Single-use respirator: A respirator without a replaceable filter, intended to be discarded after excessive resistance to breathing, reduction in filtration capacity, hygienic considerations, or physical damage that renders it unsuitable for further use. A filtering facepiece is one type of single-use respirator.
Social distancing: Public health measures targeted at minimizing nonessential close contact with others, e.g., temporary closing of schools to reduce influenza transmission among children.
Sterilization: The complete elimination of all forms of microbial life.
Surgical mask: One of two kinds of medical masks. Surgical masks, which were originally designed to protect the operating field from contaminants generated by the wearer, are of two main types: (1) flat-pleated or duck-billed in shape, conforming to the bridge of the nose with a flexible piece and affixed to the head with two ties and (2) premolded, conforming to the bridge of the nose with a flexible piece and adhering to the head with a single elastic. In the context of this report, unless otherwise specified, a surgical mask has passed certain ASTM tests required by FDA.
Thoracic particles: Particles having a mass median aerodynamic diameter smaller than 10 µm.
Tight-fitting respirator: Type of respiratory inlet covering that requires a complete seal with the face of the wearer. Available as half masks and full facepieces.
User seal check: An action conducted by the user each time the respirator is donned to determine if the device is properly seated on the face. A user seal check, like the initial fit-testing, is an essential prerequisite for effective respirator use. (Synonym: Fit Check)