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  • Peg Minichiello

How to Conduct Microbial Testing

Compressed air used in organizations must be monitored regularly in accordance with national and international standards. The International Organization for Standardization (ISO) has a list of standards that industries must adhere to. These standards ensure that products are of the highest quality and safe too.

There are different methods you can pick from to test the presence of pollutants in the environment you’re operating your compressed air systems in. Generally, the method you use must involve accurately measuring and sampling a specific volume of air for microbial burden analysis.

Follow these quick easy steps.

Picking Equipment for Testing

The first step is to decide on the equipment that you’re going to use for testing. You have the option of using small portable samplers or robust pieces of equipment depending on the size of your organization.

Whichever method you use, it’s important that the operator reads the manual to establish the product’s limitations.

You’ll Need Two Blinds and a Sterility Bank

After deciding on the sampler you’re going to use, the next step is to ensure you have two blinds and a sterility bank. Note that these requirements are in accordance with the ISO 8573-7.

Blinds are to ensure that there aren’t any foreign contaminants that will enter the air sampler. The second control required is the sterility bank which is used to transport the sample from the manufacturer to the place of sampling.

Take a Compressed Air Sample

Now that you have the sampler and control plates in place, you need to collect the air sample. Fortunately, the process is quite easy:

  • A sterile tube is used to sample the outlet air which is passed through a manifold.

  • This manifold works by measuring the air through the calibrated flow meter and pressure gauge.

  • When the flow rate is established, the pressure gauge is closed.

Antiseptic Technique is IMPORTANT

It’s important that the entire procedure is free of contaminants to prevent an incorrect result. Making use of the antiseptic technique is one way of preventing outside contamination. Here you have to ensure that you wear the right protective gear and also disinfect the area.

Interpret the Report

The final step is to understand the results but know that what is discussed here is actually a continuous process. Continuous monitoring and retesting will be necessary because contamination can occur at any point. According to the ISO, you must conduct microbial testing at least quarterly or bi-annually.

Need Help Testing?

Need some help with microbial testing? CDA Systems’ expertise in clean dry air will assure the proper solution for your process. You only need to contact us on 925.667.3400/ and we’ll be at your service.

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