Fig 1.
Demonstration of the assembly of the modified mask.
Photographs of the simple modification demonstrating an individual properly donning the modified mask. (A) Modified mask components consist of a standard ASTM Level 1 surgical mask and two 8” rubber bands. (B) While wearing an ASTM Level 1 surgical mask which has been adjusted to fit along the bridge of the nose, apply one 8” rubber band along the crown of the head and place the front of the rubber band under the nose. (C) Take another 8” rubber band and apply it perpendicularly under the first rubber band so that two loops are formed above and below the first rubber band. (D) Shift the first rubber band so that it is over the bridge of the nose and fold the second rubber band in half on itself along the first rubber band on the horizontal axis. € Place the second rubber band along the cheeks and under the chin. Adjust both rubber bands as needed to achieve a full seal as shown in this anterior view of the final construct. (F) Lateral view of the final construct.
Fig 2.
Study flow diagram from screening to data analysis.
Fig 3.
A comparison of appropriately modified and poorly-modified mask performance using quantitative PortaCount fit testing.
Fit Factor subscores of bending, talking, head side to side, and head up and down, as well as Final PortaCount Fit Factor scores are presented as boxplots. Boxplots are structured such that the horizontal line within the box indicates the median, the vertical length of the box is the IQR, and the whiskers demonstrate the minimum and maximum values excluding the outliers which are circles and stars. Circles are outliers that are 1.5 times the IQR. Stars are outliers that are 3 times the IQR. In each pairing, the properly modified group is on the left and the poorly-modified group is on the right. The dotted horizontal line through the 100 y-axis marker is the passing threshold.
Fig 4.
Comparative summative fit performance between appropriately modified, poorly-modified, unmodified surgical masks, and N95 respirators based on quantitative PortaCount testing.
Boxplots demonstrate the horizontal line within the box as the median, the vertical length of the box as the IQR, and the whiskers as the minimum and maximum values excluding outliers which are circles and stars. Circles are outliers that are 1.5 times the IQR. Stars are outliers that are 3 times the IQR. The dotted horizontal line through the 100 y-axis marker is the passing threshold.
Fig 5.
Subjective secure fit of the modified mask compared to the surgical mask stratified by outcome.
Fig 6.
Subjective comfort of the modified mask compared to the surgical mask stratified by outcome.
Fig 7.
Fit Factor passing rate by test day.