One of the most important factors in the world of microbial air sampling is the sample rate. In simple terms, the sample rate refers to how quickly an air sampler gathers a specific volume of air for testing — different air sampling methods are recommended for different purposes.
Because there are a myriad of uses for air sampling, it’s vital to understand which air sampling rate is best for your workspace needs.
High Sampling Rates
High air sampling rates are generally considered to be between 50-100 LPM. Sampling at a high rate is recommended when the goal is collecting a large volume of air, such as a cubic meter, in a short period of time. High sampling rates work well for shorter processing or testing events, non-process or routine facility monitoring of ISO 7 – ISO 9 areas such as production support zones, labs, and bulk production spaces.
Low Sampling Rates
Microbial air sampling at a lower rate, commonly at 28.3 LPM, or 1 CFM, has its own benefits. This air sampling method is desirable for extended sampling periods when continuous monitoring for the entire product exposure window is required. Low sampling rates are ideal for ISO 5 – ISO 6 environments such as fill lines, sterility champers, BFS, biological safety cabinets, Laminar flow hoods, and barrier isolators. Any event that needs to be tested for longer than 30 minutes and up to a day or more should probably rely on low sampling rates. The longer the sampling period, the fewer times personnel are required to enter the critical area to collect and replace test plates. And, it is well known, that personnel are the number one source of contaminants in a clean room environment!
Exact recommendations for air sampling rates depend heavily on your specific needs and the environment in which you work. If you need assistance in sorting out which air sampling setup would be best for your environment, or simply have questions about our air samplers and their many options, please contact us at 877.850.4244 or visit www.emtekair.com for more information.