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

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.

N95 Masks and Re-Use

Recent pandemic developments have strained the supply of N95 filtering facepiece respirators (FFRs), which protect users from particles and aerosols in the air that they breathe. Technically, they must filter out at least 95% of 0.3 micrometre particles.

Normally these are meant to be single-use devices, and are removed and disposed of in a secure way to prevent infection transmission. However, with supply shortages people are considering or resorting to re-using these FFRs, possibly with some sort of chemical or physical disinfection process. Disinfection processes are never 100% effective, so this is not a great option, but I guess it’s better than having no protection.

One disinfection method that I’m very familiar with is UV-C disinfection, having done research in the area of photochemical processes for several decades. There is published literature available demonstrating reasonable disinfection success for UV when applied to N95 FFRs, so this may be an approach to consider if necessary.

I’m working on an overview of this literature (draft version now available at this link), but I’m happy to consult (pro bono) with health care institutions that are considering UV applications to deal with their situations (


With the recent development of a viral pandemic, people are being reminded about the importance of handwashing for infection prevention. Coincidentally, in 2019 my colleague Prof. Marc Aucoin and I supervised a research study on handwashing for the CSA Group, a product standards organization. Specifically, our study aimed to determine if the faucet water flow rate had a significant effect on the ability of handwashing to remove bacteria from the skin.

You can access and read the full report on their website. The bottom line is that no, the water flow rate from the faucet didn’t have a significant effect over the range we tested, from 0.5 to 2.2 gallons per minute (about 2 to 8 litres per minute). Under all of those flow rates, on average about 99.3% of E. coli bacteria would be removed from the hands, which is good to know.

To do this study, we had to control all the other variables as much as possible, including the water temperature, and the amount and type of hand soap used by each person. The other big factor is the way that the hands were washed, including the length of time. For this study, we used a certain protocol from Public Health, and everyone involved in the study learned how to properly wash their hands. This was a good learning opportunity for people, including me, and so I reproduce the protocol that we used below. It’s a useful skill to know how to thoroughly wash your hands these days.

Recommended handwashing technique for infection prevention.

Graduation Rates Revisited

My blog statistics show that an old post from 2013 on Engineering Failure Rates continues to be a popular one to visit. There is an updated one available too, from 2018. As those blogs note, the data is from Ontario’s CUDO website and their definition of “success” is rather broad. If you start in Engineering, and graduate within 7 years from the SAME university with ANY degree, that counts as success for degree completion. So, if you start in Engineering then switch and graduate with a degree in Music, that’s success. However, if you start in Engineering, then leave before graduation to complete a Veterinary degree at Guelph, that’s not a successful degree completion for their statistics. So if you look at those statistics, you need to be aware of what they actually mean (or don’t mean)!

Those statistics always bothered me, so I came up with an alternative measure of Engineering graduation rates, using the same CUDO data source. My hypothesis is that if we use the Engineering first year registration data for a certain year, and then compare that with the Engineering “degrees conferred” data four years later, then that will give us a rough estimate of “success”, specifically within Engineering programs as a whole.

So that’s what I did with downloads from the CUDO website, with the admission data from 2006 to 2012, and the degrees conferred data from 2010 to 2017. (I used a 5 year comparison for Waterloo, since our program takes 5 years to complete when you include the co-op work experience. All other universities can be completed in 4 years, so I used that comparison for the rest.) Based on this approach, we can summarize the results in the graph below, showing average degree completion rates. The “error bars” show plus and minus one standard deviation of the average “success rates” for each university (a measure of how variable the results are).

I call the graph “apparent success rates” because it still doesn’t use individual student data; it’s based on bulk numbers that can hide a lot of variables. Indeed, as we gaze at the graph we see some obviously puzzling results. The Engineering programs at Windsor and Lakehead are highly successful at graduating more engineering students then they admit!

Clearly there are some problems with this data analysis. For one, it doesn’t take into account the fact that some students at other universities can do an optional co-op or internship that will delay their graduation by a year. Secondly, it is based on first year registration data for each engineering program. This means that the students who transfer into Engineering from other programs within the University, or from other universities, are not counted. Likely this explains the ones where the graduation/success rates are over 100%, and may be a factor for those who have rates approaching 100%.

I have no deep insights into the other universities, but for Waterloo I know that in my experience we have extremely few transfers from other Universities, and very few from other programs at Waterloo. Therefore the average success/graduation rate at Waterloo of around 78% is likely a reasonable ballpark estimate for the fraction of new admits that graduate in 5 years.

This all just illustrates once again that defining “success” is complicated, and getting meaningful data to measure “success” is even harder. We just have to make do with what we can get, and recognize the limitations of the data.

Applying to University: Done Your Homework Yet?

For those applying to university for Fall 2020 admission, there is some homework you should have done, or at least started by now. Arguably, this is probably the most important homework that you have, even if no one has explicitly assigned it or told you to do it. Properly done, this homework will make success in university more likely. So what is this homework?

