Emergency Use Authorizations for the Decontamination of N95 Respirators

May 6, 2020

The U.S. Food and Drug Administration has issued emergency use authorizations for select sterilization systems that will allow N95 or N95-equivalent respirators to be decontaminated. The sterilization systems will help address the shortage of these vital masks used by healthcare workers to protect themselves from exposure to the novel coronavirus. 

This May 4 webinar features an expert from 3M who addresses the 3M perspective on the decontamination of N95 respirators and shares important caveats about doing so, as well as representatives from STERIS, Battelle, Advanced Sterilization Products (ASP), and Sterilucent, each of whom have systems covered by EUAs. Following the expert presentations, is a Q&A session.  

Watch on YouTube


  • Amanda Benedict, acting vice president of standards at AAMI (host and moderator) 

  • Jessica Hauge, application engineering specialist in the personal safety division at 3M.  

  • Chris Antonucci, senior director of marketing at STERIS 

  • Bill Brodbeck, senior director of regulatory affairs at STERIS 

  • Jeremy Yarwood, vice president of research and development at ASP  

  • Peter Kalkbrenner, director of engineering at Sterilucent  

  • Will Richter, principal research scientist, Battelle. 

Systems covered under EUA that are addressed include: 

  • STERIS: STERIS V-PRO 1 Plus, maX, and maX2 Low Temperature Sterilization Systems 

  • Battelle: Battelle CCDS Critical Care Decontamination System 

  • ASP: STERRAD 100S, NX, and 100NX Sterilization Systems 

  • Sterilucent: Sterilucent HC 80TT Hydrogen Peroxide Sterilizer 


Rob Jensen, president and CEO of AAMI 

I'd like to thank everyone who took time out of what are obviously very busy days today to join us. We understand that a lot of you are on the front lines, or immediately behind the front lines, helping patients out there get the best clinical care they can even though they're affected by COVID-19, and we truly appreciate you taking time out. I also want to thank the expert panelists from industry who are joining us to talk about their work, and they are ensuring that the healthcare workers have the PPE, particularly the respirators, that they need to perform their jobs safely during this pandemic. 

Amanda Benedict (00:02:20) 

To give some context for today's webinar. Over the past couple of months, AAMI has hosted a number of webinars that have focused on the COVID-19 pandemic. One of the biggest areas of concern we've heard from those who have joined the webinars and from our members and other folks out there in healthcare delivery is how to respond to the shortages of N95 masks. There's an extreme demand for respirators that has far outpaced the supply of respirators. So institutions and hospitals have been looking to the existing standards, the guidance that they've received from manufacturers. Many institutions are developing their own policies and procedures for mask decontamination and reuse, trying to balance the need for protecting their staff and patients with a very unpredictable supply, and sometimes nonexistent new respirators. 

The U.S. Centers for Disease Control and Prevention has put forward strategies that help to optimize the supply of personal protective equipment, including limited reuse of disposable N95 respirators as a crisis strategy. And I would encourage our audience to review that guidance if you haven't already. In recent weeks the FDA has released a number of emergency use authorizations or EUAs pertaining to N95 mask decontamination. In this webinar we are going to feature an expert from 3M who addresses the 3M perspective on decontamination of N95 respirators, and we'll share some important caveats about doing so, as well as representatives from some of the companies that have existing emergency use authorization. So there's Advanced Sterilization Products, or ASP, Sterilucent, and Battelle, each of whom have systems that are covered by EUA. And following the expert presentations, we will have a Q & A session. Now to get started, I'd like to pass off the webinar to Jessica Hauge to lead us into her presentation from 3M. 


Jessica Hauge (00:04:26) 

My name is Jessica Hauge and I am an application engineer for 3M's personal safety division. I have a master of public health degree and a background in occupational health and safety. I support 3M's respiratory protection products including our N95 disposable respirators and other filtering facepiece respirators around the world. I want to say thank you so much to AAMI for the opportunity to be part of this panel. I also want to take a moment to say thank you to the heroic healthcare workers, emergency responders, and other essential workers who are working so hard to get us through this crisis.  

Just very quickly, this presentation is based upon U.S. regulations as they stand today. However, they are subject to change and regulations may vary in different parts of the world. Also user instructions for all products and equipment should always be followed.  

Whenever we discuss decontamination of N95 respirators, we should first acknowledge the full context for the practice of decontaminating N95s at this moment in time. In early February, as was just mentioned, in the face of a global shortage of filtering facepiece respirators, the U.S. Centers for Disease Control and Prevention [CDC] issued their first set of very detailed recommendations for how to optimize the use of those available N95 respirators. Since then, the CDC has built out their guidance and also organized their recommendations into three tiers or stages of this pandemic. 

