UV Disinfection Confusion

The pandemic situation has generated a lot of interest and activity in UV disinfection, which has been keeping me busy. Whether it’s for masks, air, surfaces or whatever, there are lots of things getting posted and promoted for using UV. There seem to be an overwhelming number of devices and designs being suggested or sold online. Unfortunately there are also a lot of misconceptions, errors and possibly fraudulent claims being promoted. I’m not going to try and address each and every device (there are too many!), but I can provide some basic ideas that one should know or ask about when considering UV devices. If the supplier can’t readily provide answers or details, then something is possibly wrong. Here are a few key confusing points:

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Classroom Air Cleaners?

Schools of all sorts are looking for ways to re-open while minimizing coronavirus transmission risks. Harvard University’s School of Public Health recently issued a downloadable document on “Schools for Health”. In it they suggest a number of administrative and engineering approaches for reducing virus transmission in a classroom and school setting. It’s interesting and worth a look.

Photo by Pixabay on Pexels.com

Since I teach and do research in some aspects of HVAC (Heating Ventilation and Air Conditioning) and indoor air quality, those parts of the report caught my attention. They are suggesting that people consider using portable air cleaners in the classroom, especially in situations where the HVAC is non-existent or poor. They don’t give a lot of numerical detail behind that recommendation, but it’s fairly easy to work it out. So I’ve done some quick calculations to see where air cleaners might be useful from a more quantitative perspective.

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Do Face Masks Work?

“Plus ça change, plus c’est la même chose” (the more things change, the more they continue to be the same thing, attributed to Jean-Baptiste Karr).

Introduction to an article from the Journal of the American Medical Association, January 12, 1918

In our current pandemic situation there has been lots of confusion, uncertainty and general ignorance on the subject of face masks and reduction of disease transmission. In the screen capture I show the introductory paragraphs of an article published over one century ago, just as the so-called “Spanish Flu” H1N1 pandemic was probably starting but not yet recognized.

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Defer University?

With the pandemic situation and the move to online classes by many universities, there is discussion about whether to defer starting university until 2021. This is a complex and significant decision, and an engineer (or prospective engineer) would typically use some sort of decision-making strategy. I’ve written about one decision approach, the Kepner-Tregoe method, in the past with respect to choosing a university. For the decision to defer starting university, let’s try a cost-benefit analysis method.

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Coronavirus drifts through the air in microscopic droplets – here’s the science of infectious aerosols

Here’s a nice summary article about aerosol viral transmission, by a mechanical engineering professor.  The physics of aerosols is a foundational concept in air pollution control.

Aerosols are the tiny particles of liquid and material that float around in our environment. When they come from an infected person, they may be a significant source of coronavirus transmission.

Source: Coronavirus drifts through the air in microscopic droplets – here’s the science of infectious aerosols

The Future of Chemical Engineering

Sometimes I see people getting concerned about future prospects for chemical engineering careers, usually because of some downturn in the oil and gas markets. I guess we should never stop emphasizing that chemical engineering is much more than oil, gas, and petrochemicals! There is also food, pharmaceuticals, alternative energy, environment, safety, consumer products, plastics, minerals, metals, paper & fibers, etc….

Actually, the next 30 years is probably going to be a very exciting and technically challenging time to be a chemical engineer. The world needs people with the innovation skills to handle new materials and energy processes more than ever. Why is that? Here are a few quick thoughts…

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Meet The Chemical Engineer Who Accidentally Turned Into An Entrepreneur And Just Raised $36 Million For His App

An interesting story below about an engineer using his observations in water treatment to innovate and improve work-flow for lots of other companies. A chemical engineering education can lead in lots of different directions!

In 2014, freshly graduated UC Berkeley alum Ryan Chan was working as a chemical engineer at a water purification plant, when he realized that the company was constantly facing equipment downtime. The workers used a maintenance program that helped them track all the breakdowns, but there was a big problem with the software they were using that was slowing them down.

“Everything was desktop based, but the maintenance team, the people that were using it, never sat at a desk,” Chan says. 

So Chan realized there had to be a smarter, mobile-first solution for all the blue collar workers across facilities. He wound up teaching himself how to code at night and on weekends, and developed the app while he worked as a chemical engineer, and later as an iOS developer.

In 2016, Chan launched UpKeep, an app developed for facility managers and maintenance workers that allows them to flag things that need repairs and run equipment audits across facilities.

Source: Meet The Chemical Engineer Who Accidentally Turned Into An Entrepreneur And Just Raised $36 Million For His App

Hand Sanitizer Blending

Photo by Anna Shvets on Pexels.com

Soap and water is a preferred choice for hand hygiene and reducing microbial and viral contamination. However this isn’t always convenient or available when out walking or shopping for necessities, so the next best thing is a hand sanitizer formulation. The nice commercial ones are in short supply, but it is relatively easy to blend your own if you can access the ingredients. Blending chemicals safely is another chemical engineering specialty. Here’s a recipe for small volumes for home use, with some discussion on the physical chemistry basis for the various components.

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Chemical Engineers and Pandemics

Chemical Engineering: the art and science of creating and operating industrial scale systems for transforming raw materials into useful products.

Photo by Gustavo Fring on Pexels.com

When “chemical engineering” is mentioned, many people think of chemical plants, refineries, and such. That’s one part of it, but it also encompasses many other things, including pharmaceuticals and vaccine manufacture. These days, everyone is talking about and hoping for a vaccine for Covid-19. What does this mean for some chemical engineers and what they need to do?

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Online Teaching Experience

The last two weeks of our lectures for the Winter term (last two weeks of March) were all done “online”, since the on-campus activities were shut down. This was an interesting experience, especially since we only had a week to prepare. It took quite a few hours of effort to figure out the online technology and work out different ideas and approaches before starting.

For my Air Pollution Control course, I used Webex to deliver the last two weeks of lectures live, sort of like some Webinars I’ve done in the past. These lectures were also recorded so that students who couldn’t attend “live” could look at them later. I liked the live aspect, so that students could submit questions via the chat function as we went along. I think that the ability to ask and answer questions is important, and you lose something when it can’t be spontaneous.

Luckily for me, the last two weeks of material in my course was relatively easy to adapt for online delivery. It was largely descriptive, not so much mathematical or technical. Some things that I would have normally done on the board in a classroom I had to adapt into a powerpoint deck, but it wasn’t too bad.

Delivering a whole course online is another matter, which my colleagues are scrambling to do for the term starting in May. Doing it really well takes substantial development work and a pedagogical re-think of virtually everything about the course. From what I’ve read, properly developing a truly excellent online course can take many months of preparation, audio/video recording, and editing.

Unfortunately we haven’t had a lot of time to do this, but our instructors seem to be seriously working on it as best as they can. I don’t have any courses to teach in the May-August term, but I’m keeping a close eye on how it’s done in case we are still teaching online in September when I teach another course. The university has developed a website where we can find some suggestions and other resources for online teaching. I hope we can have classroom teaching again in September, but there are some doubts and I guess we have to be prepared for anything at this stage.