Meet the UC Berkeley scientists using decontamination to tackle COVID-19’s PPE shortage

Five UC Berkeley scientists discuss how they’ve pivoted their research directions during the COVID-19 pandemic, and leveraged their expertise and training to write guidelines on safe PPE reuse using UV-C light exposure for decontamination
From left to right: Samantha Grist, PhD, Anjali Gopal, Alison Su, and Alisha M. Geldert from the Amy Herr lab (Photo credit: Gabriela Lomeli), and Halleh Balch, PhD, an alumna of the Feng Wang lab (Photo courtesy of Halleh Balch).

On Monday, March 16th, the UC Berkeley campus received the order to prepare to “shelter in place.” As a 2nd year PhD student in Professor Amy Herr’s lab, I joined my lab mates in ramping down all experiments and shutting our doors. While the lab may have been “closed,” our research efforts never stopped. By the following Monday, a large portion of our lab had joined the newly formed N95DECON team, a group of more than 100 scientists from 10+ institutions, whose aim is to share data-driven information about N95 respirator decontamination. Safe decontamination and reuse of PPE, such as N95 respirators, have the potential to alleviate some of the stress on the nation’s PPE supply due to the pandemic. Professor Herr, four of her lab members, and a recent alumna of Professor Feng Wang’s lab comprise the core UV-C decontamination subteam within N95DECON. Their work focuses on helping frontline healthcare workers safely and effectively use exposure with UV-C light—ultraviolet light with germicidal properties—as a method for N95 decontamination and reuse. I recently sat down with the core members of the UV-C team, who three months ago could not have imagined that they would so rapidly be pivoting their efforts to join the fight against COVID-19.

Gabriela: How did this team get involved with N95DECON?

Anjali: It was a week after the shutdown started. Our lab had organized a PPE collection drive to help funnel supplies to the frontline healthcare workers fighting COVID-19.

Samantha: That was on Friday, March 20th. The following Monday, our team joined N95DECON. The first set of decontamination guidelines for N95DECON were released April 1st. Looking at my calendar, I can’t believe those first documents were online just nine days from when we started. The first release of N95DECON was three fact sheets and three technical reports on the website ( Those first set of fact sheets were for three N95 decontamination approaches: UV-C, heat and humidity, and hydrogen peroxide.

Alison: I remember telling Amy that I was interested in doing COVID-19 response work after I had caught up on all my data analysis from data collected the past week (before “shelter in place”). And Amy replied, “Okay, great. Can you join now?” Little did I know that that was going to become what has been an absolutely incredible—but also just the most time-consuming—project and work that I’ve ever done in my life.

Gabriela: How have you leveraged your prior expertise towards these PPE decontamination efforts?

Halleh: My PhD studies were on optics and materials physics, within condensed matter physics, and I do optical spectroscopy. When I heard about Amy and the UV-C team’s work, I wondered if there might be an opportunity for me to use my training to contribute to N95DECON’s efforts.

Alisha: This is a unique and urgent time. When I started out, I would have thought, I don’t really have a medical background; I can’t really help that much. But these detailed characterization skills and understanding of the optics of how UV works and is measured are actually really important.

Halleh: One aspect of experimental science in general is that you are able to make accurate measurements and validate those measurements. That is a cornerstone of experimental science. That kind of training proves invaluable across disciplines.

Alison: A focus of Amy’s lab is always on bringing research questions back to the fundamentals: What’s governing the system? What equations can help you understand what’s happening at a fundamental level? Engaging in this kind of thinking has been a real benefit in my training because it sets you up to approach a problem that you’re not familiar with. That has been incredibly helpful in understanding a lot of the caveats that we’ve picked up with this complex, but perhaps seemingly simple UV-C technology.

Anjali: Another important aspect in terms of drawing in engineering principles is that Amy’s a big proponent of needs-finding, even in our research. That’s been the area that I’ve been more involved with in the group, talking to various stakeholders or hospitals or clinics and asking what it is they need in this type of crisis. Making sure we’re taking on initiatives that would be valuable to the people we’re trying to help is pretty important.

Gabriela: The global PPE shortage is a serious and urgent problem. This must be a busy time for you, as scientists working on this issue.

Alison: The last day I took off was my birthday in March.

Samantha: I took off the Sunday after that, and that’s the only day I’ve taken off since the shelter-in-place order began.

