Compressed air that contacts food in any way must be free of contaminants. Contaminants include water vapor, moisture, solid particulates (including spores), oil aerosols and vapors. Two basic types of air compressors are used in a food facility:
Oil-injected compressors are less expensive and require less maintenance. They also tend to tolerate warmer and cooler operating environments better. Food-grade lubricants must be used with these compressors.
A refrigerated air dryer will reduce the compressed air dew point to approximately 36 °F by cooling the air and condensing the water vapor. It is not possible to achieve dew points below freezing with a refrigerated air dryer.
A filter should be installed at the point of use for each compressed air line. This filter will remove any remaining water that may have accumulated in the line, as well as any oil or other contaminates. Our team understands the various filtration products and associated maximum micron ratings that may be necessary for the removal of solid particles, oil (coalescing filters) and oil vapors (activated carbon filters).
When compressed air enters a food prep, production, packaging, or storage area—but does not meet food directly—it is considered non-contact, yet high-risk. This situation occurs with processes such as blow molding, where air is used to create packaging prior to filling (or in blow-off applications in bakeries to remove dust from equipment). Compressed air is also used in sanitation system for the creation of foam at cleanup stations.