Interim Recommendations for Facemask and Respirator Use to Reduce Novel Influenza A (H1N1) Virus Transmission, su cdc.gov, Centers for Disease Control and Prevention, 27 maggio 2009.
«Unless otherwise specified, the term "facemasks" refers to disposable facemasks cleared by the U.S. Food and Drug Administration (FDA) for use as medical devices. This includes facemasks labeled as surgical, dental, medical procedure, isolation, or laser masks... Facemasks should be used once and then thrown away in the trash.»