From: Dawn Toon <dt100**At_Symbol_Here**WELLESLEY.EDU>
Subject: Re: [DCHAS-L] dry heat for disinfection of PPE
Date: Thu, 26 Mar 2020 09:59:45 -0400
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Message-ID: CAOQRFwaSmHx8Xjy0kiB8ciuTE-_J+PvaVh01wTwdg4vt1cXePQ**At_Symbol_Here**mail.gmail.com
In-Reply-To


The following document provides information regarding the reuse of respiratrators, from The National Academies Press

Coronavirus Resources Collection

This collection is a compilation of resources related to COVID-19. Publications explore prevention, response, and recovery from pandemic infectious disease.


Dawn

Wellesley College
Dawn Toon
Environmental Health and Safety
EHS Officer
413-687-44426


On Wed, Mar 25, 2020 at 2:26 PM Jack Reidy <jreidy2**At_Symbol_Here**stanford.edu> wrote:

All,

Please be careful about drawing conclusions from this document. It lacks information about controls, method specifics, brand/model of N95, sample size, error bars, and any information about how the processes affect the actual fit. In 3M's bulletin, they noted that very few of the methods affected the filter, but most affected the fit.

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> On Behalf Of NEAL LANGERMAN
Sent: Wednesday, March 25, 2020 10:54 AM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: Re: [DCHAS-L] dry heat for disinfection of PPE

I have reviewed the Stanford document and based on it, I have opted for the steam method. Most non-specialized ovens are difficult to control at 70C. Boiling water is easy to control.

Here are the instructions I have written to implement the steam approach:

. Masks must be handled carefully to avoid excessive contamination. Once a mask is removed, suspend it near the top of a large pot with 5-8 cm of water in it. Place the cover on the pot and heat the water to boiling. Reduce the heat to sustain a slow boil and set a timer for 10 minutes (you can extend this to perhaps 12-13 minutes). Keep the lid on the pot during this time. At the end of the steaming interval, remove the respirator and allow it to drip/drain excess water and air dry. Inspect the mask for damage, and if OK, it is ready to reuse.

Until the PPE availability problem is resolved, we will need to take approaches like this, which balance risk versus need and do our best to help the frontline healthcare community.

nl

Reply from:

NEAL LANGERMAN

(619) 990-4908

From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU> On Behalf Of Lawrence M Gibbs
Sent: Wednesday, March 25, 2020 10:30 AM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: [DCHAS-L] dry heat for disinfection of PPE

This is non-peer reviewed information from a Stanford research group, as indicated in the material. But the data may be useful.

The direct URL is here: https://stanfordmedicine.app.box.com/v/covid19-PPE-1-1

From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU> On Behalf Of Ernest Lippert
Sent: Wednesday, March 25, 2020 10:21 AM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: Re: [DCHAS-L] COVID-19 Question

All,

I have not followed the sterilization discussion in detail. Has high temperature dry treatment been evaluated? I wonder if 5-10 minutes at 50-60 deg C, for instance, inactivate the virus without doing damage to the item?

Ernest Lippert


From: "James Keating" <james.k.keating**At_Symbol_Here**GMAIL.COM>
Sent: Tuesday, March 24, 2020 7:36 AM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: Re: [DCHAS-L] COVID-19 Question

Steve,

This Email started out as a well-intentioned response to your question started about irradiating N95 Respirators but alas it got out of hand. I have rambled on until this response degenerated to the obtuse dissertation on irradiation in general as well as COVID19.

If you took the time to read this monster you have the patience of a Saint.

Digression: I have always had an issue with the term irradiation when it come to food. Technically, to irradiate something involves the transmutation of an isotope by expose it to neutron bombardment and typically producing one or more radioactive isotopes either on purpose to create source material or as an ancillary consequence of power generation using a nuclear reactor. On the other hand, exposing food to the gamma radiation from a powerful source or industrial x-ray machine does not make the food radioactive. However, it does kill bacteria, fungus or viruses. Perhaps we need a different term for this process to satisfy eggheads like me.

Irradiation of food requires a gamma source of very high strength e.g. hundreds of Curies of 60CO along with expensive environmental, security, trained personnel and health physics safe guards. This would be prohibitively expensive and time consuming for merely zapping N95 masks. By the way, unless the laws have changed since I was last employed in the radiological safety discipline, irradiation of food is not legal in the United States. However, If we did irradiate fruit for example we could harvest at peak ripeness. Then we could ship it globally as delicious vine ripened fruit instead picking it green and letting ripen in the create and then on the shelves for weeks resulting the hard, mealy unappealing fruit I am usually stuck with. Instead of the tasty morsel we all deserve.

