DISCUSSION
PPE recommended for droplet precautions include gloves, gown, surgical mask and eye protection and or face shield, depending on the anticipated exposure to patient secretions.
Face shield captures body fluid splatters, and alters the particle size distribution and magnitude of inhaled aerosols.(5) It covers a larger area than a face mask with visor or goggles, and limit splash and sprays on to face, surgical masks and respirators, which may increase the risk of self contamination during doffing.(5) Occupational Safety and Health Administration (OSHA) mandates that masks in combination with eye protection devices such as glasses with solid side shields, goggles, or chin length face shields when splashes, spray, splatter or droplets of blood or other potentially infectious material may be generated, and eye, nose or mouth contamination can be reasonably anticipated.(6)
There are several parts to it: Visor, frame, and suspension system.(1) Shields are manufactured from polycarbonate, proprionate, acetate, polyvinyl chloride and polyethylene terephthalate glycol (PETG).(7) It can be disposable, reusable, and replaceable.(1) Acetate provides the best clarity and is scratch resistant.(1) PETG is the most economical.(7) Polycarbonate is most widely used as it offers better optical quality that reduces eye strain associated with face shield wear.(1) Proprionate also has the similar optical quality as polycarbonate, and is the cheaper option.(1, 7) The shields can be treated with coatings to impart anti-glare, anti-static, and anti-fogging properties.(1) The length varies from mid-face to the neck, and the width should reach at least to the point of the ear (recommendation from Centers for Disease Control and Prevention) to reduce the likelihood a splash going around the edge to reach the eyes. Crown and chin protection is recommended for improved infection control purposes.(1) This will reduce the risk of possible ocular inoculation.
There is less retained dermal facial heat, less fogging compared to goggles, can be worn concurrently with other eye PPE, less claustrophobic and can be disinfected easily. It is inexpensive. However some may not fit over certain respirators. Industrial face shields, in the event of face shield shortages tend to be more expensive, heavier and bulkier.