From: pzavon**At_Symbol_Here**ROCHESTER.RR.COM
Subject: Re: [DCHAS-L] COVID-19 Question
Date: Mon, 23 Mar 2020 14:25:04 -0400
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Message-ID: 000e01d60140$61400a90$23c01fb0$**At_Symbol_Here**
In-Reply-To <029701d60137$b5a05120$20e0f360$**At_Symbol_Here**>

Something is odd, or off here.


N95 respirators as certified to filter 95% of particles 0.3 microns in size. They are more effective for larger and smaller particles, but I was not aware of anyone assigning a number to any other size range.


Certainly the number for the homemade tea cloth mask is perhaps the most useful for explaining why homemade N95s are not something to try.


Neal, can you provide a like to that article, or at least a reference?



Peter Zavon, CIH
Penfield, NY




From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU> On Behalf Of NEAL LANGERMAN
Sent: Monday, March 23, 2020 1:23 PM
Subject: [DCHAS-L] COVID-19 Question



What do you say to a healthcare provider (assume they are in your core family) who has been told to ration N95 masks. Told to reuse them.

Healthcare provider wants to know about sanitizing them; about effectiveness; about building their own mask.

FYI, here is some NIH published data:


Reduction to exposure by virus-like particulates. Based on article published by NIH

Mask Type                                          % reduction of particulates

N95                                                                 99

SURGICAL MASK                                        74



Also, the Elan Musk companies delivered 50,000 N95 masks to a hospital today.





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