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Flying Blind into January: Update on YorkU Air Quality [Oct 2021]

Flying Blind into January: Update on YorkU Air Quality [Oct 2021]

The "Return to Campus" Winter Term 2022 plan is outlined in this Oct 7, 2021 Senate document.[1]

It's Oct 8, 2021. Last week I heard from my Vice Dean of the plan to go back to in-person teaching in January, 2022.[1] I believe that this is potentially a premature decision as York University appears to have ignored deficiencies in its measures to fight COVID. These include a vaccination documentation system that may be compromised, an unaccountable, unenforceable and insufficient masking policy and incomplete ventilation defences. Here, I will address the issue of air quality and ventilation on campus.

I will begin by saying that COVID is airborne[2,6,7,8] and that it is imperative that we treat it as the workplace hazard that it is. We need to

  1. Block COVID from entering the air, and to
  2. Clean it from the air as soon as it does.

The first issue is addressed by high quality masking (N95+ respirators)[12,13] and keeping COVID carriers (asymptomatic and symptomatic) off campus. The second is addressed through bringing fresh outdoor air into our buildings, as well as purifying the air in each room using localized HEPA filters.[11, 14]

My understanding is that the last major official public update on the status of ventilation at York University was in May, 2021, with minor statements since. Since May, I've been in contact with Mr. Stewart Dankner, Director of Property Management at York to get further details about this very important topic.

Screenshots from York's September 2021 "return to campus" video. ( MERV 13 filters in our HVAC systems are good. But they're not enough.

Mr. Dankner has been gracious in his responses. I appreciate that and want to state that his work and the work of his employees is typically undervalued. I hope that we all now have a better sense for how valuable the work they do is. On September 17th, 2021 I again wrote to Mr. Dankner to receive some updates, asking four specific questions. The following are his answers to these questions:

1. Will we be able to get a room-by-room assessment of air quality on campus?  At the U of T they're providing estimates (modelled, not measured, apparently) on air change rates on a room by room basis ( 

We have not completed a room by room assessment.  We have reviewed the various buildings on both campuses and have reviewed the mechanical systems suppling [sic] air to each of them.  We have not documented our findings but have addressed any areas that don’t meet the ASHRAE and Toronto Public Health Guidelines, please see attached.  

2. Are there plans to monitor wastewater for traces of COVID?  This is being done on campuses like Waterloo and it has already been able to identify cases of spread. 

Not at this time.  We did attend a presentation on wastewater monitoring and decided that, at this time, the value of the information that would be gathered may not be beneficial.   We do dialogue with colleagues from other institutions to learn about the strengths and weaknesses of their programs.   

3. Would you consider making any realtime data on ventilation systems that your team has access to available on a public university website? 

Not at this time.  York University’s Facilities Services continues to monitor all systems for which optimal performance can support the health and safety of the campus. If and when issues are identified, they are investigated and rectified as quicky possible. In any case where systems issues posed a risk to space users, we would take steps to ensure their health and safety while the issue was being rectified.   

4. Would you consider posting any technical reports on the ventilation systems in a public way? 

Throughout the pandemic, we have consulted with external experts when and where necessary to ensure we adopting the best pandemic-control measures possible. We have not commissioned any independent technical reports at this time, as we do not think any of the systems that support classroom or research activity are of concern.  All are performing optimally.

My take-away from this is that we under under-measuring and under-reporting the quality of air on campus. We need to do better on measuring air quality, just as we should be putting serious consideration into wastewater[3] measurement of COVID (as McGill will now do), as it could help us figure out where and when outbreaks occur.

We need our employer to verify the air quality in all rooms on campus. We need to be verifying that all rooms, from classrooms and offices, to hallways and washrooms, from cafeterias to libraries can achieve six Air Changes per Hour through mechanical ventilation or six equivalent ACH (eACH) through mechanical ventilation plus air purification (HEPA filtration). This is illustrated here:

The "Clean Air Formula". We need to bring outdoor air into indoor spaces, we need to filter that indoor air and we need to verify that it's working. (Source:; 25 minute video overview.)