Let's hear it for food irradiation, it is by far the best method of naturally preserving any food and without chemicals, pasteurization, freezing drying or a host of other methods that ruin the flavor and reduce nutritional value, while the germ killing efficacy of those primitive methods remains questionable. We don't know how long that frozen or refrigerated food sat in the hot sun on the loading dock or trailer waiting to be transferred to a hot store room and finally moved to the cooler or freezer when the employees finally got around to it - perhaps a shift or even a whole day later. Appetizing thought.

Further digression: By the way, wearing an N95 respirator without tight fitting goggles may be a placebo. Fortunately the COVID19 virus appears to be a rather mild airborne pandemic. For example, last year (2018-19) the flu killed 80,000 Americans and was contracted by more than 500,000,000 people worldwide with half a million deaths.

The latest CDC estimate of the American fatality rate is about 1.5%. The doctors and CDC professionals on television seem to agree that at least 85% of the people who contract Covid19 will get over it and most with little or no symptoms, this computes to an adjusted or weighted rate of about two tenths of one percent (0.002) and almost all of those fatalities are very old and in poor health with existing health problems. .

Although there are some statistical outliers about 95% of fatalities are over 80 years old and/or have immune systems, COPD, Diabetes or a host of other serious health conditions. 99% of the fatalities in China and Italy were over 80 years old and most were in nursing homes already. Half the fatalities in Washington State were very old patients in the same nursing home.

For a bit of perspective: last 4,866 Americans (that we know of) died in the bath tub as a result of falls and drowning. Over 30,000 deaths in car accidents, about 30,000 suicides and 200,000 died from HID (Hospital Induced Death) as in MERSA and other diseases and mostly medical mistakes and misdiagnosis. Life itself is apparently a hazardous activity.

Perhaps those most at risk should take personal responsibility and self-quarantine and the rest of society should practice social distancing. If you must travel drive do not take crowed public transportation, avoid crowds, wash hands frequently, disinfect what you use, take care not to cross contaminate.

If you must fly (really must) wear a tight fitting for real half-face respirator (like a painters mask) with a P100 filter along with goggles. Carry and use germicide frequently. When you reach you destination decontaminate your bags with germicide. Wear the same getup in a cab or uber.

Hope for the best continue your life as best you can, stay away from any at risk people like Grandma and maybe you Mother in law.

If you develop any symptoms or think you have isolate and self-quarantine immediately and use the soon to be available test kits.

Yours Truly,

Jim Keating

From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU> On Behalf Of Rupkey, Steve
Sent: Monday, March 23, 2020 4:44 PM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: Re: [DCHAS-L] COVID-19 Question

Hello:

Has anyone considered irradiation of the N-95 respirators, using commercial food irradiation equipment?

I know a plan must be developed to collect, store, transport, etc. the respirators, but any thoughts on the concept?

Thanks,

Steve Rupkey

From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU> on behalf of Michael <mabuczynski**At_Symbol_Here**HOTMAIL.COM>
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Date: Monday, March 23, 2020 at 3:32 PM
To: "DCHAS-L**At_Symbol_Here**PRINCETON.EDU" <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Subject: Re: [DCHAS-L] COVID-19 Question

The N-95 is classified as a "Single use disposable respirator" These were not meant to be reused and OSHA requires a form to filled out that the user understands the limitations and knows how to don and doff the unit under normal circumstances.

The problem with any respirator including reusable types is the decontamination and storage after use/cleaning. As a former OSHA Industrial Hygienist, I often enforced the respiratory standard with all of these requirements.

Now I know there is a current emergency and of course everyone is looking for an interim solution to extend life. To develop a procedure to decontaminate the N-95 you must be aware of not destroying the integrity( bleach???). We do know that the 91% isopropanol works without destroying the material. Then you must look at the way you are handling the used respirators as not to spread further contamination. Next step is the storage before the next use (new baggie!)

It may be helpful to contact NIOSH and/or the manufacturer (3M for example) and ask them for their recommendations. I would expect given the recent emergency/need vs shortage they are working on a possible solution.

