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Two masks can be worse than one: N95 respirator failure caused by an overlying face mask
Jeffrey T Mueller1, Holly D Geyer2, Soroor Karimi3
1Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Phoenix, Arizona.
Abstract:
We have demonstrated the effect of covering an N95 filtering facepiece respirator (FFR) with an overlying face mask. In total, 100 participants successfully completed quantitative fit testing wearing a 3M 1870+ FFR. Among them, 13 (13%; 95% CI, 7%-22%) failed subsequent fit testing when simultaneously wearing a Halyard 47117 procedural mask over the FFR.
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