Erratum

In volume 14, issue 2 of the Journal of Occupational and Environmental Hygiene, the incorrect equation appeared in A comparison of facemask and respirator filtration test methods by Samy Rengasamy, et al., pages 92–103. The correct equation (the first equation in the right column on page 97 of the article) is shown below. The publisher apologizes for any inconvenience caused.

$$\begin{array}{c}\hfill \mathrm{MPS}=\frac{{\sum }_{i=1}^6{P}_i\times C_i}{{\sum }_{j=1}^6{C}_j}\end{array}$$