Mike and colleagues:

Duke University Hospitals has developed a very successful method using hydrogen peroxide and have presented a webinar on the method. It has been quite successful and is very well vetted by a highly respected group of industrial hygienists, virologists, medical doctors, etc.

Please take a listen to their approach (which is in practice today).

https://www.safety.duke.edu/news-events/webinar-n95-decontamination-using-h2o2

Zack

S.Z. Mansdorf, PhD, CIH, CSP, QEP

Consultant in EHS and Sustainability

7184 Via Palomar

Boca Raton, FL 33433

561-212-7288

Here's the eagerly awaited NIOSH document summarizing the current situation. The paper bag method is at the very beginning. Useful tables address the other methods. And there is a warning that none of these methods is as good as getting a new N95 after each use.

https://www.cdc.gov/coronavirus/2019-ncov/hcp/ppe-strategy/decontamination-reuse-respirators.html

Mike

No. Some disinfectants are toxic if inhaled, they may compromise the integrity of the melt-blown fabric that the facepiece uses, and five days should be enough to sufficiently degrade the virus. However, I was only reporting what I've heard NIOSH is concluding. The guidance document isn't out yet.

=EF=BB=BF

NIOSH is about to come out with new guidance on disinfection and reuse. As I understand it, the Battelle system will get high marks. And one expedient is to put a used N95 in a paper bag for five days before reusing it, since there's pretty fair evidence that the virus will be sufficiently degraded in 2-3 days. We've been urging them to say in the guidance that these are stopgap measures, not as protective as getting a new respirator after every use, and only to be used in a supply crisis.

 

These are excruciating problems. We're talking to health care workers every day who are short of not just respirators, but gowns, face shields, booties, gloves. And for their patients the projected shortages aren't just beds and ventilators but, in one case, IV tubing. There's enough blame to go around, but some of it falls on hospital administrators, who take pride in running a hospital "like a business," and think an MBA outweighs a MPH or MD. And that's equally true for the "nonprofit" hospitals. Just-in-time supply works well in an auto plant. Not in a hospital; not in a pandemic.

 

Mike  

 

Michael J. Wright

Director of Health, Safety and Environment

United Steelworkers

 

412-562-2580 office

412-370-0105 cell

 

"My friends, love is better than anger. Hope is better than fear. Optimism is better than despair. So let us be loving, hopeful and optimistic. And we'll change the world."

                                                                                                                                                                                         Jack Layton

 

 

 

 

From: ACS Division of Chemical Health and Safety [mailto:DCHAS-L**At_Symbol_Here**PRINCETON.EDU] On Behalf Of jeskiekb**At_Symbol_Here**comcast.net
Sent: Monday, March 30, 2020 2:47 PM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: Re: [DCHAS-L] N-95 disinfection and reuse

 

I haven't had time to read through the full set of emails on this, so sorry if this is a repeat. Battelle has some basic information on the system on the website. 

 

https://www.battelle.org/inb/battelle-critical-care-decontamination-system-for-covid19

 

Sent from my Verizon LG Smartphone

 

------ Original message------

From: Monona Rossol<0000030664c37427-dmarc-request**At_Symbol_Here**LISTS.PRINCETON.EDU>

Date: Mon, Mar 30, 2020 1:26 PM

T! o: DCHAS-L**At_Symbol_Here**PRINCETON.EDU;

Cc:

Subject:Re: [DCHAS-L] N-95 disinfection and reuse

 

Well, thank you Jack and Stanford.  Finally a nice clear presentation on these issues stating what we all probably knew  deep in our kishehs.  Monona

-----Original Message-----
From: Jack Reidy <jreidy2**At_Symbol_Here**stanford.edu< a="">></jreidy2**At_Symbol_Here**stanford.edu<>
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Sent: Mon, Mar 30, 2020 12:11 pm
Subject: Re: [DCHAS-L] N-95 disinfection and reuse

All,

 

As a side note, if you saw the original version of the Stanford item, they have since expanded on it significantly, including adding many disclaimers. https://stanfordmedicine.app.box.com/v/covid19-PPE-1-1

 

Sincerely,

 

Jack Reidy (he/him)

Research Safety Specialist

Environmental Health & Safety

Stanford University

484 Oak Road, Stanford, CA, 94305

Tel: (650) 497-7614

 

 

 

From: ACS Division of Chemical Health and Safety <dchas-l**At_Symbol_Here**princeton.edu< a="">> </dchas-l**At_Symbol_Here**princeton.edu<>On Behalf Of Reinhardt, Peter
Sent: Friday, March 27, 2020 12:48 PM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: [DCHAS-L] N-95 disinfection and reuse

 

Colleagues,

 

On 25 March the Stanford School of Medicine published a nice Q&A on the shortage of face masks and N-95 respirators. See file:///Users/pareinhardt/Downloads/mask-ppe-EBM-Stanford%20Medicine%20v1.2-3-25-2020.pdf

 

On pages 5-6 there is a good discussion of the various methods that can be used to disinfect N-95s, including a helpful table and references. One refence shows that hot water vapor from boiling water for ten minutes is an effective decontamination method.

 

At Yale, we plan to use vaporized hydrogen peroxide to decontaminate and reuse N-95s using the methods described here:

 

https://www.safety.duke.edu/sites/default/files/N-95_VHP-Decon-Re-Use.pdf

 

https://www.fda.gov/media/136386/download

 

Pete Reinhardt

Director, Yale Office of Environmental Health and Safety

 

--- For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here**dchas.org Follow us on Twitter **At_Symbol_Here**acsdchas

--- For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here**dchas.org Follow us on Twitter **At_Symbol_Here**acsdchas

--- For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here**dchas.org Follow us on Twitter **At_Symbol_Here**acsdchas

--- For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here**dchas.org Follow us on Twitter **At_Symbol_Here**acsdchas

--- For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here**dchas.org Follow us on Twitter **At_Symbol_Here**acsdchas

--- For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here**dchas.org Follow us on Twitter **At_Symbol_Here**acsdchas

--- For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here**dchas.org Follow us on Twitter **At_Symbol_Here**acsdchas

--- For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here**dchas.org Follow us on Twitter **At_Symbol_Here**acsdchas