Alison: Pretty much every day was, or at least felt like, it was critical, and so it wasn’t just that there were deadlines or things to do. It was just this crazy time of knowing we’re in the midst of a pandemic, and we’re working on something that’s influencing the safety of others in the pandemic.

Halleh: The N95DECON group meets three days a week for an hour, and almost every single person on the call will participate in some format. There’s a lot of encouragement for individuals to contribute at every level and individuals are asked to contribute at every level. I think that it has made the organization as a whole, quite a unique endeavor.

Alison: Sometimes we’re doing kind of nitty gritty work on a call with 50 people, but, at the same time, what an incredible experience that, if one of us has concerns or doubts or thoughts, we feel free to express them, regardless of whether that person is an undergrad or a Nobel Laureate. That’s been really cool.

Samantha: We’ve been really grateful for the generosity of the experts in the field who’ve helped us to get there as well. Some of the key authors of the fundamental papers in this area have made time to speak with us to teach us about some of the fundamental concepts. Another example of this phenomenal generosity is a team at National Institute of Standards and Technology who worked with us to make a custom model of a UV-C exposure system and sensor to perform a ‘virtual calibration’ of a sensor that was not operating as expected, so that it could be used to more accurately measure UV-C dose.

Gabriela: Tell me about the collaboration with Frederick County.

Samantha: The group in Frederick County, Maryland is part of the Division of Utilities and Solid Waste Management of the county. They really stepped up to meet this urgent need of their local hospital in case they needed to implement this kind of UV-C-based decontamination. They quickly leveraged their expertise in water treatment, as well as their materials like their UV-C bulbs to build this really quite incredible system for decontamination. We spoke about their design, but more so on the importance of the UV-C dose and the validation of the dose.

Alison: Look at how cool engineering is that we can repurpose parts from a wastewater treatment system to meet such an urgent need!

Gabriela: What has been the hardest part of this experience?

Alison: The fact that we are in a pandemic. Hearing really heartbreaking stories from places that were running out of N95s. There was a day when a family member was in the hospital with COVID and I felt so helpless. Working on N95DECON was something I could do to feel like I was making an impact. Thankfully, that family member has since recovered and is back home.

Samantha: It’s hard when you don’t have the answers, when you can’t help. One of the experiences that has really highlighted that for me is giving a couple of webinars as part of N95DECON. One of the hardest things for me has been in some of the webinars when people ask questions like, I don’t have a UV-C sensor, what do I do? And you have to say, Then you can’t use UV-C. You don’t have a better answer for them. When using these UV-C sensors for decontamination, it’s very important that you use the right one. It’s very important to use it in the correct way. It’s very important that your UV-C sensor is actually UV-C specific, that it matches well with your UV-C light source, and that it has the right dynamic range and angular response. There are many intricacies to this measurement. Not being able to have a solution for someone, I think, has been the hardest part.

Gabriela: What has being part of N95DECON taught you?

Samantha: This crisis has highlighted for us the importance of the peer-reviewed literature and the role it plays in providing evidence to draw from to inform decisions in times of crisis. The highly variable quality of non-peer-reviewed preprints that exists also solidifies why peer review is so important. The other thing that was surprising for me is that you never know when a paper is going to be crucial. A lot of the sources that we cite, that form a key piece of our understanding, didn’t have hundreds of citations before this pandemic began and they weren’t in in journals with high impact factors. But these resources form such a critical piece of information for an urgent situation like this.

Alisha: I have been envisioning this whole experience as an internship in a way. One of my goals was to do an internship that was something translational, where I could apply my basic science and engineering knowledge to address a direct need. This experience fills a lot of those boxes of things I was looking for. I’ve gotten experience in how to communicate and collaborate with a much wider variety of people through speaking with police chiefs, medical workers in other countries, other researchers.

Samantha: I feel incredibly fortunate to have this kind of opportunity to work with such a phenomenal team, both this this smaller team here right now and then also the wider N95DECON group, to learn and solve problems, especially during this crisis.

As some labs restart in-person research and many of us look forward to ramping up our pre-shutdown experiments, the UV-C team knows their work is far from over. The team plans to use its increased access to lab to perform critical experiments to answer outstanding UV-C decontamination questions and keep contributing to N95DECON’s efforts.

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