Ontario Professional Engineers working in building facilities management, especially but not limited to public buildings with known poor ventilation such as schools: ASHRAE unequivocally states #COVIDisAirborne. There is a Duty to Report involving safety. /1
When the reckoning comes regarding failure to prevent #airborne transmission of SARS-CoV-2, Professional Engineers should be on the right side of history. Continue to follow the Professional Practice Guideline. @PEO_HQ@O_S_P_E /2
Engineers need to go on record with their employer when they have identified a safety concern. They may have limited options to affect change, but they do have a duty to report it up the chain of responsibility. Write that memo. Come away with a clear conscious. /3
JULY 26, 2021—Ontario Society of Professional Engineers @O_S_P_E calls upon @Sflecce & @ONgov to immediately consult with subject matter experts and address #airborne transmission in schools before more outbreaks occur: ospe.on.ca/advocacy/engin… /1
"Engineers know if we are going to combat the Delta and future variants and a potential fourth wave, the need for proper ventilation and filtration of indoor air is paramount" says @O_S_P_E. /2
"Engineers know that air quality is bigger than COVID-19" says @O_S_P_E.
"The cost of investment is small compared to the benefits we will reap in finance, health and wellness" /3
1/ Oh hai Clinical Excellence Commission @NSWCEC. Looks like you wrote an IPAC Manual for Quarantine Hotels recommending air pressure differential limits without considering the implications. Would you like some assistance with that? THREAD...
2/ Allow me to introduce you to Bernoulli's Equation as it pertains to flow through an orifice. In this case, under and around a door.
3/ Bernoulli's equation allows us to predict airflow from a pressure difference, and vice-versa. The Florida Energy Center tested various orifices for flow & pressure difference. ba-pirc.org/casestud/retur… Using these results I calculate a Cd of 0.71 for various slots.
1/ Dental office #COVIDCO2. The perfectly operable window is closed. 🤦♂️ THREAD...
2/ At the end of my visit, in a 144 sqft room with 9' ceilings, the hygienist and myself, it reached 1500 ppm. Overall rebreathed fraction of air from others reached 2.8%. The door to the operatory was open 1 inch.
3/ I believe this is the outdoor air intake for the whole building. Located behind two air conditioner outdoor units.
1/ The Delta Fredericton has central corridor air pressurization and shared washroom exhaust. Lower floors may have inadequate pressure allowing air to flow out of suites. Failure of an exhaust fan can lead to direct connection between all suites on same shaft, @ShiftNB
2/ This style of ventilation & exhaust is disproportionally prevalent in Ontario apartment building outbreaks. Before concluding fomite transmission a more detailed analysis by subject matter experts (building science) is required. @DFisman@IPACCanadadocs.google.com/spreadsheets/d…
3/ More detail about the possible mechanisms from building science in this thread:
1/ Public Health @cityofhamilton, to stamp this out fast, you should issue an order requiring off-site air-gapped isolation/quarantine accommodation for those with an active infection. cbc.ca/news/canada/ha…
2/ Off-site air-gapped isolation can take the form of individual trailers, or a newer hotel that has been tested for dwelling unit compartmentalization.
3/ We know from decades of building science that there is significant unintentional air transfer between suites, especially in older buildings.
#Onted, who would be able to provide data on number of classrooms, students per classroom etc for Ontario so that I can do some capital cost and operational costs on air quality related upgrades? More than the 2015 facility condition list. edu.gov.on.ca/eng/parents/fc…
2/ I'm thinking of some per-classroom budget numbers balancing operable windows/fan, HRV, filtration, upper room UVGI, including energy costs/penalty, GHG emissions, maintenance.
3/ I can do analysis per classroom with an "average" class size or some distribution bins and then multiply through by total classrooms to arrive at a total $ figure.