Contact us

NSF Public Health Tip: Choosing a Mask

Public health organization NSF recommends using the “Three Fs” – Fit, Fiber and Flow – when deciding on a mask to help prevent the spread of COVID-19 and other infectious diseases.
Choosing the best face mask

ANN ARBOR, Mich. – NSF is helping consumers choose the most suitable face mask to help prevent the spread of infectious diseases like COVID-19. Do your part - use the “Three Fs” to choose the best mask for you:

  • FIT: Masks should fit snugly and cover your mouth and nose, with no gaps or openings. If you feel air coming in from the sides/top/bottom when you breathe, adjust the fit to close the gaps.
  • FIBER: Natural fibers like cotton or wool have rougher threads and are better than paper or synthetics at trapping water droplets that carry disease. Look for masks with at least two layers; some masks have a pocket for an extra layer of fabric, paper towel, or even a coffee filter.
  • FLOW: You should be able to breathe comfortably through your mask. If breathing is difficult because the mask is too heavy or for health reasons (asthma, etc.), choose a lighter mask you can wear as long as possible. A lighter mask is better than no mask at all.

NSF is a global public health organization, with more than 75 years of experience protecting the water we drink, the food we eat, the air we breathe and the environment we share.

To speak to Kim Trautman, or any of our public health experts, please contact Ken Bearden at or +1 734 769 5167.

Share this Article

How NSF Can Help You

Get in touch to find out how we can help you and your business thrive.

What’s New with NSF