David Elfstrom 🍁
@davidelfstrom.bsky.social
P.Eng, Energy management, measurement & verification. Toronto, Canada. Born 327ppm CO2. Climate Action & electrification; Safer infrastructure; cycling; air filtration & ventilation
Happy New Year, pocket pals!
Happy New Year phone friends!
January 1, 2026 at 4:27 PM
Happy New Year, pocket pals!
Reposted by David Elfstrom 🍁
Hey Canadians, if you followed storm chaser Mark Robinson from the Weather Network on the bad place, he's here too. He doesn't post much, but maybe we can get him to if we flood him with follows! @stormhunter.bsky.social
December 29, 2025 at 6:19 PM
Hey Canadians, if you followed storm chaser Mark Robinson from the Weather Network on the bad place, he's here too. He doesn't post much, but maybe we can get him to if we flood him with follows! @stormhunter.bsky.social
Reposted by David Elfstrom 🍁
Whenever I see a surgical mask in use, I engage in conversation. Even if its a doctor at a hospital.
Many honestly are not educated in airborne pathogen prevention....yet.
A hindrance to switching from surgical to N95/respirator is cost unfortunately😔
Thanks to @donatemask.bsky.social there is a way
Many honestly are not educated in airborne pathogen prevention....yet.
A hindrance to switching from surgical to N95/respirator is cost unfortunately😔
Thanks to @donatemask.bsky.social there is a way
December 29, 2025 at 6:10 PM
Whenever I see a surgical mask in use, I engage in conversation. Even if its a doctor at a hospital.
Many honestly are not educated in airborne pathogen prevention....yet.
A hindrance to switching from surgical to N95/respirator is cost unfortunately😔
Thanks to @donatemask.bsky.social there is a way
Many honestly are not educated in airborne pathogen prevention....yet.
A hindrance to switching from surgical to N95/respirator is cost unfortunately😔
Thanks to @donatemask.bsky.social there is a way
Anyway we had a relaxing off-grid family getaway this long weekend. Introduced kid #2 to the board games of checkers and Pictionary and got some great sledding in.
While smartphones do a great job of basic image processing that used to take a lot of time with digital photography, they are increasingly altering reality for an algorithmic preference. Example shown: Extracting too much detail from shadows and over-correcting white balance.
December 29, 2025 at 2:15 AM
Anyway we had a relaxing off-grid family getaway this long weekend. Introduced kid #2 to the board games of checkers and Pictionary and got some great sledding in.
While smartphones do a great job of basic image processing that used to take a lot of time with digital photography, they are increasingly altering reality for an algorithmic preference. Example shown: Extracting too much detail from shadows and over-correcting white balance.
December 29, 2025 at 1:59 AM
While smartphones do a great job of basic image processing that used to take a lot of time with digital photography, they are increasingly altering reality for an algorithmic preference. Example shown: Extracting too much detail from shadows and over-correcting white balance.
Reposted by David Elfstrom 🍁
Solstice Drive to St. Anthony
Christopher Pratt
2008
Christopher Pratt
2008
December 21, 2025 at 12:30 PM
Solstice Drive to St. Anthony
Christopher Pratt
2008
Christopher Pratt
2008
This EXACTLY why it's crucial to have the proposed revisions to CSA Standard Z94.4 (Selection, use, and care of respirators) accepted and adopted. It covers ALL industries.
Healthcare workers must NOT continue to be exempt from the same protections offered in other sectors!
Healthcare workers must NOT continue to be exempt from the same protections offered in other sectors!
"Half of you may die, but that's a sacrifice we're willing to make." - the BCCDC to healthcare workers ((:
December 19, 2025 at 1:39 AM
This EXACTLY why it's crucial to have the proposed revisions to CSA Standard Z94.4 (Selection, use, and care of respirators) accepted and adopted. It covers ALL industries.
Healthcare workers must NOT continue to be exempt from the same protections offered in other sectors!
Healthcare workers must NOT continue to be exempt from the same protections offered in other sectors!
