Compressed Air Quality in the Meat Industry

Reliably monitor the dew point, residual oil, and particles—where hygiene, product safety, and audit compliance are critical.

Compressed air is a critical operating medium in the meat industry. It can come into direct contact with unpackaged meat or influence processes involving the product. What matters most is not only how the air is treated in the compressor room, but also its actual quality at the point of use.

Three parameters are particularly relevant for assessing compressed air quality: pressure dew point, residual oil, and particles. The measurement location and monitoring logic vary depending on the specific application.

Dew point: Measure centrally after treatment

The pressure dew point is an important parameter for the hygienic evaluation of compressed air, since humidity can promote the growth of microorganisms. The growth of microorganisms in compressed air slows as the pressure dew point decreases and comes to a halt below -26 °C (BCAS R102-1). For this reason, a Class 2 pressure dew point of -40 °C is often targeted.

Residual oil: Monitor centrally before condensation forms

The residual oil content should also be monitored centrally after treatment. The reason: The air is significantly warmer after the compressor than in the distribution network and in the production areas. In meat processing, temperatures are often around 10 °C, and in cold storage rooms, they are significantly lower.
This increases the risk that gaseous oil components will condense in the cooler network and accumulate there. This is precisely what must be prevented, as it can lead to oil carryover. Centralized residual oil measurement is therefore an essential component of ensuring hygienically safe compressed air.

Particles: Measure at the sampling point

Particles must be evaluated differently than dew point and residual oil. They may originate not only from the generation process but also arise within the distribution network itself—for example, due to corrosion, abrasion, or filter issues. For this reason, the measurement of particles at the point of use is particularly meaningful.
Thus, the purity in the compressor room does not automatically correspond to the purity at the consumer. For a reliable assessment, the actual conditions must be taken into account where the compressed air is used in the process.

Audit and Verification: Risk-Based and by Withdrawal Point

At the latest during an audit, compressed air quality becomes a subject that must be assessed. Current standards require a risk-based approach to process media. For compressed air that comes into direct contact with food or primary packaging, the following applies: It must not pose a contamination risk and must be monitored.
It is important to note that the standards generally do not specify blanket numerical values but require a justified determination for each extraction point. In practice, this results in: 

• a complete register of all extraction points,
• an assessment of the type of contact,
• the specified purity class,
• a testing plan specifying the point of measurement, method, and frequency,
• as well as a defined procedure for handling deviations.

This ensures that compressed air quality is not only technically controlled but also documented in a manner that is audit-ready.

Contamination: Where It Can Occur

Compressed air can become contaminated as early as the intake stage or pick up contaminants during compression, treatment, storage, and distribution. The most significant contaminants are particles, water, oil, and microorganisms.

It is particularly important to note that the quality of the compressed air in the compressor room is not automatically the same as the quality at the point of use. Pipes, storage tanks, filters, hoses, and points of use can subsequently alter the air quality in the system. Therefore, compressed air must be evaluated at the point where it actually performs its function in the process.

Relevant Sources and Standards

The following norms and standards are particularly relevant to compressed air quality in the meat industry:

  • ISO 8573-1:2010 - Purity classes for compressed air
  • ISO 8573-2 through -9 - Test methods for humidity, oil, particles, free water, and microbiological contaminants
  • VDMA Standard Sheet 15390-2:2018 – Application Guidelines for Compressed Air Purity in the Food and Pharmaceutical Industries
  • IFS Food Version 8 - Requirements for process media and compressed air in direct contact with food or primary packaging
  • BRCGS Food Safety Issue 9 - Monitoring of Compressed Air in Direct Contact with Products at the Point of Use
  • SQF Food Safety Code Edition 10 - Risk-Based Monitoring of Clean Compressed Air
  • FSSC 22000 version 6 / ISO/TS 22002-1 - Requirements for utility media and the assessment of compressed air applications
  • Regulation (EC) No. 852/2004 - Food Hygiene
  • Commission Communication 2022/C 355/01 - Guidelines on HACCP Principles

Conclusion

Compressed air quality in the meat industry is a matter of hygiene, process control, and compliance all at once. Three factors are crucial: centrally monitoring the dew point and residual oil content after treatment, checking for particles at the point of use, and clearly documenting the requirements for each application. In this way, compressed air becomes a controlled component of the hygienic process chain.