Updated 3/27/2020 3:15 PM
Thank you for helping with the COVID-19 homemade mask effort! We are so grateful for your willingness to step up and contribute in the event that our healthcare workers on the frontlines run out of their vital protective gear.
Here is a set of instructions, material list, and a pattern you can print on two pieces of standard printer paper and tape together with the light blue crease line as the point where the two pieces of paper should meet. (It's a pretty simple pattern and you may not even need it but it may be helpful for beginners.)
There are a ton of videos on Youtube with a variety of homemade mask solutions. We have watched a LOT of them. Our conclusion is based on the video below, titled "HOW TO MAKE FACE MASK WITH FILTER POCKET AND ADJUSTABLE WIRE | SEWING TUTORIAL".
Update: The only change we are suggesting is that rather than ear loops, that the elastic goes around the back of the head.
This takes 1 yd. of elastic. Any width of elastic works with this design.
If you do ear loops instead, please cut each piece to 12" long.
This video doesn't address filter materials but we are suggesting replaceable filters made out of a MERV 13 air filter which are made to capture viral particles.
Thank you for your help, stay safe and healthy!
Please send your questions to firstname.lastname@example.org.
Note: We've found the Aprilaire filters to be easiest to work with. Some of the other types we've tried are difficult to disassemble without tearing the filter fabric.
Pre-wash cotton fabric
Cut a 7.5" x 15" rectangle of fabric
Serge or zigzag stitch along short sides
Fold in half with right sides together, iron crease
Measure 1.5" in from edges and sew, leaving a 4.5" opening
Iron open the seams
Turn right-side out and top stitch both sides, creating a finished opening
Measure 0.5" down from opening, fold there and iron flat
Clip or pin in place
Sew around all edges very close to edges
Fold with three pleats, clip or pin in place
Sew edges holding pleats in place
Pin fabric or bias tape to front side of one pleated edge and wrap around to back side
Sew bias tape or fabric in place being sure to tack it down on back side for nicely finished edges
Repeat on other side
Wrap bias tape or fabric around pleated edges and pin in place.
Sew down backside, creating a channel for elastic
Place twist tie into tiny pocket at top edge
Clip or pin in place, sew closed with twist tie inside
Using a safety pin attached to the elastic, feed through channel entering at the bottom of the right-hand side (coming out the top right), enter the top of the left side (coming out the bottom of the left) so ends can be tied at the nape of the neck to fit. This uses approximately 36” of elastic. 1/4” is ideal but any size will work.
See note below regarding optional filters. Do not put them in when you submit the masks - the masks may be laundered before use and we don't know how the filter material might be affected by laundering. Cut these to size so they fit inside the mask pocket - approximately 6” x 2.5”.
Apparently, MERV 13 (or higher) air filters are effective at trapping viral particles. We only need the filter paper, so you can take these apart, gently removing the wire mesh from the material and cut rectangles to fit inside the pocket of the mask. (See the note above in the material list about which filters are easiest to work with!)
Ideally, these will be replaceable filters so cut more than the number of masks you make and provide to go with the masks. If you are able to get MERV 13 filters, note this when you submit these with your masks so hospital workers know what they are. This should really up the efficacy of the masks.
Taking the filters apart is not an elegant process. Parts of the filter material may degrade as you take it apart. This is normal. Just cut as many filters as you can once you free the filter fabric from the cardboard and aluminum mesh. For example, in a perfect world, a 14” x 20” x 1” filter would make 36 mask filters but we ended up with 34 as two of them were damaged from the deconstruction process.
Click the image below to get a full-sized version in a new browser tab, then ask your browser to print the page.
Sew Creative has machines starting at $179.
Aspenleiter may expedite repairs for mask making.
Here are the options for delivering masks:
We've revamped the mask making step-by-step and added some images!
Here's a video showing how to break down an Aprilaire 413 filter.
Listen to Dr. Nick discuss the homemade mask effort on 98.9 The Buzz this morning.
Lisa at Sew Creative has received requests for 3,000 masks.
Thank you to the many of you working tirelessly to help us ensure that we will have a back up plan in case we run out of disposable personal protective equipment. A couple of things have come up that are worth communicating.
First, regarding safety of these masks with HVAC material. The HVAC filters that we are placing do not contain any fiberglass. They are obviously not OSHA approved and cannot be true replacements for disposable N95 masks. After review with several physicians with various training backgrounds, we feel they are a safe alternative as a last resort when all other options have been exhausted. We feel strongly that they are a better alternative than a bandanna, or nothing at all (very scary).
Secondly, there is a lot of confusion about who is accepting masks. We are accepting masks. We are a physician/community based impromptu organization. Some of us are affiliated with a single institution, however we are working for the good of all healthcare workers and will help direct resources wherever they are needed. If the masks we collect are not needed in our institution we will happily donate them other facilities in need. Some institutions in the Rochester area are issuing statements that they are not accepting cloth masks. Currently there is an urgent need for masks at another institution and we will begin shuttling masks in that direction.
Third, elastic is a hot commodity and the plans included in the video use a lot of it. Please consider altering the design if you have no elastic. Alterations that might work would be 12 inch loops loosely tied on each side of the mask so that they can be adjusted to hang around the ears, or a 20 inch tie on each corner so that they can be tied behind the head. Please feel free to be creative, so long as the mask can be secured to the healthcare provider in a way that protects them from viral transmission.
Thank you all for your contributions. You are helping.
Regarding use and re-use of home made masks. We recommend machine wash on high heat after each shift if these masks are to be removed. The filter needs to be removed prior to machine wash. The filter can be treated the same as N95 masks for re-use (see the below instructions for N95 re-use)
The below was taken from a message board from American College of Emergency Physicians. It was posted by Dr. Salim Rezaie who obtained the information from Dr. Jennifer Lopez, MD (Austin, TX) and Dr. Peter Tsai, MD (inventor of N95 material).
When reusing N95 masks, leave a used respirator in dry, atmosphere air for 3-4 days to dry it out. Polypropylene in N95 masks is hydrophobic and contains zero moisture. COVID-19 needs a host to survive -- it can survive on a metal surface for up to 48 hours, on plastic for 72 hours, and on cardboard for 24 hours. When the respirator is dry in 3-4 days, the virus will not have survived.
You can also sterilize the N95 mask by hanging it in the oven (without contacting metal) at 70C (158F) for 30 minutes-it is reported that COVID-19 cannot survive at 65C (149F) for 30 minutes.
Use a wood clip to hang the respirator in the kitchen oven to do the sterilization.
When sterilizing N95 masks, be wary of using UV light--keep N95 masks away from UV light / sunlight. N95 masks are degraded by UV light because it damages the electrostatic charges in the polypropylene material. It is unclear how long the masks can be exposed to UV light before they are ineffective.
It is not a good idea to use cotton masks when taking care of infected patients. The effectiveness of a material made of cotton is not high-its fiber is not fine enough, and it cannot be charged. An N95 mask is so thin because it uses Polypropylene which is made of millions of microfibers layered on top of each other that have been permanently electrostatically charged. An electrical field ionizes the air and forces the ions deep into the microfibers which allows the polypropylene to act as a filter.
However, using a HEPA filter with a face mask might increase its effectiveness, but it may make it harder to breathe. If you place another media over a face mask, the resistance to breathing increases-it is the sum of the two together. When adding an extra layer, make sure it perfectly covers the whole mask. Keep in mind it may make it more difficult to breathe.