By: Alexandra I.
School: Turtle Rock Elementary
Science Teacher: Sumer Dakak
To prevent COVID-19, the Center of Disease Control (CDC) asks everyone to wear a facemask in public. There are thousands of brands of reusable and disposable non-medical facemasks currently on the market. A cheap, home-made device was constructed to compare filtering efficiency of different brands of facemasks. This device includes a vacuum cleaner, several layers of filters, and a printer toner where toner particles are similar in size (1-10 micron) to airborne (0.5 – 5 micron) and respiratory (5 – 15 micron) droplets that transmit COVID-19. In this study, disposable brands of facemasks removed micron-sized particles better than tested reusable brands of facemasks. The difference was significant. Despite superior efficiency of disposable facemasks, they are less popular than reusable facemasks. Observations of general public in Compton and Irvine showed that reusable facemasks were used more often than disposable. Alexandra’s device and data can help people to find the brand of facemasks that best serves their needs.
Analysis and Results
Surprisingly, there is a significant difference in the efficiency of different facemasks. N95 respirators removed all particles, while the polyester-based reusable masks were marginally efficient. The data demonstrates that disposable facemasks filter micron-sized particles better than the reusable facemasks.
Alexandra’s data correlates with recently published data from Florida University (Verma 2020) and Virginia Tech University (Pan 2020) that recommend a three-layer mask consisting of outer layers of a flexible, tightly woven fabric and an inner layer consisting of a material designed to filter out particles. The student’s experiments were done earlier than those publications. Further, she compared popular brands that are sold and used by many people. Alexandra suggests a simple, cheap, and easy way to build device that anyone can use to test any brand of facemasks at home. Information about the most efficient facemasks educates us about the best choices.