The first is conventional capacity strategies or approaches that can always be undertaken to reduce organization's use of PPE. The second is contingency capacity strategies, which CDC indicates may be implemented during times of expected shortages of N95. The final is crisis strategies which may be implemented during known shortages of N95. The CDC reminds organizations in their guidance that the hierarchy of control should always be considered. So in other words, engineering and administrative controls should always be implemented first, preferentially, before relying upon, or in some cases in addition to relying upon, personal protective equipment such as respirators. 

And if we look specifically at the strategies that relate to how respirators are used, we have here the first strategy is using other respirator types. So that includes elastomeric half facepieces, perhaps elastomeric full facepieces and powered-air purifying respirators or PAPRs. The second option that is listed among the CDC strategies is extended use of N95, so that means basically to not use respirators—N95 respirators—as an option that should be discarded after every patient interaction, which is probably a conventional infection control practice that is in place during normal times of operation. The third option there is using N95s as respiratory protection when they are beyond their shelf life. So that now we are into the crisis capacity set of strategies here. Option number four is outlined in CDC's guidelines specifically regarding decontamination of N95 respirators. And this basically says that a respirator should be put in a breathable bag after it's used and then after a period of five days it can be reused. CDC says that that practice is preferred over other decontamination methods. So when we get to the fifth option there, that's decontamination, which is basically included in the strategies as nearly a last resort.  

On April 24th, OSHA [Occupational Safety and Health Administration] published an enforcement memo, which effectively means that employers can adopt the practice of decontaminating N95s as a last resort and still be in compliance with the OSHA respiratory protection standard during this time of the COVID-19 pandemic. And in this memo, OSHA provides these lists of the contamination methods. First, a set of methods that OSHA says, based on the available research, are most promising. And they include vaporized hydrogen peroxide, UV germicidal irradiation, and moist heat. Then they provide another list of options that are possibly suitable if none of the options in the first list are available. And these included microwave-generated steam and liquid hydrogen peroxide. And then OSHA also provides this list of methods that they say are not recommended based on the research that has been done so far. 

OSHA also emphasizes in this enforcement memo, using the same wording as the CDC does in their guidance, that manufacturers of respirators should ideally be the entities which determine which decontamination methods are acceptable for use with their very specific respirator models, from a compatibility standpoint. 

And then it's important to note that the compatibility of the decontamination method, it varies by respirator model. N95s are made of variable materials and with variable designs. Even within 3M's own portfolio of filtering facepiece respirators, there are several variations in structure and materials. And that is the reason why OSHA and the CDC indicate that it's important for manufacturers to be involved in evaluating the compatibility of these methods with filtering facepiece respirators. 

OSHA also goes on to explain that there are four factors that should be addressed during the evaluation of whether a decontamination method is an acceptable approach. And these are the same four criteria that we at 3M have published in some of our technical support materials.  

Those four criteria, and I'm sure everybody on this call is fairly familiar with these at this point, there is efficacy—so of course the method must inactivate the target organism—and safety. So 3M relies upon the method developers for both of these factors to confirm the efficacy and also the safety of a method. And by safety we basically mean that a decontamination method should not create risks by potentially exposing healthcare workers to residuals when they wear the respirators after they've been treated. And one noteworthy example of this—this is a method that we believe should automatically be disqualified from consideration—and that's ethylene oxide because of the level of risk it poses [inaudible 00:11:20] . 

And then the third criteria on there is filtration and the final is fit. So a decontamination method must not negatively impact the respirator's ability to perform it's filtration function and also its ability to seal to the wearer's face. For years 3M has evaluated the impact of various decontamination methods from the filtration and fit performance of a variety of our filtering facepiece respirators. And during this pandemic we have partnered with the [method] developers to continue this work, evaluating the samples of our respirators that have been treated using methods that were specified by the developers.  

So when we received treated samples from our partners, we do evaluate both the filter performance and the fit performance in order to account for those—the third and the fourth criteria on the list of four criteria. For filtration evaluations it's important to note that the PortaCount is not an acceptable way to evaluate the filter performance of a respirator. The PortaCount is designed to evaluate the fit of a respirator and it's effective at doing that for N95s because it selectively detects only a very narrow range of particles within the full particle size range. It targets that narrow range of particles because those are particles that are expected to be filtered with an extremely high efficiency, for the instrument is trying to detect particles that enter the respirator through a breech, not a seal. And because it's so selective, it may not accurately measure the filter performance across the full range of airborne particle sizes. So in our lab we evaluate filtration performance using instruments such as the TSI Automated Filter Tester 8130. And that is the instrument that is also used to generate filter data for meeting the national performance standard for respirators. 

