Substandard and/or counterfeit PPE endangers human life and safety, and unscrupulous sellers are capitalizing on COVID-19 fears to sell just about anything under labels like "N95." As pointed out here, NIOSH maintains a list of recognized suppliers (and respirator model numbers, with their instructions available for download).

I can't give legal advice but my understanding is that unauthorized use of the logo of the Federal government (e.g. NIOSH, FDA) is a misdemeanor. https://www.usa.gov/government-works "You cannot use government trademarks or government agencies' logos without permission. For example, you cannot use an agency logo or trademark on your social media page." https://www.fda.gov/about-fda/website-policies/fda-logo-policy "The FDA logo is for the official use of the U.S. Food and Drug Administration (FDA) and not for use on private sector materials. To the public, such use would send a message that FDA favors or endorses a private sector organization or the organization’s activities, products, services, and/or personnel (either overtly or tacitly), which FDA does not and cannot do. Unauthorized use of the FDA logo may violate federal law and subject those responsible to civil and/or criminal liability." The problm is that offshore suppliers are out of reach of U.S. law and, as pointed out in the article, U.S. litigation.

One of the cited references, https://www.cdc.gov/niosh/npptl/usernotices/counterfeitResp.html, shows in addition that counterfeiters are not only claiming NIOSH certification, they are using the approved model numbers of reputable companies on their products (counterfeit goods). This could be a strong argument for buying only from U.S. and other companies listed by NIOSH, or their authorized distributors, and not from unknown online sources. This issue also underscores the importance of traceability.