The Importance of Masks
It is evident that the virus is spread via aerosols that can remain airborne for up to 8 minutes.
A recent research study by a biomedical imaging expert, showed that different materials used in masks have an impact on their effectiveness of reducing the spread of the novel coronavirus that causes COVID-19. Significantly, bandanas, scarves or face coverings made with single layer breathable fabrics perform WORSE than no mask at all!
Masks with air-vents are NOT recommended. Air vents allow particles or aerosols to escape.
1. N99 Masks
The N99 masks were the most effective at reducing the risk of infection by 99% for 30-second exposure periods and 94% for 20-minute exposure windows.
The ethical consideration of reserving these masks for health workers and their high costs are a factor in public distribution.
2. N95 Masks
N95 masks, surgical masks and masks with pockets to insert vacuum filters were the next best performers with 83% prevention rates over a 30-second period and 58% prevention rates over 20-minute periods.
3. Multi-Layer Masks
Researchers found that multi-layer masks were the next best bet and tested a variety of fabric used to make these masks including cotton-blend fabrics, tea-towel fabrics and antimicrobial pillowcase fabrics.
The more layers the better the protection.
4. Single-Layer Masks
Single-layer masks, scarves, bandanas and cotton t-shirts reduced the risk of infection by 44% after 30-seconds and only 24% after 20-minute exposure windows, only slighter better than wearing no mask at all.
5. Bandanas and very light fabrics
A study by an expert in biomedical imaging demonstrated that very light fabric coverings actually break up exhaled droplets, forming smaller droplets and aerosols, which stay airborne for longer and are therefore WORSE than no facial covering at all.