Respirators and protective masks with valve
With valve
— masks and respirators equipped with an exhalation valve — a special device that allows exhaled air to freely escape.This feature enhances product usability in several ways. Firstly, it prevents air from lingering and moisture accumulation under the mask, allowing prolonged use without compromising comfort and safety. Secondly, the valve ensures effortless and natural exhalation without requiring additional effort. Thirdly, it minimizes the escape of exhaled air from the top edge, which is crucial when wearing glasses, preventing lens fogging.
However, the drawback to these benefits primarily lies in the limited effectiveness of valve-equipped products as anti-epidemic protection against COVID-19 and other airborne infections. In this application, masks and respirators should safeguard both the wearer and those around them in case the wearer is a disease carrier. While there's usually no issue with the first task, the valve scarcely impedes the exhalation of "infection." Consequently, some countries explicitly prohibit the use of masks and respirators with valves in public spaces based on sanitary and epidemiological rules.