Compressor Terminology: What are some commonly Used Acronyms

Sometimes in the world of compressors the lingo can be confusing. Unless you are totally immersed in the compressor industry, some of the terminology might be completely lost on you. 

Let's have a look at some commonly used acronymns in the compressed air world:

PSI – Pounds per square inch: A unit of pressure commonly used to measure the operating pressure of compressors.

CFM – Cubic Feet per Minute: A unit measurement used to express the volumetric flow rate of air or gas.

SCFM – Standard Cubic Feet per Minute: similar to CFM, but it represents the volumetric flow rate of air or gas at standard conditions.

VSD – Variable Speed Drive: A technology that allows the speed of the compressor motor to be adjusted, resulting in energy savings and improved efficiency.

HP – Horsepower: A unit of power used to quantify the output or capacity of a compressor motor.

RPM – Revolutions per Minute: A measure of the rotational speed of a compressor’s motor of compressor pump.

FAD – Free Air Delivery – the volume flow rate of gas compressed and delivered at the standard discharge point, referred to the atmospheric conditions of the site, not affected by the compressor.

RH – Relative Humidity – the typical relative humidity for ambient air is around 60-80%. It is defined as the ratio between the water content to the amount of water the air can possibly hold at the same temperature.

DP – Dew Point – can be described as the temperature at which dew/condensation occurs.

PDP - Pressure Dew Point – describes the water content in the air at actual pressure.

ADP - Atmospheric Dew Point – Describes the water content at the ambient pressure. Some customers who expand their air back to atmospheric pressure at the point of use and then use it in their process are interested in this value.

These are just some of the acronyms are commonly used in the compressor industry, and understanding their meanings can help you be better equipped to engage in discussions, make informed decisions, and appreciate the critical role that compressors play in various industries.

Do you have an idea for our #expertcorner?Β Let us know!

Useful links:

Book your Service here

Browse our Services here

Browse our Products here

Browse our News corner here

Browse our Sustainability focus here



Who we are and how Ash Air can help your business!

Ash Air has been around in New Zealand since 1979, and we’ve grown into a nationwide company with international support and a reputation for quality and reliability.We look after all things compressed air for your business!

  • Rotary Screw and Piston Air Compressors
  • Vacuum Pumps and Blowers
  • Nitrogen Generation
  • An extensive line of Air Treatment components
  • AIRnet Piping System and  Filtration
  • Mobile Compressors, Generators, and Light Towers

Ash Air's range of Chicago Pneumatic, ALUP, Pneumatech, and Atlas Copco products are used extensively around the world in industries ranging from oil and gas to food, automotive and farming, and we bring you these world-class compressors here in the land of the long white cloud.Our technicians are compressed air equipment experts and are dedicated to addressing customer needs. Supported with nationwide coverage, Ash Air offers one of the widest selections of compressed air, vacuum pump, and industrial gas equipment and parts available today in New Zealand.

Reliability and Efficiency

With Ash Air, you can count on reliability and high performance for even the most demanding applications. We focus our efforts on the following:

  • Increasing uptime
  • Reducing unexpected repairs
  • Reducing energy consumption and meeting our sustainability goals
  • Improving the cleanliness of compressed air


Talk to the team today:  CONTACT US CONTACT US

Read more from our #expertcorner


A liquid ring vacuum pump is a powerful and steadfast piece of equipment that, if well maintained, can provide years of dependable performance. Whether you purchase a large or small unit, you can rely on a vacuum pump for smooth, consistent and relatively quiet operation for many months on end between each inspection. …


Just like any other equipment, a compressed air installation also requires the necessary maintenance work during its entire lifespan. Even though maintenance costs are only about 5 to 10% of a machine's annual operating costs, failure to budget for maintenance can have potentially disastrous consequences. …


The air dyer is one of the most ignored cooler in the system. A dirty condenser will cause water in the lines, or worse it will cause complete dryer failure. …


Using nitrogen is not about fully replacing CO2, but it can reduce their consumption of CO2 by close to 70%. Using nitrogen is about sustainability. Creating your own nitrogen is easy and will reduce the use of a greenhouse gas, which is better for the environment. It will also save you money as early as month one adding that savings to your bottom line. …

Show More