Which device is most commonly used for viable air sampling?

• A. Filter cassette
• B. Most common device for viable air sampling
• C. Gas sampling pump
• D. Liquid impinger

Answer: (B)

The key idea is preserving live organisms while you collect them from the air so they can be cultured later. A liquid impinger is designed to pull air through a liquid, trapping microorganisms directly in that liquid. This keeps them hydrated and minimizes damage, which helps maintain viability for subsequent plating or other culture-based analyses. Because preserving viability is central to viable sampling, the liquid impinger approach is the most commonly used method, making it the best fit among the options. In contrast, dry collection on a filter can stress or kill organisms, and a gas pump is intended for gases rather than bioaerosols.