Face Shields for Instructional Use

by Office of the Provost and Senior Vice President for Academic Affairs

To help ensure the safety of our classroom environments, Michigan Tech is producing a face shield specifically designed for instructors to use while teaching face-to-face in a classroom. The shield permits visibility of the instructor’s full face, both for in-person students and those who may be joining via video conference, and is sufficiently comfortable to be worn for more than an hour. 

David Holden and John Schneiderhan from the Van Pelt and Opie Library and many others have worked tirelessly over the summer months to develop the “teaching shield.” Their work began with a successful open-source model for medical personnel — the same model the University modified to produce a face shield for frontline COVID-19 responders. 

The original design was tested and modified for different aspects of usability in an instructional setting:

  • Bharath Lavu and John Schneiderhan conducted break-point strength and flexibility testing of numerous halo modifications in support of long-term comfort and durability.
  • Josh Loar conducted a sonic analysis of different shield shapes and recommended a type of microphone best suited for video conferencing while wearing a shield.
  • Will Cantrell’s and Raymond Shaw’s research groups conducted an assessment of the reduction of respiratory particles in close quarters.

Prototypes were distributed to approximately 14 faculty members to gather comments and feedback. Most of the faculty concerns were related to glare reduction, greater coverage around the head and chin, overall fit and comfort, and fragility during repeated use. 

As a result of addressing these concerns, the current model is 58% more flexible than the original, permitting a more comfortable fit for a variety of head sizes, while being fivefold more break-resistant under repeated use. The shape of the shield was also extensively modified; the current model wraps around the head more fully and is flatter across the face to reduce glare, both inside and outside the face shield.

Sonic analysis demonstrated that a flat-front design was inferior to a rounder shape, both in the clarity of speech and compatibility with a microphone. The current design preserves the rounded shape near the mouth while working to reduce glare as much as possible. Microphones with a thin boom and an over-the-ear design were deemed to work best with the designs tested.

Researchers also tested the ability of the face shield to reduce respiratory droplets. In a tightly controlled, enclosed-space test that represented a “worst-case scenario,” the shield reduced the detection of respiratory-sized particles at a distance of one foot to almost below the detection limit. The researchers cautioned that additional, more sophisticated testing would be necessary to determine the extent of any reduction, if any, of smaller aerosol particles.

With the introduction of these shields to a much wider set of users, the designers look forward to continuing to improve and refine the design for even greater glare reduction, long-term fit for a wide variety of head sizes, durability and maintenance, and audio quality. In working to ensure classroom safety, the face shields represent one very visible measure that complements all other safety measures being taken at Michigan Tech this fall.