COVID-19: CDC Guidance on the Wearing of Masks

The wearing of masks continues to be a hot topic. With that in mind, see the current mask guidance from the Centers for Disease Control (CDC), Considerations for Wearing Masks

There were two areas of the guidance that I found of interest to since I've observed the use of the masks with valves and other people wearing a face shield, with or without a mask. That guidance is below:

Masks with Exhalation Valves or Vents

The purpose of masks is to keep respiratory droplets from reaching others to aid with source control. However, masks with one-way valves or vents allow air to be exhaled through a hole in the material, which can result in expelled respiratory droplets that can reach others. This type of mask does not prevent the person wearing the mask from transmitting COVID-19 to others. Therefore, CDC does not recommend using masks for source control if they have an exhalation valve or vent.
Face Shields

A face shield is primarily used for eye protection for the person wearing it. At this time, it is not known what level of protection a face shield provides to people nearby from the spray of respiratory droplets from the wearer. There is currently not enough evidence to support the effectiveness of face shields for source control. Therefore, CDC does not currently recommend use of face shields as a substitute for masks.
However, wearing a mask may not be feasible in every situation for some people for example, people who are deaf or hard of hearing—or those who care for or interact with a person who is hearing impaired. Here are some considerations for individuals who must wear a face shield instead of a mask:

-Although evidence on face shields is limited, the available data suggest that the following face shields may provide better source control than others:
-Face shields that wrap around the sides of the wearer’s face and extend below the chin.
Hooded face shields.
-Face shield wearers should wash their hands before and after removing the face shield and avoid touching their eyes, nose and mouth when removing it.
-Disposable face shields should only be worn for a single use and disposed of according to manufacturer instructions.
-Reusable face shields should be cleaned and disinfected after each use according to manufacturer instructions or by following CDC face shield cleaning instructions .
-Plastic face shields for newborns and infants are NOT recommended.