Reposted by David Elfstrom 🍁
For comparison, this is Christopher Anderson's photography when he's NOT trolling for everything he's worth. Every choice made in the photos of this administration is a choice. It's fucking art, is what it is.
December 17, 2025 at 6:37 AM
For comparison, this is Christopher Anderson's photography when he's NOT trolling for everything he's worth. Every choice made in the photos of this administration is a choice. It's fucking art, is what it is.
Reposted by David Elfstrom 🍁
We have the technologies we need to cut pollution from the industrial sector. In our new report, we take a deep dive into an immediate, practical opportunity: electrifying low- and medium-temperature process heat in manufacturing food, beverage, paper and chemicals. www.bloomberg.com/news/article...
New Roadmap Shows How to Cut a Surprisingly Big Source of Emissions
Electricity can replace natural gas to provide the low- and medium-grade heat needed to make food, paper and chemicals.
www.bloomberg.com
December 16, 2025 at 6:51 PM
We have the technologies we need to cut pollution from the industrial sector. In our new report, we take a deep dive into an immediate, practical opportunity: electrifying low- and medium-temperature process heat in manufacturing food, beverage, paper and chemicals. www.bloomberg.com/news/article...
The open-source infinitely repairable air cleaner. An exceptional choice for indoor air quality. I can personally vouch for the Standard model. Extremely quiet, highly energy efficient performance with high clean air delivery rate.
It’s here!!! 🎉 The North Box Polaris Air Purifier Kit is now available in our charity store. 💻 🛍️
🛒 buymask.ca/products/north-box-polaris
Built for larger, high-traffic spaces, the Polaris comes in two models:
🔹 Standard – one-speed
🔹 Ultra – built-in PWM speed control
🧵 1/2
🛒 buymask.ca/products/north-box-polaris
Built for larger, high-traffic spaces, the Polaris comes in two models:
🔹 Standard – one-speed
🔹 Ultra – built-in PWM speed control
🧵 1/2
December 17, 2025 at 1:45 AM
The open-source infinitely repairable air cleaner. An exceptional choice for indoor air quality. I can personally vouch for the Standard model. Extremely quiet, highly energy efficient performance with high clean air delivery rate.
Reposted by David Elfstrom 🍁
If you work in a Canadian healthcare setting (or other workplace) where COVID-19 or other pathogens *might* be present, and want to determine what the proper standards-compliant PPE is for your workplace, the CSA provides an interactive tool that will identify that and generate a printable report.
Respirator Selection Tool
This tool is for the selection of respirators for protection from bioaerosols and is for use in conjunction with CSA Z94.4, Selection, use, and care of respirators.
www.csagroup.org
December 8, 2025 at 2:37 PM
If you work in a Canadian healthcare setting (or other workplace) where COVID-19 or other pathogens *might* be present, and want to determine what the proper standards-compliant PPE is for your workplace, the CSA provides an interactive tool that will identify that and generate a printable report.
When public health advises 40%-60% relative humidity to prevent viral transmission it runs smack up against the domain of building science and engineering. Water is the enemy of buildings. Condensation at 19°C & 43% RH, and -7°C outdoors.
That's why Health Canada recommends 30%-50%. /1
That's why Health Canada recommends 30%-50%. /1
December 5, 2025 at 3:35 PM
When public health advises 40%-60% relative humidity to prevent viral transmission it runs smack up against the domain of building science and engineering. Water is the enemy of buildings. Condensation at 19°C & 43% RH, and -7°C outdoors.
That's why Health Canada recommends 30%-50%. /1
That's why Health Canada recommends 30%-50%. /1
This is amazing! It makes complete sense (not going to spoil it, read the article)
1. Some good news at last. This week’s column is about the amazing thing a couple of us stumbled into three years ago, which we’ve now developed into a global research programme. It doesn’t change everything, of course, but it could help change quite a lot. + 🧵 www.theguardian.com/commentisfre...
