Brooke BinkowskiPSA from a southern Californian: Your N95s and KN95s (and even your cloth masks to a certain extent) will help a lot against wildfire smoke. Stay safe out there, friends.
I just realized I have some expertise here that might help if you have questions you need answered. I was a breaking news reporter for a billion years and around here that means covering a lot of wildfires up close and personal (without proper gear, but I digress.) As a highly curious environmental and indigenous rights reporter I learned a lot of fire science as well. If you have questions about how to deal with an ugly fire season I can try to answer them as best as I can.
Also those Corsi-Rosenthal boxes are supposed to be excellent but I haven't tried them out. I do use air filters when things get exceptionally bad, and humidifiers can help too, at least around here where humidity can get so low that it sucks all the moisture out of your eyes and nose
Jesse@brooklynmarie I have an air filter in my apartment that I got allergies and then proved useful for Covid isolation — wondering if it’s worth getting a second one or just the one is enough. Probably wouldn’t buy one but would consider making a C-R box…
BeckyBSF@misc @brooklynmarie Can’t hurt. If your air conditioner has filter change that too.
Frances LarinaHEPA filters supposedly work best at around 70-77% humidity, on a gentle curve, so adding air moisture should help during fire/smoke season. We tried it during the CA West Coast fires in 2017-2021 and it certainly *seemed* to help? It definitely felt much better.
Texan_Reverend@brooklynmarie As someone in Washington, I can personally attest to the value of a Corsi-Rosenthal Box. The 4-filter version with a box fan on top will clean more air per minute than any consumer HEPA air purifier from Amazon or WalMart.
The best filters are Filtrete 1900 from Amazon, Target, WalMart, Lowes, etc. 20" wide is needed to form a box that fits a box fan on top, but any height works; 30" will give you the longest lasting filters.
Here are video & photo guides:
https://www.youtube.com/watch?v=aw7fUMhNov8
The best filters are Filtrete 1900 from Amazon, Target, WalMart, Lowes, etc. 20" wide is needed to form a box that fits a box fan on top, but any height works; 30" will give you the longest lasting filters.
Here are video & photo guides:
https://www.youtube.com/watch?v=aw7fUMhNov8
@brooklynmarie Any regular 20" box fan will work, and if the Filtretes aren't available, the MERV-13 rating is the important metric to look for on alternatives
@Texan_Reverend THANK YOU!
@brooklynmarie I also have a pinned thread about respirators which could be helpful for folks dealing with wildfire smoke:
https://kind.social/@Texan_Reverend/109275654593005478
The respirator/mask has to seal really tightly to your face, or so much of the smokey air will just leak around it and irritate your throat, lungs, and eyes anyway.
https://kind.social/@Texan_Reverend/109275654593005478
The respirator/mask has to seal really tightly to your face, or so much of the smokey air will just leak around it and irritate your throat, lungs, and eyes anyway.
Texan_Reverend (@[email protected])
For effective masking, the keys are fit/seal, long-term comfort, & high filtration respirators with headbands. A disposable N95 can be used for about 12-24 hrs unless damaged, soiled, or not sealing. Exercise loops can cover beards for a proper seal that facial hair prevents. Great N95 options, filtering 99%+, for various face shapes: (Amazon prices) Dräger 1950 :xplore1900: ~$2.25 Stable seal 3M 9205/9210 :aura: ~$1.50 HCW model 3M 9105 :vflex: ~$0.75 Easiest breathing #CovidIsAirborne Thread:
sam@Texan_Reverend @brooklynmarie if you're trying to mitigate wildfire smoke rather than covid MERV12 will probably work OK if you can't find MERV13
Jennifed
AJ Fidalgo (voice actor)I built a #CorsiRosenthalBox last year and it's been great for situations where we need better-than-normal air circulation in the house. Like today, when the smoke from Canada is making the air pollution levels intolerable.
My CR Box has five filters, I put one on the bottom too.
@MrF @brooklynmarie That's excellent! I really like the cardboard reinforcement on the sides. If you were to add a tape or cardboard shroud on top with a ~15" opening, you could boost it's efficacy another 15-40%. It's wild how much it helps. It even mitigates a little bit of the sound.
@Texan_Reverend @brooklynmarie when I was building it I was confused as to the function of the shroud and opted to skip it. Your explanation actually gives me a reason to add one.
@MrF @brooklynmarie The corners and outside edges where the fan blades don't reach all the way to the housing just wind up being negative pressure zones that pull air into the box without being filtered. That also generates air turbulence which elevates the noise level. The shroud blocks those areas to keep the fan only pushing air up and out. That's how it helps the whole assembly be more efficient/effective and a bit less noisy.