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The Recycling Economy

Resource Recovery Partnership Conference

For the sixth year, I’ve been helping organize the “Resource Recovery Partnership” conference in collaboration with industry, government, and academic colleagues. This year’s event is on Thursday September 19, 2019, and registration is free for either in-person or webcast attendance. The final agenda is available, and anyone interested in the ideas behind sustainable materials, recycling, circular economy, zero waste, or materials and energy recovery might want to attend some of the webcast sessions. There are a range of speakers and panelists covering various aspects of policy development, technologies, and current statistics and trends. The talks are not highly technical, and anyone could benefit from some of the insights available here.

As our landfills (and oceans) fill with wastes, it has become clear to most people that solutions are needed to reduce wastes and to recover some value from the remaining waste materials. This is easier said than done, and requires a comprehensive approach incorporating technology, smart policies, economic drivers, and societal buy-in. These conferences have tried to bring together people from a wide range of backgrounds and interests, to try to advance progress in waste reduction. It’s a long and slow progress, but momentum seems to be building around the globe.

Campus Tours

Anyone considering applying to a university should visit it, if at all possible. Many people visit campus during the summer vacation period. This is convenient for travel, but not always the best time to get an impression, because most campuses are very quiet during the summer. Waterloo is a bit of an exception, since we have classes going throughout the summer for returning co-op students in engineering and other programs.

The fall is probably a better time for a visit, when things are more active and you can get a good feel for the campus in actual operation. Take a day or two off high-school classes and visit a campus! If you’ve never been on a campus visit try the closest one to home, even if you don’t intend to apply there. It’s good to get a practice visit so you know what to expect when you go to other places of more direct interest.

Of course, in some cases it’s not practical or financially feasible to visit a campus that you’re interested in. In that case, using online videos is one way to get a bit of a tour. I think that most universities have some sort of video tour availability. Here’s a recent video made by one of our own class of 1998 civil engineering alumni, Fanny Dunagan. It’s interesting to see what captured her attention when returning for a visit.

Enhanced Mobility Wheelchair wins first-place at the 2019 IDeA competition

A nice example of mechanical engineering students using their skills to solve real-world problems. See the link below for more details.

Five mechanical engineering students created the Enhanced Mobility Wheelchair for their 2019 capstone design project, and now their work is being nationally recognized for improving accessibility and inclusivity in Canada.

Wheelchair users often face challenges when deciding which device to use to get around. Regular wheelchairs are easy to manoeuvre, but hand-cycle wheelchairs offer better speed efficiency. The Enhanced Mobility Wheelchair team has designed and prototyped an augmented wheelchair that provides users with the comfort and maneuverability of a traditional wheelchair while offering the speed of a hand-cycle wheelchair. The novel drive system provides greater ergonomic support and promotes good posture even when the operator is tired. Selectable gear ratios greatly improve motion efficiency on a variety of terrain, helping those confined to a wheelchair go further and faster than ever before.

Source: Enhanced Mobility Wheelchair wins first-place at the 2019 IDeA competition | Waterloo Stories | University of Waterloo

HHT Awareness Month

Every day, week and month has a charitable or other cause associated with it. June is apparently Stroke Awareness Month in Canada, which is a good thing to be aware of because so many people are affected by stroke at some point, directly or otherwise. June is also HHT Awareness Month, although not many people have heard of it. That’s mainly because HHT is one of those less common conditions listed as a “rare disease” in the NIH GARD database and elsewhere. It is actually not technically that “rare” as it is believed to affect about 1 in 5,000 people, although possibly less than half of them know it.

HHT is Hereditary (i.e. genetic) Hemorrhagic (i.e. bleeding) Telangiectasia (i.e. small blood vessel malformations in the skin and mucosal linings), also known as Osler-Weber-Rendu Syndrome after the Canadian-German-French physicians who described it in more detail in the late nineteenth and early twentieth centuries.

The most common and noticeable symptom is frequent and spontaneous nosebleeds. Other complications include gastro-intestinal bleeding, chronic iron-deficiency anemia, stroke, heart and/or liver failure, and oxygen deficiency. The underlying reason is that a genetic mutation creates a problem with one of the proteins involved in blood vessel formation, leading to malformations in the skin, nose, liver, lungs, brain, intestines and elsewhere. This mutation is autosomal dominant, meaning that there is a 50% chance of passing it on to a child.

Although it is incurable, the symptoms and complications can be managed in a variety of ways, depending on the extent and degree of severity. There are HHT treatment centres scattered across North America and Europe, as listed on a website. The trick is recognizing that someone might have HHT, as many family physicians have never seen it and may not recognize the symptoms if they do see it. This is one reason why fewer than half know that they have it. Therefore the need for awareness, so that people can be diagnosed and treated before serious complications occur. In Ontario, there is an HHT Treatment Centre at St. Michael’s Hospital in Toronto (you need a referral from your family physician).

So if you or someone you know has frequent nosebleeds for no obvious reason, or unexplained iron-deficiency, check out the curehht website and consider following up with your physician, especially if it seems to run in the family.