Over a pint in Oxford, we may have stumbled upon the holy grail of agriculture | George Monbiot
I knew that a revolution in our understanding of soil could change the world. Then came a eureka moment – and the birth of the Earth Rover Program, says Guardian columnist George Monbiot
www.theguardian.com
December 5, 2025 at 12:04 PM
This is amazing! It makes complete sense (not going to spoil it, read the article)
Reposted by David Elfstrom 🍁
L.A. redesigned a road to slow traffic. People fought to reverse the safety improvements and won. Then one of the advocates hit and killed a woman walking her dog (the dog died too).
This should be a lawsuit. The city is liable along with the driver.
www.washingtonpost.com/business/int...
This should be a lawsuit. The city is liable along with the driver.
www.washingtonpost.com/business/int...
America’s plan to protect pedestrians failed. A young woman’s death reveals why.
U.S. officials adopted Europe's Vision Zero initiative, but many cities have seen an increase in pedestrian fatalities despite efforts to improve road safety.
www.washingtonpost.com
December 4, 2025 at 10:10 PM
L.A. redesigned a road to slow traffic. People fought to reverse the safety improvements and won. Then one of the advocates hit and killed a woman walking her dog (the dog died too).
This should be a lawsuit. The city is liable along with the driver.
www.washingtonpost.com/business/int...
This should be a lawsuit. The city is liable along with the driver.
www.washingtonpost.com/business/int...
Reposted by David Elfstrom 🍁
CAVI launched a new initiative today to expand our impact beyond public libraries. Please share!
CAVI is pleased to share that our Canadian Library CO2 monitor project is now complete. CAVI and other donors have contributed over 400 high quality CO2 monitors to libraries across Canada, reaching over 30% of the Canadian population. (1/5)
December 4, 2025 at 3:10 PM
CAVI launched a new initiative today to expand our impact beyond public libraries. Please share!
Reposted by David Elfstrom 🍁
Tetra Pak just launched a heat-pump-based pasteurization system that can cut energy use by up to 77%.
Electrification + heat recovery = massive efficiency gains. This is the kind of behind-the-scenes innovation that quietly transforms entire sectors.
www.foodtechbiz.com/business-upd...
Electrification + heat recovery = massive efficiency gains. This is the kind of behind-the-scenes innovation that quietly transforms entire sectors.
www.foodtechbiz.com/business-upd...
Tetra Pak launches integrated heat pump system to electrify pasteurization and cut energy use by up to 77%
Tetra Pak announces the expansion of its Factory Sustainable Solutions portfolio with its new Tetra Pak Integrated Heat Pump system for pasteurizers, designed t
www.foodtechbiz.com
December 2, 2025 at 7:30 AM
Tetra Pak just launched a heat-pump-based pasteurization system that can cut energy use by up to 77%.
Electrification + heat recovery = massive efficiency gains. This is the kind of behind-the-scenes innovation that quietly transforms entire sectors.
www.foodtechbiz.com/business-upd...
Electrification + heat recovery = massive efficiency gains. This is the kind of behind-the-scenes innovation that quietly transforms entire sectors.
www.foodtechbiz.com/business-upd...
As the story goes, when I was a wee lad at the end of a family dinner gathering I got frustrated, screaming "CLOCK FINGS!" over and over. My grandmother was the one to realize I meant the clock face on the After Eight's box. They let me pass the box around, as I had once done months before.
This box showed up in our kitchen area at work and it brought back memories.
Anyone else grow up thinking this was the height of rich people decadence?
All I remember is that if my parents sprung for a box of After Eight, it was a special dinner.
Anyone else grow up thinking this was the height of rich people decadence?
All I remember is that if my parents sprung for a box of After Eight, it was a special dinner.
December 1, 2025 at 2:30 AM
As the story goes, when I was a wee lad at the end of a family dinner gathering I got frustrated, screaming "CLOCK FINGS!" over and over. My grandmother was the one to realize I meant the clock face on the After Eight's box. They let me pass the box around, as I had once done months before.