And then for fit evaluations, we examined the various components of each of our respirator models that may have an impact on the respirator's ability to seal to the wearer's face, including the headbands, the nose foam, and the condition of the cup itself. And then some of our evaluations also involve measurements of fit performance.  

So like I said, we've evaluated decontamination of filtering facepiece respirators for many years. And when this pandemic began to ramp up, we entered this space of evaluating decon methods with a pretty good understanding for what our likely starting point should be, which methods were likely to meet all four of the criteria. The framework of the emergency use authorizations that are being issued allows a level of specificity that is important for this process of basically clearing methods as being compatible with our products. As this audience knows, there are many subtle differences between systems and cycles that could paint very different pictures from a compatibility standpoint. And with these EUAs in place, we are able to, in partnership with method developers, identify methods in a very specific way to help healthcare organizations implement the method as it was performed during treatment of the respirator samples that we then evaluated. 

So we have identified certain decontamination systems in each of these four categories. There's vaporized hydrogen peroxide, environmental vaporized hydrogen peroxide, UV light, and also moist heat. I'm not going to go into great details on the methods because we will be hearing from many of the method developers next. But we continue to conduct additional evaluations to expand the list of systems that are compatible with our respirators. And we publish this information in a technical bulletin that's updated approximately weekly with new information. 

At this moment, we're also working to broaden the scope of our guidance so that is more globally applicable. We began here in the U.S. and we are now working with our 3M counterparts, global counterparts, and our external partners around the globe. And on that note, thank you so much to all of our partners who have been working with us and continue to work with us in this very important endeavor. And I also need to acknowledge my very dedicated colleagues at 3M whose hard work has made it possible for us to make these recommendations. And now I will hand it off to the next speakers who are William Brodbeck and Chris Antonucci of STERIS. 


Chris Antonucci (00:16:22) 

Thank you very much. This is Chris Antonucci with STERIS. I'm the senior director of marketing for STERIS's Infection Prevention Technology division and as mentioned, Bill Brodbeck is our senior director of regulatory affairs. 

I just wanted to take a few moments to walk through kind of the high level of what the process and the claims look like with STERIS's emergency use authorization. And I want to take a moment to thank AAMI for extending the invitation and allowing all of us to participate and speak with our customers. As mentioned, STERIS is one of the organizations that did receive an emergency use authorization to decontaminate compatible N95 and N95-equivalent respirators. And that was using our V-PRO Low Temperature Sterilization Systems. Using vapor hydrogen peroxide process that we have established in our V-PRO sterilizers. And that EUA was granted to STERIS on April 9th and just to give everyone on the call a brief summary of the specifics that were included in the instructions for healthcare facilities, instructions for healthcare personnel, as well as the EUA, this allowed STERIS to provide our customers an option to decontaminate up to 10 compatible N95 and equivalent respirators using the non-lumen cycle of our V-PRO Low Temperature Sterilizer. And of that segment of V-PRO, that includes our models 1 Plus, maX and maX 2. Again that was 10, to decontaminate to 10 compatible respirators for a maximum of 10 cycles per respirator. 

Part of that requirement included both microbiocidal and functional testing as alluded to from my colleague at 3M that I'll talk to in just a few moments. Both of those testings were required to support the use of the cycle to decontaminate the N95 and equivalent respirators. And some of the methods, again at a very high level, that we included were using a surrogate virus that was more resistant than the coronavirus. And the results established at the end showed the use of the non-lumen cycle did achieve greater than or equal to 3-log reduction of the virus in the presence of soil without compromising the functional integrity of the respirators. And that's important to note that, it was in the presence of soil. Knowing that the respirators obviously would have some level of soil on them. It was important as part of the protocol and process that we showed a greater than or equal to 3-log reduction of the virus with soil actually being present on the respirators.  

That was really the facts of the EUA and the claims associated with it. I'm going to take just a few moments to discuss the background and really how STERIS and got there. Our goal in really looking at this whole process was to provide our customers, all healthcare professionals, with an evidence-based process to decontaminate the N95 respirators and most importantly using a method that they were accustomed to, and that was really within the four walls of their facilities. Making it easy for our customers to use a machine and a process that they use on a daily basis to allow them to begin decontaminating the respirators right away once the EUA was issued, and to make that process very simple for them. It was really at that point that my colleagues at STERIS R&D began investigating really the most appropriate and the efficient path to achieve this. In which we started with V-PRO as I've mentioned. 

