How to Make a washable Mask w/ removable Filter Researched by: Steve Smith, Serenity Smith Forchion, Felicity Billings (anesthesiologist). If you have questions or suggestions, or wish to be added to a communication document to learn who has items to share, or ideas for distribution, Sign Up here https://forms.gle/iSDZqSX8YyWd7nzP9
THE FILTER The element that distinguishes the BTN style mask from many other homemade masks is the incorporation of a layer of Merv-13 filter material. MERV-13 is a grade that can filter down to .3 microns, small enough to stop a virus. How well it works will depend on many factors, including care taken to insert the filter material and care in fitting the mask to your face.
GETTING THE RIGHT FILTER In order to be ‘better than nothing’ for keeping COVID-19 virus out, it must meet these standards
need MERV-13 or higher: Merv "minimum efficiency rating value" measures the tightness of the weave and its ability to catch tiny particles down to .3 micron (including the COVID-19 virus).
Or: Home Depot has its own rating number system, FPR, "filter performance rating": need FPR number 10 or higher.
Or: 3M brand also has their own rating MPR. " micro particle performance rating": need minimum of 1900.
Some options we found. We focused on furnace filters. We found some already made that we are using, but also found a large wholesale distributor that would be the best to go to. TOP OPTION: Comes in a bolt of easy to use filter material!
Buy the filter material in rolls, instead of pulling it out of existing furnace filters.
CONTACT: Paul Lipinski / email@example.com / 1-800-667-8563 ext 182; Synthetic MERV 14/15 filter media / 24.6" wide x 100 ft long / ASH9MRS-246100 $117.50 for a roll plus shipping. They will cut down industrial rolls and rewind them for mask makers. Their fabric is Merv-14/15, Order and have it shipped UPS to you.
OTHER OPTIONS WE FOUND: You have to disassemble the furnace filter.
Brown and Roberts Hardware (local to us in Brattleboro, VT) has Ace brand Merv-13 furnace filters. Call Ed there at 802 257-4566
Flanders Brand Furnace Filter, go online to get some shipped: search this: PREpleat® M13 EXTENDED SURFACE PLEATED PANEL FILTERS
Productive Google search examples for rolls of the material: "MERV-13 filter fabric rolls," " hepa filter fabric rolls wholesale";
If you have a construction mask with replaceable filters you can cut replacements from the material to use. I have one that has a single replaceable filter (looks like a regular cupped filter) and one that has two replaceable filter (looks a bit like smoke mask). You should be able to get the single filter type at hardware stores, like Home Depot, Lowes, Ace Hardware etc, when you get the filter material.
We might want to start a new thread on making masks.
From a US Navy Chief Hospitalman (HMC, AKA "corpsman!")
I recently received an email from a Navy Reserve corpsman Chief Petty Officer (AKA "Hospitalman", HMC) with whom I served before retiring nearly a decade ago:
quote:BLUF: Medical supplies are for medical professionals but the general public should probably be encourage to wear cloth facial barriers while out in public. (Hopefully the general public is smart enough to stay home though.)
The experts (CDC, OSG, WHO, etc.) currently recommend that facemasks should be worn by sick people but healthy people do not need to wear facemasks. Having a mask cover a sick person's mouth and nose limits the spread of infectious material when the person talks, sneezes, coughs, or simply breaths. The mask does not protect the wearer; the mask helps to protect everyone around the wearer by restricting the pathogen from floating freely across the room.
When it comes to assessing the general public, wearing a mask does not protect the wearer from the virus. In fact, wearing/using medical PPE improperly may increase the chance of infection and unwittingly spread infectious material further. Wearing medical PPE against contagious agents is akin to wearing MOPP gear against a suspected biological attack. It does not matter what fancy gear a person might put on if the individual lacks the appropriate level of training, discipline, and execution during all stages of wear (i.e. don, decon, doff, disposal) because the person will still become contaminated. Wearing medical PPE by an untrained, undisciplined healthy person will not protect the person from getting sick. Having the general public wastefully burn through critical medical supplies that are desperately needed by healthcare professionals will exacerbate the pandemic crisis and lead to more needless deaths. That is the basic logic of the experts and I agree with them entirely when viewed from that angle.
However, let's turn the equation upside down.
Due to the 14-day incubation period, it is possible that people may be contagious and spreading the virus before the person feels sick or shows any symptoms of illness. It is not really possible to tell who is still healthy versus who is actually sick during that 14-day incubation period. Therefore, the "safest" assumption is to operate as if everyone is contagious/sick and apply standard precautions universally. When we operate under the assumption that everyone is contagious then the scenario changes and wearing a facial barrier makes far more sense.
