Festo Guide to Air Compressor Regulators – Clean Compressed Air

May 2020


Why are Air Compressor Regulators Important?

One cubic metre of compressed air generated contains millions of dirt particles, considerable amounts of water and oil, and even heavy metals like lead, cadmium and mercury. If they are not filtered out, trouble-free operation of the system components cannot be guaranteed in the long term.

Also, these harmful substances substantially reduce product quality. As a result, the right compressed air preparation is essential for reducing machine downtime and idle periods, and for guaranteeing process and product reliability.

Those are good reasons for you to pay attention to the quality of your compressed air!

Poorly prepared compressed air causes faults such as:

  • Accelerated seal wear
  • Contaminated control valves
  • Oil-fouled silencers



Possible effects for the user and the machine:

  • Low machine availability
  • Higher energy costs due to leakages
  • Higher maintenance costs
  • Shorter component and system service life

The right compressed air preparation systems significantly increase the long service life of Festo components and systems – as well as the process and product reliability.

Compressed air quality to ISO 8573-1:2010

ISO 8573 is the name for a group of international standards for the quality – or purity – of compressed air. It represents the quality requirements for compressed air and specifies the maximum amount of contaminants that can be present in the respective classes.

This standard has been binding for automation using pneumatics since 2010. To ensure that compressed air preparation complies with the standard and is energy efficient, various parameters must be observed.

What quality of compressed air do you require?

Check which products from the FESTO MS series for air preparation will fit your system.

Compressed Air Preparation for Clean solution

This standard has been binding for automation using pneumatics since 2010. To ensure that compressed air preparation complies with the standard and is energy efficient, various parameters must be observed.


You should clarify the following questions in advance:

  • How high is the maximum flow rate required?
  • Do all consumers require the same compressed air quality?
  • What compressed air quality is provided by the compressor?


A perfect match for many industries.

Many industries have strict requirements for compressed air quality. While the priorities for the food and packaging industries are food safety and problem-free consumption, PWIS-free compressed air is essential in paint shops. Festo service units and filters guarantee excellent functionality.

Some examples:


1. For direct contact with “non-dry” foods (e.g. drinks, meat, vegetables etc.)

The compressed air is used for transporting or mixing, or in general food production. It thus comes into direct contact with the food.


2. In packaging machines

If compressed air comes into direct contact with packaging materials for food, the packaging material is considered part of the food sector.

The following classifications apply for both applications: ISO 8573-1:2010

Particles = Class 1
Water = Class 4
Oil = Class 1


3. For direct contact with dry foods

The compressed air is used for transporting or mixing, or in general food production. Therefore, it comes into direct contact with the food. Increased requirements apply in this case since air humidity plays an important role.

As a result, the following compressed air quality classifications in accordance with ISO 8573-1:2010 are recommended in these applications:

Particles = Class 1
Water = Class 2
Oil = Class 1

Compliance with the compressed air quality classes specified here is of great importance to guarantee maximum safety for the food and protect the health of the consumer.


4. Clear view: visual displace- ment encoders in machine tools (ISO 8573-1:2010 Class 1:4:1)

Visual displacement encoders

e.g. in milling or machine tools require cleaning air with air quality class 1:4:1 in accordance with ISO 8573-1:2010 for a long service life. The high-purity compressed air is routed inside, preventing ingress of impure ambient air into the housing. That also means that oil mist cannot wet and damage the glassscale – a key requirement for a long service life of the displacement encoder. The filter combination for this: 5 + 1 + 0.01 μm + activated carbon filter

The impressive FESTO MS and D series – pressure regulators for every requirement

From a simple standard product through to application-specific solutions with the very strictest requirements for compressed air quality, Festo’s product range makes it easy to find solutions that meet your needs exactly. Every product is based on decades of expertise and a keen eye for future requirements.

Expertise meets innovation!

The service units from the D series – in metal or polymer designs – and the MS series are ideal for standard tasks. The MS series performs the other tasks, up to the high-end range, finely scaled with the right functions for the required ISO class. Also integrated: diagnostic functions for higher machine availability. Or the safety solutions to
ISO 13849-1.

The almost unlimited options of the FESTO MS series

From highly sensitive applications in the pharmaceutical or food industry to application-specific solutions with sturdy flow performance for the automotive industry, the service units from the MS series are used almost anywhere, either centrally or decentrally.

  • For standard applications and application-specific solutions
  • Optimum product range with the most modern functionality
  • Modular connection system for rapid assembly and dismantling
  • 4 sizes with highest flow rates with low dimensions

The almost unlimited options of the FESTO MS series

The D series is available in sturdy metal for standard applications and basic logic functions for decentralized preparation. Or in the attractively priced polymer variant DB for reliable and economical compressed air preparation in uncritical environments. This is ideal for moving machine components, where low weight is required, for example.

  • Reliable compressed air preparation for applications in uncritical environments
  • Freely combinable within the D series from Festo
  • One size with G¼ connection.

How can our Specialty Division PAC: Process, Automation & Controls help you with your FESTO needs?

E.B. Horsman’s dedicated PAC division has a close partnership with FESTO to ensure the team is fully equipped to assist with sizing and selecting the right components for your air preparation needs. We also lend application support with start-up and troubleshooting. Combining our full line of process, automation, controls & motion products with expert technical consulting to support your industrial needs. Contact us today for your FESTO needs:

  • Specifications and design support
  • Product Selection Recommendations
  • Quotation
  • Inventory Support & Supply Management
  • Delivery Logistics
  • Training
  • Post-Sale Technical Support

FESTO Manufacturer Spotlight

Festo is a leading global manufacturer of pneumatic and electromechanical systems, components, and controls, ensuring safety and

Food & Beverage Electrical Solutions

Learn about E.B. Horsman’s expertise and wide range of electrical, automation, instrumentation, and lighting supplies for the food and beverage industry. Read

Achieving Electrical Safety By Design – LittelFuse

This white paper discusses implementing the higher levels of the hierarchy of controls, moving beyond Personal Protective Equipment (PPE) and reducing both the risk and incidence of electrical hazards and components that can be designed into an electrical