of a straw man regarding some newer BPI tech's reported non-ozone producing capabilities.
That being said, I'm generally in agreement w/ what's stated here. BPI manufacturers have historically touted their tech as a means for reducing ventilation rates, despite evidence... 2/
W/ the advent of the pandemic, they've now pivoted to focus on their tech's ability to control pathogens - a strategy that seems to have been pretty lucrative for some manufacturers/distributors. 3/
Even if this tech is being employed in a manner that maintains higher ventilation rates, many of the concerns listed here are still valid. Additional concerns include a) unknown impacts on human health from chronic, long term exposure & how that varies by demographic... 4/
factors like age, b) unknown short/long term impacts on the built environment's microbiome (it kills indiscriminately), & c) inadequate field testing of the newer tech to verify ozone isn't a byproduct at unsafe levels (lab tests aren't enough).
More research is needed... 5/
& as a strategy it should be low on the list of options to reach for, potentially limited to some high risk situations where other strategies aren't possible or adequate. If used, it should also likely be set up for on-demand use & not on all the time. 6/
But ventilation & filtration should always be the 1st strategies examined for improving IAQ & controlling pathogens.
Districts, universities, municipalities & other building owners need to carefully consider the risks associated w/ BPI before using.
Our new office policy we're finalizing essentially takes this viewpoint. In 3 of our offices, we've assessed high vaxx rates combined w/ addressing the Delta far field risk via ventilation/filtration is adequate enough for vaxxed employees (almost 100%) to go sans masks. 1/
Even in metro areas currently deemed by the CDC as having high or substantial community transmission.
To have vaxxed employees go sans masks in our other 2 offices, relative to their current lower office vaxx rates, the Delta far field risk needs to be addressed through... 2/
some combination of additional ventilation/filtration improvements, increasing vaxx rates, setting lower occupancy limits, or having non-vaxxed employees WFH - we are still assessing the best path forward for each of those locations.
. That we haven't had more districts close for a period of time is pretty fortunate considering everything. 2/
That we're still arguing over the basics of how to respond to a pandemic driven by a predominantly airborne virus demonstrates a multi-level failure of public health & government, exacerbated by a history of underfunding public health, public education, current levels of... 3/
A few questions for the UV specialists. 1st, are the studies/modeling that have been done so far relative to Far UVC impacts on eyes/skin sufficient to answer questions regarding a) potential negative impacts from chronic (continuous or repeated) exposure,... 1/
b) age/developmental specific concerns related to short term or chronic exposure, & c) concerns for those w/ pre-existing eye/skin conditions after experiencing short term or chronic exposure?
2nd, have studies been done looking at the impacts on the built environment's... 2/
microbiome, & the subsequent impacts on human health? And for this 2nd question, not just relative to Far UVC, but also for more traditional upper room UVGI systems.
Manufacturers are already marketing fixtures exposing occupants to Far UVC. Do the answers to either of the... 3/
This is an all hands on deck moment. In-person school is starting. W/ the #DeltaVariant, even w/ the majority of the relevant strategies in place, it’s going to be difficult to prevent transmission in our schools (linkedin.com/pulse/in-perso…). 🧵1/
In an elementary classroom w/ unvaxxed students, generally ASHRAE compliant ventilation/filtration, the addition of (1) portable HEPA filter unit, & theoretical 100% mask wearing (double layer cloth mask), max exposure is only about 1.2 hrs before an additional student... 2/
is potentially infected at full occupancy (assuming 1 infected student is present).
Accounting for the potential reality of younger kids not always effectively wearing their masks (50% mask wearing), the max exposure is under an hour before an additional student is infected. 3/
These are the type of actions our pharmacies, hair salons, retail stores, offices, universities, k-12 schools, individual residences, etc., need to be taking, particularly w/... 1/
a more transmissible strain spreading in the U.S. & months left before vaccination levels are where needed to be.
CO2 levels can be used to estimate ventilation levels, though it's important to account for factors like the number of people present, the size of,... 2/
the space, & the use of portable air cleaners. Pages 23-24 of this document from @HarvardChanSPH & @j_g_allen provide a means for estimating ventilation rates based on measured CO2 levels. 3/
I would challenge your point that “No matter what we do, resources will remain scarce and people will compete over them.” First, there’s an abundance of evidence from the archaeological, historical, & contemporary ethnographic records of individuals & groups cooperating... 1/
(employing some or all of Ostrom’s principles) to survive in environments of scarce resources (& not just hunter/gatherer groups). Not saying the evidence for competition (including violent competition) isn’t also there, or that the competition between groups isn’t also... 2/
what often drives the cooperation among group members (because it does), only that cooperation seems to have been most effective when these principles are applied (even as part of a larger competition between groups).