With Covid-19 cases rising rapidly across the country, including here in Pima County, it is a good time to reconsider your mask choice. N95’s and surgical masks offer the best protection. N95’s block 95-99% of particles. However, not everyone has access to them. Lindsey Marr, Professor of Civil and Environmental Engineering at Virginia Tech recently tested 11 different mask materials. While a simple cloth mask is better than nothing at all, improvements to your mask or a change to another material can reduce your chances of getting or spreading the virus.
In the Virginia Tech study, 100% cotton masks provided about 50% filtration. They tested other materials including vacuum cleaner bags, coffee filters, bandanas, face shields, and surgical masks. Based on their study analyzing inward and outward protection, the researchers recommend a three-layer mask consisting of two outer layers consisting of flexible, tightly woven fabric and an inner layer designed to filter out smaller particles. For the inner layer, they recommend a MERV 14 filter, vacuum bag, or good surgical mask. Test the materials for yourself because comfort and breathability are critically important.
In their research, they offer several other conclusions. Regarding acrylic face shields, they do not recommend using them as a single defense against Covid-19. They offer almost no protection against airborne particles. A face shield should only be used in conjunction with a mask.
Tie strings generally work better than ear loops for most people. This is because tie strings will generally make the mask fit tighter against your face than ear loops.
Mask fit is an essential factor in reducing the spread of the virus. A mask material that blocks 80% of particles blocks far less than that in reality if there are gaps between the mask and your face. Make sure that there are no holes or space between the mask and your face.
The Virginia Tech research included an analysis of inward and outward protection of all mask materials. It is widely believed that a mask essentially protects others from you (i.e. outward protection). They found that while the amount of protection is less, a mask also protects the wearer from those around him or her. For example, the outward protection filtration efficiency might be 75% while the inward filtration efficiency is 50%.
At SYNERGY HomeCare of Tucson, we are extremely focused on the safety of our caregivers and our home care clients. We offer surgical masks and KN95’s to all caregivers, as well as surgical gloves and hand sanitizer. We also make PPE available to our clients.