In Search of a Performing Seal: Rethinking the Design of Tight-Fitting Respiratory Protective Equipment Facepieces for Users With Facial Hair

ConclusionThe results show that sealing against facial hair is extremely problematic unless an excessive force is applied to the facepiece's seal area pushing it against the face. The means of pressure testing devised by the researchers could be seen as a low-cost technique to be used at the early stages of a the design process, before fit testing is viable.
Source: Safety and Health at Work - Category: Occupational Health Source Type: research