And through that testing and the protocol development, STERIS did work with 3M and 3M evaluated the performance of the respirators. As my colleague just mentioned, really the fit and filtration of those masks after the reprocessing in the non-lumen cycle of the V-PRO as mentioned. As always with testing and claims, it's a good balance with lethality as well as compatibility. That was really the two-pronged approach that STERIS took in working with our R&D resources as well as our colleagues at 3M.  

Talking a little bit about what that process looked like, I'm sure everyone listening can appreciate this was a newer process for both STERIS and the FDA. Collaboration was crucial between the two organizations and that included a lot of discussion on the testing, the protocols, the strategy, revisions back and forth between the FDA and STERIS, which occurred for approximately two weeks. And in parallel, in preparation for the emergency use authorization, STERIS was creating several documents to help our healthcare professionals more or less successfully navigate through this process. Once the EUA was issued, we wanted to make sure that all of the I's were dotted and the T's were crossed to begin using this process immediately. And then we located those documents in our COVID-19 response landing page. That was the very high-level process of how it began with us evaluating the proper method to decontaminate the N95 respirators, to the point where the EUA was issued and all of the support documentations were available. 

In closing, obviously we're speaking about the specifics of the EUA and the process to get there, but I did want to mention, that there's also been a lot of effort to support the decontamination of the respirators outside the United States on a global perspective. And STERIS has used the EUA process really as the foundational pathway to provide similar solutions internationally. Similar to my colleague at 3M, I just want to thank everyone that is on the front line, breathing it every day. And I also want to thank my R&D colleagues for the tremendous amount of effort and time they put into ensuring that we had the EUA issued with a clear path for our customers. With that, I will turn it over to my colleagues at ASP. Thank you. 

ASP [Advanced Sterilization Products] 

Jeremy Yarwood (00:23:32) 

Thanks Chris. Good morning everyone. This is Jeremy Yarwood, vice president of R&D at ASP. My background is in microbiology and immunology and certainly a very incredible time that we're all living through. First I did not create separate slides. You'll see up in the upper left, they are linked to the ASP website where we provide materials related to the EUA and N95 reprocessing. And please do reference that for details on the process itself. 

In the meantime, I really wanted to provide some color and some perspectives on behalf of ASP as we think about this challenge. I do appreciate AAMI pulling together this discussion and allowing us to not only present our perspective but also to take questions and hopefully provide some additional guidance to users. 

First, I think it's important to say that that all of us hope this challenge goes away in the relatively near future. Certainly our perspective is hospitals and clinics should absolutely be going to every effort. They're taking every effort to provide fresh N95 and PPE to users and certainly as someone that has family members on the front line, this is absolutely the preferred option. At the same time, we know that hospitals and institutions, other clinics are going through a challenge right now in terms of being able to provide those and not only in the U.S. but globally. And so in the case where there is no other option, it was important that we provide the ability for users to decontaminate using existing STERRAD systems. 

Our investigation really started for two reasons. One is that we were fielding a large number of questions and inquiries from users in hospitals and clinics to say, "Is it possible to reprocess N95 in STERRAD systems?" And then two, FDA also reached out to us as I'm sure they did others on this call to ask whether we can validate systems for N95 reprocessing. My R&D team immediately began to investigate this. As has been mentioned, we work closely with 3M and other N95 manufacturers as part of this process. And frankly really do appreciate the collaboration that 3M and others have provided as we go through this process. Well, while we are experts in sterilization and infection control, we're not experts in filtration performance and N95 so the ability to have this very effective, very collaborative approach across industry I think is incredibly important to being able to provide the solutions that we have. 

In general, ASP has taken a fairly conservative approach. In addition to efficacy, which has been well established in our systems over many years and certainly effective against not only a range of viruses but more importantly spores which represent the most challenging organisms and certainly in the presence of soil have been shown to be effective. What was more critical for us is, again, to work with companies like 3M to assess functionality, form, and fit, and then the presence of residuals. I think as was alluded to previously, all gas- and vapor-based sterilization processes will leave at least a small amount of residual on the product after removing from the sterilization system. And N95 I should note are not typical medical devices. While we have incredible amount of biocompatibility and safety data on medical devices, again, N95 represents a somewhat different type of product. Part of our assessment was also to ensure that we could consistently allow the user to experience a peroxide residual of less than one PPM as an eight-hour time-weighted average, which is consistent with the NIOSH [National Institute for Occupational Safety and Health] and OSHA limits. And then also where appropriate, shorter-term exposure limits. Generally there's not a universal short-term exposure limit for peroxide, but where they are, regionally or within certain states, are generally in the range of two to five PPM over 15 to 30 minutes. 