Mike Buczynski


From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU> on behalf of Monique Wilhelm <mwilhelm**At_Symbol_Here**UMICH.EDU>
Sent: Monday, March 23, 2020 2:08 PM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Subject: Re: [DCHAS-L] COVID-19 Question

A friend who is a surgical nurse has explained to me that they are
using the cloth masks to cover their N-95s so that they can remove the
cover mask and replace if there is a noticeable splatter incident,
thereby making the N-95 masks effective for a longer period. They are
then reusing the N-95 without specific instruction for storage....she
asked me how to store. I have no answer.

Monique

_________________________________________________________

Monique Wilhelm, M.S., NRCC Certified CHO

ACS CHAS Secretary|2017 CERM E. Ann Nalley Award Recipient

Laboratory Manager|Adjunct Lecturer|Chemistry Club Advisor

Department of Chemistry & Biochemistry|University of Michigan-Flint

Emaill: mwilhelm**At_Symbol_Here**umich.edu




Monique

_________________________________________________________

Monique Wilhelm, M.S., NRCC Certified CHO

ACS CHAS Secretary|2017 CERM E. Ann Nalley Award Recipient

Laboratory Manager|Adjunct Lecturer|Chemistry Club Advisor

Department of Chemistry & Biochemistry|University of Michigan-Flint

Emaill: mwilhelm**At_Symbol_Here**umich.edu






On Mon, Mar 23, 2020 at 3:03 PM Lawrence M Gibbs <lgibbs**At_Symbol_Here**stanford.edu> wrote:
>
> Hi Tried sending this with document attached but was rejected by site. So am placing a link here that I hope will get one to the site of the same document: Final Report for the Bioquell Hydrogen Peroxide Vapor (HPV) Decontamination for Reuse of N95 Respirators
>
> http://wayback.archive-it.org/7993/20170113034232/http://www.fda.gov/downloads/EmergencyPreparedness/Counterterrorism/MedicalCountermeasures/MCMRegulatoryScience/UCM516998.pdf
>
>
>
> From: Lawrence M Gibbs
> Sent: Monday, March 23, 2020 11:04 AM
> To: neal**At_Symbol_Here**CHEMICAL-SAFETY.COM; DCHAS-L**At_Symbol_Here**PRINCETON.EDU
> Subject: RE: [DCHAS-L] COVID-19 Question
>
>
>
> Neal et al,
>
>
>
> Keep in mind particulate filtering respirators were developed primarily for inert particulate matter (wood dust, silica, etc.). When used in a clinical setting, the particulate matter is no longer inert, but potentially can replicate and infect individuals upon exposure (uptake). For this reason, reuse of an N-95 is not typically recommended for use in biohazard protection, as a general rule.
>
>
>
> Having said that we are entering that stage of an emergency where scarcity of the primary protective device is occurring. A number of academic clinical centers are running into the same issues and are doing some testing of methodologies for possible reuse of n-95 particle respirators. The attached is one such report on methodology for disinfection of the masks for possible reuse. Note that gas or vapor is needed to assure complete penetration of the filtrate substrate where infectious particulates may adhere. Work is currently being done by some of the regional academic bio research facilities on this and protocols being developed demonstrating the process and testing using indicator strips of the disinfection. I suggest caution on applying considerations for non-viable particulates to the current situation for N-95s or other respiratory protective equipment.
>
>
>
> Larry
>
>
>
> Lawrence M. Gibbs, CIH, FAIHA
>
> Associate Vice Provost Emeritus
>
> Stanford University
>
> lgibbs**At_Symbol_Here**stanford.edu
>
> (c) 650-387-1131
>
>
>
>
>
>
>
> 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 10:23 AM
> To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
> Subject: [DCHAS-L] COVID-19 Question
>
>
>
> All
>
> 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
>
> HOMEMADE TEA CLOTH MASK 58
>
>
>
> Also, the Elan Musk companies delivered 50,000 N95 masks to a hospital today.
>
>
>
> nl
>
>
>
> ------------------------------------------------------------------------------------
>
> Safety is the practice of fixed and unbendable principles, the first of which is to be flexible at all times. Paraphrase of Everett Dirksen.
>
> The information contained in this message is privileged and confidential and protected from disclosure. If the reader of this message is not the intended recipient, or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by replying to the message and deleting it from your computer.
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>
>
> ACSafety has a new address:
>
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>
> ADVANCED CHEMICAL SAFETY, Inc.
>
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