Chin cup helps to position the facepiece properly.
下巴杯面罩有助于正确位置。
2
Disposable or filtering facepiece respirators are a type of respiratory protection in which the entire respirator facepiece is comprised of filter material.
随弃式呼吸防护口罩是呼吸器的一种，呼吸防护口罩的面罩整体都是由过滤材料构成的。
3
Purchasing reusable respirators also may reduce or eliminate the impact of potential shortages of filtering facepiece respirators and may be more cost effective over the duration of the pandemic.