Several cases of counterfeiting have already been reported. The Center for Disease Control and Prevention (CDC) has listed out some suspect characteristics of counterfeit respirators. Table 1 below summarizes the main suspect characteristics of counterfeit compared to appropriate FFR. Among the suspect features, there are ear loops designs, the absence of markings or references to national regulation or approval number on the FFR or the presence of flawed ones, the presence of decorative add-ons, a declared approval for children or multiple packaging.
The CDC has provided additional tips for the users to detect unreliable sellers, for example when unlimited stocks are declared or if websites contain bad grammar and other errors. The European Commission offers an alert system for dangerous products, including FFR, to receive reports from the authorities of the member states about suspected products found on the market. Through the EU commission portal, users can search for alerted products, seeing pictures, characteristics and if measures were ordered by public authorities. It is also provided a list of contacts to make a report to national authorities.