All of those things were important for us to assess as we validated the process. In general, we were able to show that at least two reprocessings resulted in an N95 product that was still functional. In many cases, the data indicated that more reprocessings were possible. But again, given the newness of this type of process, given the potential variability of how users were wearing the mask, the potential damage to the mask over time, ASP took a fairly conservative approach in our recommendations. We also found that load configuration is important—how the masks are loaded into the sterilizer, how they're packaged. All of these things are important for the success of the process. And again, if you go to our website, you'll find the details of that process. 

As it was alluded to earlier, not all masks are created equal. We certainly have found that different providers, different manufacturers, even the different models within a manufacturer vary in terms of their performance. It's important to confirm the masks that can be reprocessed and certainly to confirm with the original manufacturer of those masks what processes they recommend. 

And then finally, I would say that we've rolled this out and provided guidance to users. One of the more frequent questions that we get is how to set up the process or workflow to manage N95 collection and reprocessing. And intentionally, and frankly, this was one of the discussions that we had probably more than any other with the FDA in a fair amount of back and forth. Certainly we want to allow institutions to be able to manage their own workflows as effectively as possible. And so how they collect and process masks could and should be highly dependent on that individual hospital’s or institution's practices. We've made some recommendations within the materials that were provided. At the same time, recognizing that hospital's workflow, literal structure, where they have the SPD versus OR for instance, will all influence exactly what these processes look like. And so we're certainly available to provide help and guidance throughout the setup of those processes. 

In closing, again, I want to thank certainly members of the hospitals who are realizing that the challenge these days is essentially unprecedented. We all learn, we all will support as best as possible, those on the front lines and certainly do anything that we can to provide additional input and guidance to users as they set up this type of process. Thank you to AAMI, thank you to 3M, and particularly those in the front line for everything they're doing to help provide an effective solution here.  


Peter Kalkbrenner (00:32:04) 

Thank you. So yes, from us too, thank you to AAMI for putting this together, a chance to share some knowledge and give some information to the front […inaudible 00:32:24] side, because without their support in this, we wouldn't have been able to get where we are today. They are the ones that provided the evaluation and testing as far as fit and filtration. And I also want to give a shout-out to my Sterilucent team here. We're kind of a small company. We don't have a lot of deployed units. We do make a vaporized hydrogen peroxide sterilizer. We do have FDA clearance on it. 

Just want to say a little bit about the timeline for this. We received our clearance on the 21st of April, it was 27 days before that where someone had this idea, "Hey, there's this critical shortage out there. What can we do to help assist?" And that kind of set off a scramble within our company. Like I said, we aren't very large, but at the time we didn't even have resources that knew specifically the difference between an N95 respirator and a surgical mask and a standard face mask. So, what are these things made of? What are existing decontamination methods? Can we do it in vaporized hydrogen peroxide? We certainly should be able to, and we just started doing some testing and some evaluation, started reaching out, trying to find sources for masks, and where do you go when there's something you need? eBay, pay the exorbitant prices but get them in house, do some testing. Started reaching out to 3M. People might be able to do testing, and results of that was finally getting our EUA. 

As one of the other presenters said, significant interaction with the FDA back and forth, interactive review. We used an outside consultant for our process for getting the clearance. We used established test protocols that we already had in house for the HC 80 tabletop sterilizer. For efficacy, we did sporicidal activity using the most resistant organism, vaporized hydrogen peroxide, that being Geobacillus stearothermophilus. And we showed a greater than 6-log reduction under half-cycle conditions. So we did that testing based both on the outside surface of the mask and on the inner surfaces of the mask. 

Exposed samples were submitted to 3M for the filter and filtration performance testing. We had exposed to two, five, and 10 cycles. Just we want to see where we were, if there was any degradation over time. 3M actually went and started doing the 10 cycle exposures, might as well. They're swamped supporting everybody in this effort and if it's good at 10, you can make it through two and five. But we had submitted two and five and 10 to them based on their request. And so they did the filtration and fit testing after 10 exposures. We originally did three mask models, the 1804, the 1860, and the 8210. 3M has additional samples there that we've exposed, and we're pending results on those.  

