Categories
Learn How to Sew

Which Face Mask Fabrics Do Hospitals Approve & Disapprove Of?

Which fabrics do Hospitals believe you should use for your homemade face mask? Find out.

Heads up: This post includes affiliate links like Amazon ones, so I earn from qualifying purchases (at no extra cost to you). Thanks for using them 🙂

This is part 2 of my how to make face masks series. In this post, you’ll learn what materials to make a homemade face mask out of. All advice is directly from hospitals.

This is useful for citizens who want to make their own fabric face mask, and those who want to donate to hospitals.

UPDATE: I have a new post about the most tightly woven cotton fabrics for masks.

Pin this image to bookmark the post for later 🙂

diy face mask fabric

I also have other articles in the ‘How to Make DIY Face Masks’ series:


What’s the best fabric for your DIY face mask?

2 or 3 layers of breathable cotton

The majority of hospitals recommend making cloth masks out of tightly woven cotton. For example, quilting cotton. A tighter weave is more impermeable according to John Muir Health Foundation.

For US buyers, Fabric.com has a massive range of cotton fabric. For UK/European buyers, Minerva Crafts has the biggest selection.

Froedtert Health says you can check whether your fabric has a tight weave by holding 2 layers of it and checking that you can’t see through it.

UPDATE: I have a new post on 4 of the most tightly woven cotton fabrics for masks.

The only exceptions to the “cotton rule” are a few hospitals that are using surgical sheets or are OK with breathable poly-cotton fabric.

Masks made from 100% synthetic fabrics aren’t a great choice. They generally won’t be breathable, although there are exceptions.

Using cotton flannel for the inner side of the mask is 50/50. Some hospitals are asking for it and others are telling people not to.

My understanding (which may be wrong) is that cotton flannel next to the face feels nice and soft, but flannel may hold too much moisture from your breath.

Using knit fabric also has mixed opinions. The majority of sources I checked requested woven fabric, but some (like Kaiser Permanente) said a cotton knit was OK too. The CDC also has a no-sew face-covering tutorial made from a cotton t-shirt.

A knit fabric could provide a better fit with fewer gaps. However, a risk with knit fabrics is that when they’re stretched, the holes between each thread open up further.

Here’s some close-ups of a white cotton t-shirt to demonstrate:

white cotton t-shirt fabric for homemade face mask
I held up a single layer of my light-weight, cotton t-shirt to sunlight. Can you see the holes between each thread? These will get bigger when stretched.
close up of white cotton t-shirt for homemade face mask
Here’s a zoomed in look at the same lightweight cotton t-shirt.

Hospitals recommend using 2 or 3 layers of fabric.

Make sure you can breathe through 2 or 3 layers of whatever fabric you use.

What fabric does the World Health Organization (WHO) recommend?

WHO recommends 3 layers:

  • A water repellent outer layer.
  • A polypropylene filter insert. This is a spun bond non-woven material. More info here.
  • A water-absorbent inner layer to capture your droplets.

Here’s their explanation in video format:

Preferred colours

If you’re donating your mask to a hospital, they seem to prefer plain colors, especially white.

Red fabrics are a risk because the color might run in the wash.

If you only have patterned fabric on hand, you might want to use gender-neutral prints. Cameron Memorial Community Hospital hinted that some medical professionals might be uncomfortable wearing fun novelty print masks. They said, “please remember that both men and women will be using these masks.”

**I Find the Best Free Sewing Patterns and Share Them Every Thursday. Don’t miss out. Join the Email List :)**

Pre-wash and dry your fabric

Make sure you pre-wash and dry your fabric on high heat. Ideally multiple times.

The industrial washing machines and dryers hospitals use may shrink your mask. Gritman Medical Center said “the very high heat wash that Gritman is putting these finished masks [through] is shrinking even pre-shrunk fabrics”.

Which fabrics to use (evidence):

“Use good quality, tightly woven cotton fabric (i.e. quilting fabric).”

Emerson Hospital. Source: Facebook post by the hospital. [accessed: 30 March 2020]

“Use either fabric:

– 100% cotton or cotton blend woven 6 to 8 oz (in densities similar to dress shirt or bed sheet fabrics)

– 100% cotton or cotton blend jersey knit 6 to 8 oz + All masks will use 2 layers of fabric per the pattern and instructions”

Kaiser Permanente. Source: https://about.kaiserpermanente.org/content/dam/internet/kp/comms/import/uploads/2020/03/02_COVID_Mask-Instructions_v9.pdf [published: 27 March 2020]

“Fabric for outer layer, recommend thread count 750 or higher as the tighter weave is more impermeable; inner layer should be 100% cotton.”

John Muir Health Foundation. Source: http://thewannabegrandma.com/wp-content/uploads/2020/03/JMHF_Face-Mask-Specs_COVID19_Flyer.pdf [accessed: 2 April 2020]

“Cotton fabric – Double Layer, 400 count Cotton or 140 count muslin.”

Cayuga Health System. Source: https://cayugahealthsystem.org/wp-content/uploads/2020/03/How-to-make-a-Face-Maskedited.pdf [accessed: 31 March 2020]

Preshrunk 100% cotton of a tight weave (white is preferred, but patterns and colors are acceptable.)

– 1 yard creates approximately 5 masks”

Bassett Healthcare Network. Source: https://www.bassett.org/covid-19/protective-fabric-masks [accessed: 31 March 2020]

“…washable, double-sided cloth masks…”

Slidell Memorial Hospital. Source: Facebook post by the hospital. [accessed: 30 March 2020]

– Please use cotton, such as cotton sheets.

