How Protective Are Face Shields?
Face shields have many benefits over other methods of virus transmission prevention. Face shields are comfortable, they can be disinfected easily, they’re inexpensive, and they have no impact on vocalization, allowing for a more practical solution to prevent the transmission of COVID-19.
That being said, how protective are face shields? How do they protect the wearer from the outside world, and how do they protect the outside world from an infected wearer?
To answer this question, we must first examine the structure of face shields, so we can understand what their effectiveness stems from.
The majority of face shields, as well as other eye and face protection equipment created in the U.S., is designed, tested, and produced following the American National Standards Institute (ANSI) and the International Safety Equipment Association’s (ISEA) standards.
That being said, the three major components of face shields include:
Visors are the lenses or windows that shield the wearer from the outside world. Visors are typically manufactured by a various set of materials including polycarbonate, propionate, or polyethylene terephthalate glycol (PETG.) This makes them affordable, disposable, reusable, and easily replaceable.
The U.S. Centers for Disease Control and Prevention (CDC) are recommending that visors should be of sufficient width to reach at least the point of the ear of beyond it because this will decrease the chances of a splash going around the edge of the face and reaching the eyes. Moreover, visors should have crown and chin protection for the same full-face protection purposes.
Face shield frames are usually made of lightweight plastic. Even though there are a variety of frame styles (adjustable, non-adjustable, fully or partially encircling the head, etc.), the frame itself does not play a major role in increasing disease prevention chances. Its main purpose is ensuring the adjustability of the face shield and the comfort of the wearer.
- Suspension system.
Face shield suspension systems on the market come with either complete or partial circumferential attachments.
Completely circumferential suspension systems can be as simple as plastic headbands that are adjustable for comfort through a specific mechanism, or non-adjustable systems that employ elastic straps. Once again, the emphasis here is on adjustability and comfort.
What are face shields intended to protect you from?
Face shields, in the context of disease prevention, simply provide us with a barrier that shields us against acutely-released aerosols of body fluids. They are commonly used as an alternative to goggles and surgical masks by people in the service industry because they provide a bigger degree of protection against these viral aerosols in the air.
That being said, little is known about the effectiveness of face shields when it comes specifically to the transmission of viral respiratory disease.
A study published in the Journal of the American Medical Association (JAMA) concluded that, when exposed to a cough aerosol simulator loaded with influenza virus, the face shields provided respectively 96 percent and 92 percent reductions in the risk of inhalational exposure.
Medical-grade face shields designed specifically for healthcare professionals do provide an individual with a higher degree of protection when compared to surgical masks or cloth masks. They do not, however, provide a higher degree of protection than medical-grade respiratory masks such as N95.
How do we choose the right face shield?
Face shields are meant to serve as a barrier protecting the facial area of the wearer from airborne body fluids that are expelled from the body due to coughing or sneezing.
Since there is no one standard for face protection against different biological hazards, recommendations on the correct selection of face shields for infection control should be specific to the situation and take into account all available knowledge and the anticipated risks associated with every procedure.
In the best-case scenario, you can find a face shield that has visors treated for anti-fogging and anti-static properties. But practically speaking, face shields should be, at a minimum, full face length with the outermost edges of the face shield reaching to or past the point of the ear to guarantee maximum face protection.
How to use a face shield properly.
Correct use of a face shield is primarily dependent upon appropriate fitting. When fit correctly, face shields will provide you with the most reliable eye protection from airborne virus agents.
If your goal is to protect yourself when you’re outside or at work, make sure you follow these guidelines in order to guarantee a safe face shield fit.
- Face shields should extend lower than the chin.
- Face shields must be placed beyond the ears.
- There should be no gap between the wearer’s forehead and the shield’s headpiece.
Any additional protection that can be used, such as a surgical mask, should still be used. Although the combined effectiveness of different preventative solutions has not been studied, it has become a standard in a lot of procedures.
Where to buy face shields?
If you’re looking to buy face shields for yourself and your family:
Browse Clinical Supplies USA’s collection of face shields in our store here.
If you’re looking to purchase wholesale face shields for sale/distribution to your local community:
Reach out to us an inquire for any purchase above 2,000 units here.
Clinical Supplies USA is an American co-owned and run company specializing in providing quality protective supplies such as KN95 and 3ply masks, hand sanitizers, face shields, gloves, and more.