PPE: A Discussion on Masks and Face Shields

 A guest blog by Loss Control Consultant Troy Walsh

People in Minnesota are now required to wear a face covering in all indoor businesses and public indoor spaces, unless alone. Additionally, workers are required to wear a face covering when working outdoors in situations where social distancing cannot be maintained.

That’s all according to Governor's Executive Order 20-81, effective July 25, 2020.

The League of Minnesota Cities team has received many questions about face coverings. Where do they need to be worn, what is allowed for face coverings, and when does a face shield become an option instead of a face mask? 

We follow the Centers for Disease Control and Prevention (CDC) and Minnesota Department of Health (MDH) guidance on wearing face masks, as well as the option of a face shield.  

• The MDH has provided “Face Covering Requirements and Recommendations under the Executive Order.” 
  
  They say: It is not known whether face shields (a clear plastic barrier that covers the face) provide the same source control for droplets as face masks, but they may be an option in situations where wearing a face mask is problematic. For optimal protection, the shield should extend below the chin and to the ears, and there should be no exposed gap between the forehead and the shield's headpiece.
  
  
• The CDC has also provided information on the mask and face shield decision in their document “Considerations for Wearing Masks.”
  
  They say: It is not known if face shields provide any benefit as source control to protect others from the spray of respiratory particles. CDC does not recommend use of face shields for normal everyday activities or as a substitute for masks. Some people may choose to use a face shield, in addition to a mask, when sustained close contact with other people is expected. If face shields are used without a mask, they should wrap around the sides of the wearer’s face and extend to below the chin. Disposable face shields should only be worn for a single use. Reusable face shields should be cleaned and disinfected after each use.

Face shield protection study

Here’s what we do and don’t know about how face shields can protect us from contracting the coronavirus: Researchers put a face shield on a type of mannequin head encasing a breathing machine and placed it a few feet from another head form spewing droplets of influenza. They measured how much influenza made it behind the face shield, into the mouth of the head form, and down the breathing machine. The face shield did a good job of blocking the cough at first, catching the big droplets. But as the minutes went on, smaller droplets (or aerosols) made their way behind the shield.

Masks are recommended as a simple barrier to help prevent respiratory droplets from traveling into the air and onto other people when the person wearing the mask coughs, sneezes, talks, or raises their voice. Face shields may not provide as much protection to respiratory droplets but are an option — especially if there are medical issues involved with the wearer.  

Up next: Public Safety Professionals and Mental Health

Stay safe, and stay healthy,
Rob and Troy