– Create the mask using two layers of material and include a “pocket” on the inside where the mask touches the face so that we can insert a filter.

Cambridge Health Alliance. Source: https://www.challiance.org/about/newsroom/personal_protective_equipment_ppe_homemade_donatio_1180. [accessed: 30 March 2020]

– Recommended fabric for the outer portion of the mask includes heaver, non-stretch fabric such as denim, duck cloth, canvas, twill, or other tight woven fabric.

– Recommended fabric for the inner lining and filter pocket can be other cotton, cotton-blend non-stretch fabric. It can be thinner and softer, but again recommended minimal or non-stretch.

– Must be laundered in HOT water prior to sewing to prevent future shrinkage.

Polyester or other less breathable fabric will not work as well, due to moisture produced when breathing.

– If using denim or other fabric that is being “recycled”, please be sure it is clean and in good shape. Worn or dirty fabric will not be protective.

Owensboro Health Regional Hospital. Source: https://www.owensborohealth.org/news-events/news-media/2020/fabric-surgical-masks-information/. [accessed: 30 March 2020]

“A tightly woven cotton, such as a dress shirt, sheet, or similar material, for the front layer.

Softer cotton, such as flannel, for the back layer.”

Atlantic Health System. Source: https://www.atlantichealth.org/patients-visitors/donate-volunteer/donate-supplies-covid-19/make-facemask-help-covid-19.html [accessed: 31 March 2020]

“We request a tightly woven cotton fabric be used as the outer layer. Quilting cotton is excellent.

A softer cotton such as flannel can be used as the inner layer if desired, but quilting cotton is also an acceptable inner later.

Dartmouth-Hitchcock Health. Source: their Facebook page [published: 23 March 2020]

100% cotton fabric outer layer; or muslin, pillow ticking or cotton/poly blend if breathable
– White/ivory, unprinted material is best if available
– Clean cotton bedsheets can be used as long as they are clean, unstained and breathable

Cloth for interior liner
– Cotton diaper cloth, cotton sheets or same material as using for the outer layer

Bronson Health. Source: https://www.bronsonhealth.com/app/files/public/8410/OFFICIAL-Bronson-Face-Mask-Template.pdf [published: 20 March 2020]

“- Please use 100% cotton or 50/50 cotton/poly blend.
Wash and dry fabric before sewing so masks don’t shrink.”

Lowell General Hospital. Source: https://www.lowellgeneral.org/news-and-media/news/calling-our-crafty-community [published: 23 March 2020]

“Masks should be constructed from tightly woven, high thread count cotton fabrics.

The fabric should not have any stretch, and should not be knit (i.e. t-shirt material).

Recommended fabrics include: Poplin, Shirting, Sateen, and Percale in 100% cotton.

A possible source of fabric is high thread count sheets and pillow cases.

Wondering if your fabric will work? A simple way to check is to fold it into two layers. You shouldn’t be able to see through the fabric, but you should still be able to breathe if you hold it over your mouth.

Before you start, fabrics should be washed and dryed on Hot in order to pre-shrink them.”

Froedtert Health and the Medical College of Wisconsin. Source: their mask pattern instructions. [accessed: 30 March 2020]

Fabrics to avoid (evidence):

“Note that fabric that is breathable is not the same as fabric [you] can breath[e] through. There’s many so-called waterproof breathable fabrics – or MBF’s – that are used for outdoor gear because they repel water and are breathable but would make a poor choice for a face mask.”

Michigan Health Improvement Alliance. Source: https://www.covenanthealthcare.com/Uploads/Public/Documents/Workfiles/Volunteers/Face-Mask-Guide.pdf [accessed: 3 April 2020]

Water repellent fabric is NOT required.”

Cameron Memorial Community Hospital. Source: https://www.cameronmch.com/wp-content/uploads/2019/03/CMCH_COVID-19-DIY-Masks-Instructions-for-Web-03_26_2020-updated_Linked-2.pdf [published: 26 March 2020]

“- No red fabrics please – the color may run when laundered and disinfected.”

Bassett Healthcare Network. Source: https://www.bassett.org/covid-19/protective-fabric-masks [accessed: 31 March 2020]

“Please avoid synthetic materials as they do not breathe well.”

Dartmouth-Hitchcock Health. Source: their Facebook page [published: 23 March 2020]

PLEASE DO NOT USE FLANNEL OR LINE THE MASK WITH ANYTHING.”

Emerson Hospital. Source: Facebook post by the hospital. [accessed: 30 March 2020]

“Please remember that both men and women will be using these masks.” [There was no context about this, but my interpretation is that they don’t encourage making masks with fun novelty print fabrics.]

Cameron Memorial Community Hospital. Source: https://www.cameronmch.com/wp-content/uploads/2019/03/CMCH_COVID-19-DIY-Masks-Instructions-for-Web-03_26_2020-updated_Linked-2.pdf [published: 26 March 2020]

Pre-wash fabrics (evidence):

“Must be laundered in HOT water prior to sewing to prevent future shrinkage.”

Owensboro Health Regional Hospital. Source: https://www.owensborohealth.org/news-events/news-media/2020/fabric-surgical-masks-information/. [accessed: 30 March 2020]

“Please wash and dry your fabric 2 to 3 times before cutting. These masks will be laundered over and over again and we don’t want them to shrink.”

Kaiser Permanente. Source: https://about.kaiserpermanente.org/content/dam/internet/kp/comms/import/uploads/2020/03/02_COVID_Mask-Instructions_v9.pdf [published: 27 March 2020]


Free Sewing Patterns Every Thursday

Free patterns. Your inbox. Beautiful.