Ralph, Robin,

I noticed that several in the Chat area were virtually begging for an assertion that a face mask provides substantial protection to the wearer.  The earlier webinar on masks was focused on two specific studies and addressed this issue only briefly as an afterthought.

If you will be responding to the participants with answers to many of the questions that were not addressed in the webinar, I suggest it would be very useful to explain that, while a face covering may provide some slight protection to the wearer, its primary function and use is to significantly reduce viral emissions from a wearer who is infected but asymptomatic.  When virtually everyone in a room wears a mask, the viral load in the room is much controlled, although not eliminated, so the risk to all room occupants is notably reduced.  But if enough of the room occupants are not wearing masks, the risk to all in the room begins to approach the level that would be there if no one was wearing a mask.

Peter Zavon, CIH
Penfield, NY

PZAVON**At_Symbol_Here**Rochester.rr.com

Thank you to Frankie, Robin and Ralph for an excellent webinar today!  Not only was the content excellent, it was nice to see your faces since we can’t be together in San Francisco for the National Meeting.

I did have a follow up question that may or may not have made it into the chat.  We normally talk about dilution ventilation and exhausted enclosures for protection from inhalation hazards.  In this situation, however, dilution might just more widely disperse viable virus particles.  You mentioned ionization, UV systems and HEPA filtration to control virus particles but all of those options might require significant time and investment.

Other ideas?

Best,

Debbie

Debbie M. Decker, ACS Fellow

dmdecker**At_Symbol_Here**ucdavis.edu

530.666.0540

916.616.7548

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