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.
4/ Other notes: There is a 99 CFM CADR air cleaner in the operatory. It was running on low speed. After discussing with hygienist, she turned it to full speed. This provides 4.5 ACH of equivalent ventilation for aerosol removal.
5/ Hygienist was contact + droplet protection. Double-masking surgical masks. No N95s unless AGP, as per Royal College of Dental Surgeons of Ontario.
This is guidance still as of MAY 2021.
THERE ARE AMPLE SUPPLIES! @BarryHunt008
*BREATHING* IS AN AEROSOL GENERATING ACTIVITY!
6/ I mentioned I can wear my (vertical-fold style) N95 all day without any issue, it's more comfortable than the earloops-style surgical masks.
Hygienist said her N95 (rigid cup style) has to be pulled really tight against her face to get a passing fit.
7/ @rcdso_org, how do you reconcile "put safety first", "prioritize caution and safety" while also placing inventory of PPE of high importance?
8/ @rcdso_org, you had an opportunity to improve protection from respiratory aerosols in line with Health Canada & CDC documentation, and CSA Z94.4-18. But last week (May 19 2021) all you did was add gowns. Gowns.
9/ No change from 6 months ago. I sent the appropriate information by email, tried following up.
🦗🦗🦗
Front line staff are very interested though. As one would be when "working inside a sneeze all day" as @dentalhygieneq1 says.
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.
1/ HOW TO HIDE YOUR DATA
In the highlighted section from Conly's presentation last month he references no transmission events in 5544 person-hours.
Source is "Conly J et al ARIC". Here's the section of that reference: (aricjournal.biomedcentral.com/articles/10.11…) H/T @jmcrookston@CPita3
WHO's pandemic guidance language for health care workers regarding proper PPE is belittling and paternalistic on matters of workplace safety.
This language is like when construction workers chastise peers for wearing PPE because they think it's a sign of weakness.
Reminder once again of the fallacy of the "AGP" (aerosol generating procedure). Regular activities produce FAR MORE bioaerosols than specific medical procedures.
1/ I wear an N95 at locations outside of my home. I wear it to the grocery store, pharmacy and my doctor's office.
It's comfortable, doesn't hurt my ears, doesn't fog up my glasses, and easy to breathe through. I can wear it all day, anywhere. EXCEPT at the hospital!
2/ Many health care facilities require visitors to REMOVE their superior respiratory PPE and don a basic surgical ASTM Level 1 mask.
This practice must stop.
3/ Here's my friend Annamaria's experience this past Thursday when she went to @NGHSimcoe for her second vaccination, shared with her permission👇