So then we applied for the FDA EUA. We had kicked off discussions with them prior, and then there was some back and forth finalizing the labeling instructions for healthcare users, etc. Within our HC 80TT sterilizers, the emergency use authorization, the usage is using the flexible cycle. There's two preprogram cycles on that sterilizer, the flexible and the lumen, the flexible being the shorter one. It's about a 35-minute cycle time. Our EUA allows up to 12 respirators per cycle, and each maybe processed up to 10 times. As with the other EUAs, at least for STERIS and ASP, it's single-user reuse, you need to maintain traceability to the user. You do that by labeling the mask prior to packaging and sterilizing. Likewise, reference respirators must be clean and undamaged. 

Documentation supporting that, the instructions for healthcare facilities, instructions for healthcare personnel, the fact sheet for healthcare personnel, those are all available on our website. They're also available on the FDA website. If you pull those up in the header, you'll see STERIS. That's not us. We're Sterilucent, we're the smaller company. And on our website you can get the documents with the correct title on them.  

One of the unique things about our cycle processing these, we have a dynamic delivery system that's talked about a little bit in our EUA letter, where we actually continuously measure the concentration of peroxide in the cycle, and we're finding with these lighter loads, these lighter masks, that dynamic system is scaling the amount of peroxide needed way back, still achieving the efficacy needed, resulting with lower residuals on the mask and lower cost to reprocess the masks, of course. So again, I want to thank 3M for helping support us in this testing. I'd like to especially thank all the frontline workers that are dialing in and listening to this presentation and we are available for any questions you have. And now I'll transition it off to Will at Battelle. 


Will Richter (00:37:57) 

My name is Will Richter, I'm a principal research scientist at Battelle. I have about 18 years of high containment, BSL3 experience here. And my background is specifically in biological decontamination. So at Battelle, to try and answer this question and problem of N95 shortage. We developed the Battelle critical care decontamination system, based on our background and knowledge of a vast number of fumigant, decontamination types and technologies. 

This problem first came across our desk in 2014/15 and we realized this could potentially be a problem or an issue that needed some real solutions. There were some initial research done that showed some areas of promise, other technologies that showed deleterious effects, and limited numbers of cycles. So the Institute of Medicine, when they did their paper exercise based on influenza pandemics, thought we needed around 50 repeat cycles to get us through a pandemic situation. So in 2015/16 we went to the FDA, acquired some funding through them, to begin looking at this problem. 

Again, based on our background of working in the high containment laboratory, we thought that vapor phase hydrogen peroxide would be a really good solution to potentially solve this problem while mitigating material effects. So we conducted a study and we looked for 50 repeat decon cycles. We inoculated these masks with the G stearothermophilus spores. I think being able to show that 6-log spore reduction is important, because we're not only interested in the current virus of interest, SARS-CoV-2 virus, but there's also other potential nosocomial pathogens in these environments that we don't want to inadvertently expose healthcare workers to as a result. 

So this study showed that we could, and again we were using the 3M 1860 initially for this study, but we showed that our process was good through 50 cycles with the filter media specifically. We never saw a reduction in filter efficiency on that mask. I think in most cases it was better than 99% collection efficiency through the full 50 cycles. And then we did a series of material tests and fit tests specifically looking at the head straps. And what we found is that between 20 and 30 cycles, we started to see a reduction in elasticity of the headband. 

So for our current CCDS system, we limit it to 20 cycles. And when we inoculated the spores onto the filter media, we did it in two ways because we also felt it was very important to show reduction of that agent through the full thickness of the mask. So we did two types of inoculations. We did a liquid droplet, a large liquid droplet to simulate a splash. We also did an aerosol inoculation to capture the spores internally within that 3D matrix, because most of these N95s are multilayered, and developed our cycle to be able to get a full decontamination throughout the entire thickness of that mask. 

So kind of stepping through the process, we did that study in 2016. March 6th through 22nd of this year as this sort of reached U.S. shores, we built our first CCDS system. Because we were going from a lab scale to a full deployed scale, we needed to again show that we could scale that process up and efficiently decontaminate the spores on the mask. So we reproduced that and then went to the FDA and got the EUA on March 29th.  

So then skipping forward a little bit to April 9th, the federal government awarded Battelle a contract where we can now provide this service free of cost to healthcare providers all across the country for, I believe it's up to six months from early April, April 9th. That included the development of 60 of the CCDS systems that we can rapidly deploy across the U.S., and I think we're around 15 or 20 regional sites that we've set up all across the U.S. So in addition to this rapid deployment, we have an R&D effort kind of ongoing to do those and to try and really round out the research as we go. 