@MrF @brooklynmarie PS: if it's a Utilitech box fan, it benefits from going all the way down to a 14" diameter shroud opening. That said, all box fans tested were better with a 15" shroud opening than with no shroud at all. The Utilitech just benefits even more from going slightly smaller.
Jonah Stein@Texan_Reverend @brooklynmarie Even better when you use MERV 16-17, which are effective against smoke.
@jonahstein @brooklynmarie The testing shows MERV 13 to be great for smoke, too! MERV 16+, while great, is not available in most stores, often runs way more expensive, and reduces airflow considerably. MERV 13 is the most readily accessible level that's still effective for aerosols, allergens, and smoke. That's how they landed on it as the recommendation. Higher is great where it can be done, but 13 is effective, allows the fan the move lots of air, and isn't exotic in price or availability.
ProtectiveHen@Texan_Reverend @brooklynmarie And remember that a cheap #CorsiRosenthalBox placed in a room for meetings will help people to avoid walking away with #Covid! #AirFiltrationWorks
Kevin Leecaster@Texan_Reverend @brooklynmarie
Great instruction sheet. Richard Corsi was a huge help in our efforts toward getting WHO to finally acknowledge that covid is airborne too. https://engineering.ucdavis.edu/news/science-action-how-build-corsi-rosenthal-box
Great instruction sheet. Richard Corsi was a huge help in our efforts toward getting WHO to finally acknowledge that covid is airborne too. https://engineering.ucdavis.edu/news/science-action-how-build-corsi-rosenthal-box
Science in Action: How to Build a Corsi-Rosenthal Box
Learn how to build a Corsi-Rosenthal box. The device was created to provide significant reduction in the amount of virus-laden, aerosol particles that are in the air. Follow along as Dean Richard L. Corsi, co-inventor, shows you the major components of this device, and how to build one.
Xenofact (he/him)
@Texan_Reverend @brooklynmarie can agree. They also do a treat on pollen.
Daniel Martin@Texan_Reverend @brooklynmarie
Given how relatively cheap box fans are compared to filters, wouldn't it be cheaper and easier to just buy two fans and slap a single filter onto the back of each? That should move more air than the single box.
@fizbin @brooklynmarie That's definitely one school of thought. A single filter directly mounted like that restricts the fan's air movement to about half, and stresses the motor more. It's also harder to get that arrangement pointed upward for better air mixing. Plus, two fans means even more noise.
It's absolutely an option, and if you already have fans on hand, just adding a single filter to multiple fans could very much be the most economical plan.
It's absolutely an option, and if you already have fans on hand, just adding a single filter to multiple fans could very much be the most economical plan.
@fizbin @brooklynmarie If starting from scratch, a full Corsi-Rosenthal Box is quieter than two box fans with single filters and moves about the same volume of cleaned air. Not having much restriction means the fan's motor is less likely to wear out prematurely. For costs, the filters generally last 6-12 months. With 2 fans running single filters, each filter will be working harder and likely need replacement in half that time. So, in that same 6-12 months, you'd still be buying 4 filters.
@fizbin @brooklynmarie That makes sense if you're expecting to run the filter setup consistently for mitigating allergens, aerosols, and smoke. However, if you just need something to get through infrequent wildfire smoke events, the single filter per fan setup could be less expensive up front, easier to store, and still useful as regular fans when you need them. So, a lot comes down to anticipated usage, really
Katanova the Sunpunk@Texan_Reverend
Seconding this. I build a 5-filter cube.
Actually I have one next to me right now. Here it is.
The legs on the back side are toilet paper tubes cut in half and taped.
I use 3x 20x20x2 and 2x 16x20x2 MERV 13 filters
@brooklynmarie @jessmahler
@Texan_Reverend
The use of the 5-filter cube very slightly improves overall airflow over 4-filter versipn, while extending the life of all the filters of the apparatus. Same amount of dust through more filters means less dust going into each filter, thus they last longer.
Using 2 inch filters also provides more filter surface area, again improving longevity.
@brooklynmarie @jessmahler
@Anarkat @brooklynmarie @jessmahler Right on! That's a creative setup with the feet at the back.
I'll add one thing on filter depth: the micropleat structure in Filtrete's 1" filters yields comparable surface area and airflow to standard 2" MERV-13 filters. Along with the wire mesh to protect those pleats from minor bumps and dents, it's a big part of why I prefer and recommend the Filtrete models.
I'll add one thing on filter depth: the micropleat structure in Filtrete's 1" filters yields comparable surface area and airflow to standard 2" MERV-13 filters. Along with the wire mesh to protect those pleats from minor bumps and dents, it's a big part of why I prefer and recommend the Filtrete models.
Lily Star