EDITOR:

On November 30, the Daily Press published a letter from me discussing limitations of COVID masks. I have recently been criticized by Brian Black for my letter (December 6). In my letter, I did not differentiate between protection of the wearer versus protection of the person facing the wearer. I did discuss that all of the available masks have a short limited life, after which they don’t protect anyone. After the life of the mask is passed, blowing air around the sides of the mask protects no-one.

In my letter in paragraph one, I discussed the only randomized clinical trial (to date) that studied the efficacy of cloth masks to reduce the spread of COVID. In this study, cloth masks did not reduce the spread of COVID. But, the methodology in this study could not differentiate protection of the wearer versus protection of the person facing the wearer, merely that cloth masks could not reduce the spread of COVID.

In paragraph two, I pointed out that after 3-4 hours, the breath in surgical masks goes in and out around the sides of the mask, and that protects no-one.

In paragraph three, I pointed out that the manufacturers of KN-95 and N-95 believe that they are not effective past 3-4 hours, and require “re-processing,” which practically cannot be done by amateurs. I did not make this up. Look it up yourself.

Brian Black said that he “would expect more from a physician.” I do not know Brian Black, maybe he’s a physician, maybe not. But I would expect better reading-comprehension from a pundit criticizing letters and writing letters to the editor.

Ralph B Blasier

Escanaba