Strainers with higher mesh numbers filter out smaller particles.

• A. True
• B. False
• C. They filter larger particles
• D. They filter all particles equally

Answer: (A)

Mesh size is a measure of how fine a screen is. A higher mesh number means more openings per inch and smaller openings. In filtration, particles larger than the opening get blocked while smaller particles pass through. When the openings are smaller, even smaller particles will be stopped, so a higher mesh screen captures smaller particles than a coarser screen. That’s why a finer mesh is described as filtering out smaller particles. Note that finer screens also slow flow and clog more easily, so practical use requires balancing filtration with flow. The idea that a coarser screen catches smaller particles or that all particles are filtered equally doesn’t fit, because opening size determines which particle sizes are stopped versus passed.