Too often during compressed air leak audits, high pressure compressed air personnel cleaning stations are discovered. Use of high pressure compressed air blowing (above 30 psi) is common in plants with dusty environments where workers’ clothing may become soiled. Blow nozzles with safety tips — and pressure regulators used to reduce pressure — are very often replaced or bypassed by unknowing workers.
Worse still is when compressed air is used in horseplay; in extreme cases, this can lead to fatalities when compressed air enters the body through various orifices or through the skin. (Even a cursory Google search for “compressed air death” will quickly lead to horrifying stories from all over the world; so this is truly a caude for concern.) Another risk is flying debris caused by high velocity compressed air flow — it can enter the eyes or become imbedded in a person’s skin.
For this reason, in many jurisdictions the use of compressed air for cleaning is illegal. There are quite a few low pressure solutions out there, one of which uses blower power as shown in Figure 1, a cleaning station found in a local wood products plant.
Cleaning with low pressure can also save on power costs. This cleaning station consumes about 1 kW of power when operating. A similar compressed air powered nozzle consuming 20 cfm of high pressure compressed air would use the equivalent of 4 kW of compressed air power.
You should check out your cleaning methods in your plant to ensure you are within regulations, and prepare to save energy as icing on the cake.
More information about cleaning safety can be found here.
Ron Marshall is a compressed air energy expert and owner of Marshall Compressed Air Consulting (www.compressedairaudit.com)