We're very confident in our procedures, we know that we can thoroughly decontaminate these N95s off-gas and below one PPM, so that there's no exposure risk for the healthcare worker after they receive them. But the initial research was done with one type of mask. So we've gone back, we're looking, I think at 12 or 15 different types of N95s now, and we're through 15 to 20 repeated cycles with most of those. There have been no unfavorable results to date, so we still are maintaining that filter efficiency of greater than 95 and that fit test requirement. We have gone back into our BSL3 laboratory, and we've inoculated these masks with SARS-CoV-2 virus, and we have confirmed that we completely inactivate the target SARS virus on these masks, the virulent strain in the BL3.  

We are also working with some regional healthcare providers that asked a really good question. The initial study looked at decontamination. Then we did it in batches of 10, so we would do 10 cycles and then we would assess fit and aerosol resistance. We would do 10 more cycles and so on and so forth, but that use portion wasn't part of it. So we've gone back, partnered with some healthcare providers. They used the PPE, they put it through our decon process, and then we test it so it captures that used piece of it, from a soiling/sweat perspective. And we're through a couple of cycles currently, so we see no reduction in efficacy or performance. And we intend to keep building on that.  

So we developed a pretty robust process. We've to date deconned several hundred thousand pieces of PPE N95s. And to kind of go through the process first, I'll point you to the battelle.org website. We have lots of information, frequently asked questions, and it's your first point of contact if you are a healthcare system and you want to have this service, again at no cost to you. Go to that website and you can begin your enrollment process. So step two, we sign a contract with you. So even though it's free of charge, we need to have that in place before you can start sending PPE to us. And most critically, what that does is it assigns your healthcare system, your hospital, a three-digit unique code that can be expanded upon to a unit and to an individual if the healthcare systems so desires. And that three-digit code is unique to you in the country. So no other healthcare system in the country will have your unique code. 

So whether you're dealing with a regional site in your state, or potentially sending it to Ohio for processing, you can be assured that you're going to get your PPE back to your facility. So once you receive your three-digit code, we ask that you use a Sharpie and label that onto the front of each mask. And then at that point, you can start collecting your PPE into biohazardous bags. One thing to note is we can't accept any PPE that has gross contamination. So the biggest rejection rate has been due to the use of makeup. So we ask that there's no visible contaminants, whether it's blood, lipstick, or makeup on the N95.  

You collect those into a bag, double-bag that, decontaminate the outside of that second bag, place it into a box. That box has to have a biohazard indicator on it, and again, that three-digit hospital identification code. You then send that to our site. We receive it and we put it into our inventory system that is barcoded. It'll track it through the whole process. The PPE is taken out of the box into the decontamination chamber where staff in high levels of PPE will remove the respirators and inspect them. If there are any found with makeup or gross soiling or defect, they will be rejected. We count the number that are rejected. 

They're placed onto racks for decontamination. The decontamination process is implemented. Again, this is a condensing form of hydrogen peroxide vapor that gets applied. There's then an aeration period, and we can't reenter the chamber until we're below one PPM. Once we reenter the chamber, we can start sampling individual respirators to ensure that the N95s are below the one PPM threshold. It is then packaged up and sent back to your facility. Again, we believe this is a really good asset for the country, for the healthcare workers. If there are any questions, feel free to get ahold of me. I appreciate it. 


Are there any recommendations for further aeration of the decontaminated masks that have been received back, or where should end users look for guidance on further aeration? 00:50:11 

Will Richter/Battelle (00:50:27) 

One thing I'll note on that, to remove the PPE from our chamber, we have to be below the one PPM level. And in many cases, we're well below that one PPM level. There are certain pieces and parts, namely the foam and some of the nose pieces of certain PPE that can hold onto the peroxide a little longer. We have identified that and those become the target. So we have to record on our forms the highest reading of PPM that we see in the PPE. We've also packaged and left that on the shelf for a couple of days, gone back to it to make sure that as it's sitting in the repackaged bag and box that we're not artificially raising our PPM in process. And we found in practice that we're within a 10th of a PPM of when we clear it to when it's in the box for shooting it back. 