Reposted by David Elfstrom 🍁
This phenomenon, where red states use far more electricity per capita than blue states, has been know for 40 y, as shown by Evan Mills and Art Rosenfeld in 1987:
escholarship.org/content/qt59...
It is due to the lack of efficiency standards and conservation programs in red versus blue states
escholarship.org/content/qt59...
It is due to the lack of efficiency standards and conservation programs in red versus blue states
December 1, 2025 at 2:12 AM
This phenomenon, where red states use far more electricity per capita than blue states, has been know for 40 y, as shown by Evan Mills and Art Rosenfeld in 1987:
escholarship.org/content/qt59...
It is due to the lack of efficiency standards and conservation programs in red versus blue states
escholarship.org/content/qt59...
It is due to the lack of efficiency standards and conservation programs in red versus blue states
Reposted by David Elfstrom 🍁
If LLM data centres that serve generative AI platforms were erased from the Earth…
…we’d be fine.
They prop up nothing of essential value we can’t do ourselves.
If we let them proliferate for a generation, we may lose institutional expertise.
…we’d be fine.
They prop up nothing of essential value we can’t do ourselves.
If we let them proliferate for a generation, we may lose institutional expertise.
November 30, 2025 at 5:16 PM
If LLM data centres that serve generative AI platforms were erased from the Earth…
…we’d be fine.
They prop up nothing of essential value we can’t do ourselves.
If we let them proliferate for a generation, we may lose institutional expertise.
…we’d be fine.
They prop up nothing of essential value we can’t do ourselves.
If we let them proliferate for a generation, we may lose institutional expertise.
Two dangerously close passes by a driver this morning on College Street in Toronto (warning: language). It looks like the driver decided to make an escape after the second one, rather than have me catch up at the next light.
November 26, 2025 at 2:01 AM
Two dangerously close passes by a driver this morning on College Street in Toronto (warning: language). It looks like the driver decided to make an escape after the second one, rather than have me catch up at the next light.
Forlorn gated entrance to the pedestrian bridge leading to Ontario Place from the exhibition grounds in Toronto. Signage in French and English describes the project ... /1
November 22, 2025 at 2:12 PM
Forlorn gated entrance to the pedestrian bridge leading to Ontario Place from the exhibition grounds in Toronto. Signage in French and English describes the project ... /1
HORSES
Art Deco entrance to the Horse Palace at Toronto's exhibition grounds, at twilight. Lit in yellow-blue complementary colours.
Art Deco entrance to the Horse Palace at Toronto's exhibition grounds, at twilight. Lit in yellow-blue complementary colours.
November 22, 2025 at 1:50 PM
HORSES
Art Deco entrance to the Horse Palace at Toronto's exhibition grounds, at twilight. Lit in yellow-blue complementary colours.
Art Deco entrance to the Horse Palace at Toronto's exhibition grounds, at twilight. Lit in yellow-blue complementary colours.
Reposted by David Elfstrom 🍁
We went from “you can’t trust anything on Wikipedia” to it being one of the only places on the web that’s likely to be correct and unbiased more often than wrong or driven by private interests.
November 21, 2025 at 5:09 PM
We went from “you can’t trust anything on Wikipedia” to it being one of the only places on the web that’s likely to be correct and unbiased more often than wrong or driven by private interests.
A pime example of #motonormativity. The expectation that automobiles are different and need accommodation that we don't accept for any other private property.
Removing a bike lane during winter so people can store their private proprety on public space
#polmtl #velomtl #outremont #bikemtl #mtlpoli
@davewalker.bsky.social's drawing still resonates⤵️
bsky.app/profile/dave...
#polmtl #velomtl #outremont #bikemtl #mtlpoli
@davewalker.bsky.social's drawing still resonates⤵️
bsky.app/profile/dave...
November 21, 2025 at 2:00 PM
A pime example of #motonormativity. The expectation that automobiles are different and need accommodation that we don't accept for any other private property.