Results of testing for Macdonald-Stewart

Published: 17 February 2023

Dear members of the Macdonald campus community,

Late yesterday afternoon, we received the final results of the microvac testing in the Macdonald-Stewart Building, which has been underway since February 3, 2023. These tests provide reasonably complete information about this building, though we are still gathering information about Barton and Raymond.

Below in this email, you will find:

  • Results of the testing performed after the Macdonald-Stewart Building was closed
  • Resources for additional information and support, including a new FAQ
  • Information about next steps

Results of testing performed after Macdonald-Stewart (MS) was closed

Air tests (conducted February 1-2, 2023)

  • All 17 test results were compliant with the regulatory threshold

Round 1 of tests on dust samples (conducted February 3, 2023)

  • 10 out of 41 samples tested positive, mostly in hallways and other traffic areas, with two in specific rooms (e.g. labs, offices)

Round 2 of tests on dust samples collected from every room in MS (February 7-14, 2023)

  • 22 of 308 samples tested positive (18 in closed rooms, 4 in halls or staircases)

For Round 1 and Round 2, dust was gathered from multiple surfaces in the room. The samples were then sent to an independent laboratory for analysis using transmission electron microscopy (TEM). The laboratory then reported whether asbestos was present or not present in the dust.

This method of testing does not provide any information as to levels of asbestos in the dust or levels in a given room. Therefore, the fact that chrysotile asbestos is present in the dust tested does not necessarily indicate that there ever was enough airborne asbestos to exceed regulatory thresholds.

We began reaching out this morning to the primary occupants of the 20 offices and laboratories in which dust samples were collected that contained asbestos.

Resources for additional information and support

  • FAQs: We have created a page with answers to some of the questions we have been hearing, either through email or in person.
    • We know that we are only beginning to answer the questions you have. This page will continue to be updated over the coming weeks.
    • In the FAQs, you can find information about, for example, risks of health problems associated with asbestos; answers to common questions about courses, graduate work and research; and background on different types of testing for the presence of asbestos.
  • A Town Hall will also be held in the near future, so that people will have an opportunity to ask questions and request further information.
  • Resources for support: Given the limited information available so far, it is currently difficult to assess potential health risks, and I understand that this uncertainty could create anxiety. Whether you are a staff member of a student, resources for support are available. Please reach out if you feel upset or are struggling.

Steps and timeline for re-opening Macdonald-Stewart

First, we will ensure that spaces where dust that tested positive was found are thoroughly cleaned under specialty asbestos protocols.

Next, we will perform air testing again to ensure that cleaning has been successful.

The most optimistic timeline for the re-opening of the Macdonald-Stewart Building (Phase 1) is the week of March 6th. The timeline could extend for a week or two, depending on the availability of external firms who specialize in cleaning under asbestos protocols and the results of post-cleaning air testing.

To speed along the process, we will proceed in two phases. Please consult our FAQs to find information about the phases.

We will also hold a Town Hall around re-opening to answer questions from the community.

We recognize that this is a stressful situation for many, whether you are worried about when you will be able to access the buildings, are concerned about the impact on your year, or have questions about potential health impacts. It is a frustrating and uncertain situation, with longer-than-anticipated timelines. We are working very diligently to ensure a safe re-opening.


Pierre Barbarie

Senior Director, Campus Public Safety, on behalf of the Emergency Operations Centre (EOC)

Back to top