Compressed Gas Sampling- Particle Velocity
A big question we get about air sampling compressed air is how to perform it appropriately. First, it is crucial to ensure that the gasses used in your manufacturing processes are not contaminating your product. Two factors you need to control when monitoring compressed gasses, velocity, and volume. Ensuring these you managed these two factors, you will acquire the desired result from sampling.
First, let’s explain particle velocity, monitoring for viable and non-viable particles; the particle velocity can impact your sample in different ways. The non-viable particle counters use an electrical response to calculate particle size; this is a function of flow and area to get a controlled velocity. If particles flow much faster through the sensor, they will read a much smaller particle size than the particle. The quicker speed will cause the undesired result of having larger particles in your compressed gas, and you are unaware. For the viable particle counter, the impact velocity of your particle to your media is your primary concern. Higher speeds may kill your organism upon impact to your agar plate, hence not having the desired recovery from your monitoring.
The problems generated from velocity cause the worst-case scenario, not finding the contamination in the source and finding it later in your product testing. This contamination will cause two undesired situations: the waste of your product and the cost of the investigation to determine where the contamination is occurring in your process. These problems come with a price that labs can significantly avoid.