Monthly Archives: April 2020

Engineering Risk and Pandemics

While I have not posted often to this site, I have been thinking about parallels between engineering risk and risk to our health and medical systems due to pandemics (such as the one we are experiencing now) and so felt it would be useful to discuss.

Some years ago I had met the president of a wonderful and helpful organization, Engineering for World Health (https://www.ewh.org/) at a conference in California, and she told me about the severe lack of technicians and spare parts and anyone who knows how to properly maintain and calibrate medical equipment in the countries where EWH has ongoing projects. It seems to me the problem is universal, especially exacerbated by the current global crisis. In my Learning from Engineering Disaster course I emphasize throughout that engineering risk is proportional not just to likelihood of failure — as determined by history or mathematical models — but also to the human and financial cost of failure multiplied by the vulnerability of the system — which itself is greatly increased by ‘extreme conditions’. The Titanic would not have sunk when it did had they not been sailing in very cold water which made its rivets brittle (helped along by the use of an alloy susceptible to embrittlement). Likewise we have the case of the shuttle Challenger explosion occurring due in part unusually cold weather causing loss of elasticity to elastomer O-rings in the solid rocket boosters, the failure of the hurricane protection system in New Orleans exposed by a direct hit by a category 3 hurricane, etc. The Coronavirus pandemic is the ‘extreme condition’ revealing the limitations and flaws in our healthcare system, and it also magnifies the flaws and drawbacks in medical equipment.

Here are a few articles and news items I have found which I feel are quite relevant to concerns with current critical medical equipment:

https://www.apsf.org/article/ventilator-failure-in-the-icu-deja-vu-all-over-again/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3214584/
https://apnews.com/5f0b62d117e6f1646461c647a144a5da

and iFixit is a web resource crowd-sourcing repair manuals for medical equipment: https://www.ifixit.com/News/36354/help-us-crowdsource-repair-information-for-hospital-equipment

I don’t yet have a report describing shortages in medical equipment repair technicians — but there likely has not been time to write one in this crisis!

Here is one last connection to engineering failure to leave you with. The engineering risk equations I use to illustrate key factors in class is, in its full form:

Risk = (probability of failure x vulnerability x cost of failure)/mitigation

Clearly, mitigation is critical! In engineering that includes redundancy, failsafe systems, improved maintenance, etc. In the case of the pandemic, it is what is being drilled into us — social distancing, staying out of stores, etc. Reminds me of safety rules for working around radiation (another invisible, undetectable enemy!) — We use the acronym ALARA (As Low As Reasonably Achievable). It means spend as little time in exposure as possible, shorten the time of exposure, and use shielding or barriers. Sounds like good advice here as well.

Hence it might be valuable to consider how we might leverage the ways in which we view engineering risks as we consider other important risks (to our health, our health care systems, and also to the health of our planet — flora, fauna, and climate). Indeed, the computer models used to understand the peak spread, rate of infection and so forth for pandemics use many of the same models we could apply to failure in engineered systems. This includes risk to our financial markets as well — I just saw a news story in which an economists discussed the possibility of a ‘bath-tub’ curve applied to failure of the financial markets, something quite familiar to all forensic engineers and designers. The cross-pollination of knowledge among engineering, health, sociological, scientific and financial fields seems to be critical to inform our understanding of future potential crises and should be considered as we look for answers.