governing pressure equipment.