You need to measure to know it's working

This is a CO2 sensor is one way to measure air quality. It's inexpensive, unobtrusive and easy to use.

We need to verify that the air on campus is safe. We need to measure it and report it. Our faculty union, YUFA, has filed a letter to this effect on September 7, 2021. [9]

By verifying the air quality[4,15] throughout campus, community members will be in a better position to understand and mitigate against the risks of coming to campus. It will also provide the York administration with the data it needs to target priority areas on campus for ventilation upgrades. We'll know which rooms should not be occupied, and the degree to which it is safe to occupy the rooms on campus. It will also allow us to determine where we should install portable HEPA air purifiers while we await upgrades.

However, it's not sufficient for our air quality to be measured only once. We need continuous measurement and public reporting. That status of the ventilation of our buildings and in the individual rooms in our buildings need to be assessed on a regular basis and those values need to be provided to community members, as shown in this example in movie theatres. Air quality sensors should be installed throughout campus. They should be visible in most rooms. They should report their data, in real time, to an internet dashboard so that community members can know about the air quality before coming to campus. The positive effects of updating our ventilation systems[5] will go far beyond COVID.


We need to do more to make the air on campus safe. As Engineers Canada puts it: we need to be "progressive and proactive" about this. Let's build on the already good upgrades by measuring the air quality, room by room, throughout campus. Let's make those numbers public, and let's continue to measure and publish air quality data on an ongoing basis. And let's target deficient (and dangerous) rooms for appropriate upgrades so that we can all be safe while on campus.

James Andrew Smith is Professional Engineer and an associate professor in Electrical Engineering and Computer Science Department in York University's Lassonde School. Originally from Québec, James has degrees in Electrical Engineering from the University of Alberta and a PhD in Mechanical Engineering from McGill. He did a post-doc from 2006-2008 at the Institute for Sports Science in Jena, Germany. His engineering research background includes galloping robots, human birth and clothing. James believes that we can improve the way we teach. He 2018-19, he lived in Strasbourg and taught at the INSA Strasbourg (France) and Hochschule Karlsruhe (Germany) while on sabbatical with his wife and kids. Some of his other blog posts discuss the family's sabbatical year, from both personal and professional perspectives.

References / Links

[1] Senate plan for "return to campus"

[2] A list of airborne review studies.

[3] Forbes article describing the use of wastewater monitoring.

[4] NYTimes article on portable CO2 sensors in schools.

[5] Star article related to ventilation & Dr. Siegel at U of T.

[6] Collaborative on Health and the Environment "Delta and Reducing Airborne Transmission in Schools" webinar with Dr. Kimberly Prather, Dr. Dustin Poppendieck and Mr. Jim Roshenthal. Oct 7, 2021.

[7] Airborne transmission of SARS-CoV-2 by Prather et al in Science, 16 Oct, 2020.

[8] How did we get here: what are droplets and aerosols and how far do they go? A historical perspective on the transmission of respiratory infectious disease by Randall, Ewing, Marr, Jimenez and Bourouiba in The Royal Society's Interface Focus (related Twitter thread)

[9] YUFA open letter about ventilation, N95 masking / PPE, etc. [Sept 7, 2021].

[10] List of papers describing how COVID is airborne (among others) [Oct 17, 2021]

[11] Globe and Mail article: BC doctors call for improved airflow in buildings and strong mask mandates [Oct 20, 2021]

[12] Consumer Reports mask recommendations (spoiler alert: N95). [Oct 14, 2021]

[13] CIDRAP Commentary on What can masks do? (Part 1; Oct 14, 2021) : key image. (related thread)

[14] Mitigating COVID-19 in Public Spaces (ASHRAE Journal, Oct 2021): (thread)

[15] Dustin Poppendieck, "Uncertainty in using CO2 for ventilation clues in Classrooms.", Nov 4, 2021 (thread summary & original thread)