Why are face shields worn during arc welding?

The practice of wearing face shields during arc welding is primarily aimed at protecting technicians from strong ultraviolet (UV) light emissions produced during the welding process. Arc welding generates a brilliant arc of light as the welding electrode discharges electricity across the gap to the workpiece, and this arc emits intense UV radiation which can cause severe skin burns and eye damage known as "arc eye" or photokeratitis.

Face shields are specifically designed to filter out this harmful UV light, providing essential protection to the skin and eyes of the welder. The shields are usually equipped with tinted lenses that not only protect against UV rays but also filter out bright visible light, thus allowing the welder to work safely without the risk of exposure to harmful radiation.

While other options may point to various forms of protection or benefits, the specific and critical role of shielding against UV light is the focal reason for wearing face shields during this type of work.