Wearing a facemask does not protect the wearer from the virus, but wearing any sort of facial barrier over the mouth and nose will limit the spread of potentially infectious material to others. The barrier does not protect the wearer, the barrier helps to protect everyone around the wearer. As people cough, sneeze, talk, and breath the barrier serves to help contain the potential infectious material coming out of the person's mouth/nose and limit the distance that material might travel through the air, thus reducing the amount of potentially infectious material floating around that might get people sick.
If everyone is wearing a facial barrier in public then the barriers should help to protect everyone from each other.
The general public must not wear medical masks, especially N95 respirators, while supplies are at such critical levels. Medical masks and N95 respirators must be reserved for our healthcare professionals and first-responders. However, in addition to frequent hand-washing and following social distancing guidelines, the general public should probably be encouraged to wear cloth barriers over their mouth and nose while out in public.
The facial barrier does not need to be anything fancy. It just needs to comfortably fit over the wearer's mouth and nose and not interfere with breathing. There are numerous non-medical commercial products and lots of simple DIY designs out there. People can also potentially wear a neck gaiter, buff, balaclava, ski mask, motorcycle mask, UPF face shield, fishing mask, sun mask, sun gaiter, face tube, bandana, scarf, flash hood, shemagh, keffiyeh, niqab, (non-NIOSH) dust mask, or just about any cloth or paper barrier that covers over their mouth and nose that will catch a cough. (However you may want to continue to avoid the diaper mask, panty mask, and feminine napkin mask. Google it.) (Elevation masks/training masks might also be avoided since they restrict the ability to breath.)
Any simple facial barrier that helps keep droplets from floating across the room is all you're aiming for. You're not trying to filter out the virus during inhalation to protect yourself. You're trying to cut down on the airborne particles floating around as you exhale to protect others. That is the potential benefit from everyone wearing masks so there is no need to waste money buying specialty mask products from some profiteer selling snake oil. Plus the general public should not use medical masks and N95 respirators while medical supplies are still critically depleted.
Continue to conserve the medical supplies for the medical professionals. When properly worn by a healthcare professional a medical mask or N95 respirator may help keep them healthy. When medical masks are worn by the general public, they're just denying medical professionals desperately needed protection. Each medical professional that gets taken out of the fight, even for a short period, is one less person available to treat you or your loved ones.
Mythbusters Contamination, Spreading Germs (5:46), MythBusters, 2011 Mythbusters Contamination This MythBusters' segment exaggerates the level of contamination because Adam Savage is deliberately trying to spread the dye. However, it is still a good illustration of how easily and quickly invisible corona cooties can be spread and transfer to other people. Again, the "safest" assumption is to operate as if everything is potentially contaminated and take reasonable precautions to protect yourself. Frequent proper hand-washing is essential to fighting this pandemic. Don't touch anything in a store that you don't need to touch. Sanitize your hands before getting in your car after you leave a store or work. Immediately wash your hands upon arriving home (first thing). Wash your hands before eating. Sanitize high-touch surfaces regularly (i.e. smartphone, door knob, keyboard & mouse, office phone, steering wheel, gear shift, etc.). Wash you hands after using disinfectants and other chemicals. Take reasonable precautions but do not go crazy. A multi-stage CBRN DECON process for every product or package is not required. Failing to use disinfectants/chemicals properly can harm you. Covering food items with disinfectants/chemicals is not healthy and will likely cause problems. Be prudent but don't be paranoid.
Be smart. Be safe. Wash your hands and avoid the stupidity.
... Therefore, the "safest" assumption is to operate as if everyone is contagious/sick and apply standard precautions universally. When we operate under the assumption that everyone is contagious then the scenario changes and wearing a facial barrier makes far more sense.
The logic of self isolation and social distance is simple:
If one in 100 people are infected, the chance of you getting the virus from someone you meet is 1/100. If you meet another it has doubled, another and it has tripled ... every person you meet increases the chances that you will get infected.
Social distancing increases the path the virus must travel to infect you. If the virus spreads from a person as they exhale it will be an expanding cloud of the exhalation with a finite number particles of virus, the density of particles therefore drops with the distance from the center of this cloud as it expands, ie -- the chances of you getting in contact with a virus lessens substantially the further you are from said person.
Stay safe, minimize contacts with others, wear a mask outside the house, and keep a respectable distance from others.