Jeremy Yarwood/ASP (00:51:34) 

We provided very specific recommendations to users in terms of aeration after removing from the STERRAD system. And following those recommendations, we consistently see one PPM or less and have confidence that the users and those that are exposed to the vapor will be in a range that's consistent with OSHA and NIOSH limits. Again, fairly conservative with that, trying to account for a range of different mass materials and products. But this was certainly an important consideration and again behind the aeration recommendations that we've made as part of our rollout here. 

Peter Kalkbrenner/Sterilucent (00:52:29) 

We likewise did pretty rigorous testing on those residuals that were in there and simulating worst case conditions might be expected, and that's what our aeration time is based on. Again, like everybody else, below one PPM at that timeframe following the aeration period that's in the instructions for healthcare users. 

Bill Brodbeck/STERIS (00:52:56) 

I would agree. We also have done extensive testing on this and show that the residual levels are definitely well below those that are acceptable, and we feel confident with our recommendation right now that after our cycle, our non-lumen cycle within the V-PRO sterilizers, that no further aeration is required. 

Why is microwave not recommended? (00:53:27) 

Jessica Hauge/3M (00:53:32) 

Based on available literature, microwave oven heating is not compatible with adhesives and metal parts, and a lot of filtering facepiece respirators do contain metal components, namely the nose clips, and also for some models the staples that attach the headbands to the cups of the respirators. And then of course a lot of filtering facepieces do also contain adhesive. We've seen that microwave energy can heat the metal components, which causes melting of the surrounding materials, which could potentially create pinholes and also distort the shape of the respirator body, which may result in it not being able to seal to the face the way it's designed to seal. And then also with the impact on the adhesive, if the microwave energy does melt the adhesive, the nose foams may not be attached the way they were intended to be and the nose foams may also become compressed or distorted, which could also compromise the fit of the respirator. 

We also received a number of questions about whether these emergency use authorizations can be extrapolated to other types of masks like the KN95 masks, valve respirators, a closed duckbill style of mask. Is there a list of compatible masks that folks should be looking for? (00:54:48) 

Will Richter/Battelle  (00:55:05) 

We've had a number of large healthcare systems across the country that have purchased large quantities of KN95s and have sent them to us for performance testing. We have found some that perform as labeled. We have found others that do not. So I believe that NIOSH has an approved list that are N95-like, so I would encourage any healthcare system that is entertaining those to go to the mask website and make sure that the KN95s that you are purchasing are on that list. 

Jessica Hauge/3M (00:55:56) 

From the 3M perspective, we want to make sure to emphasize that we are publishing lists of our respirator models that are compatible with HP [hydrogen peroxide] contamination method and so folks should refer to our technical bulletin on the topic for a list of models that are compatible. 

 We likely have some attendees in the audience who are considering going through the FDA process to develop emergency use authorizations. So for those of you, our panelists who've been through that, what tips do you have or what resources might you recommend to navigating that process? (00:56:19

Jeremy Yarwood/ASP (00:56:39) 

I think early and frequent engagement with the FDA is certainly critical here. Of course there's some precedent now for at least what some of these processes can look like and I think provide some parameters both for the FDA and for folks that might be filing for this. But as I'm sure again was the experience with some of the others on this phone, there was a lot of back and forth, a lot of conversation as both sides were navigating sort of uncharted territory, if you will. So to me, an effective and open channel with the FDA is the number one requirement, and then of course there is additional guidance that the FDA has issued over the past few weeks related to this crisis that is, of course, critical for the structure of the conversation and types of data to be presented. So certainly, if people haven't accessed that, I would recommend that they do that, again, certainly available on the FDA website as well as elsewhere. 

Peter Kalkbrenner/Sterilucent (00:57:47) 

I mentioned earlier we're a smaller company, and we actually used an outside consultant to help us with that regulatory process. But like the previous speaker just said, the FDA has published the guidance documents. Most of those have contact information in them too. So that's a place to start. Go to the FDA website, look at their recently published documents, use the contact information that's within those. 

Bill Brodbeck/STERIS (00:58:10) 

Definitely I would agree early, frequent communication with FDA. They've been fantastic to work with through this process. It was new to them as it was new to us to initiate the process and move forward with this, but they have been fantastic in terms of their communication. They've been working basically 24/7 trying to get some of these through and these authorized. So yeah, my recommendation would be definitely share with the FDA everything and anything you can as they try to ask more questions and help address them as well. 

Peter Kalkbrenner/Sterilucent (00:58:51) 

Yeah, kudos to the FDA. I have to agree. When they're reaching out to us on a Sunday at 11:00 PM to go through some more data, you know they're working around the clock on it. They know it's important, we know it's important.