As the pandemic continues to consume key portions of our daily ritual, the process of leaving the house now includes locating keys, wallet, mask, and hand sanitizer. In many areas of the country, masks are now required in public places or even outdoors where six-foot distancing cannot be maintained.
The policy revolves around scientific evidence that masks help reduce the spread of germs, and therefore the coronavirus which causes Covid-19 and is credited with taking the lives of over 800,000 worldwide. While banter continues about the politics of wearing masks, another focus is on which types of masks are the most effective. Here’s a summary.
N95 Respirators and Surgical Masks
N95 masks are professional grade protection typical for first responders and medical personnel. Although the general public can acquire these masks, the shortage this year has put a priority on making sure health care workers are supplied first. These masks are highly efficient in preventing germ spread, however, it is critical that each mask is professionally fitted to the individual to achieve this level of safety. So, even if you can get an N95 mask, it’s likely similarly effective to most other masks without a professional fit test.
Surgical masks are very effective against viral spread and are recommended throughout the medical community. The general population can also find and wear this disposable option, however it may exceed the level of protection required outside the medical environment.
Homemade Cotton Masks
The general consensus across the medical community is that if everyone wears a face covering of some sort, it significantly reduces the spread of the virus. Even homemade masks fit the bill. The Center for Disease Control (CDC) recommends In addition to selecting the right materials to construct your mask with, CDC guidelines also recommend masks fit snugly but comfortably against the side of the face, and stay secured with ties or ear loops, include multiple layers of fabric, allow for breathing without restriction, and be able to be laundered and machine dried without damage or change to shape, so making sure your homemade mask fits properly is at least as important as what material you use to construct it.
In at least one study, the most effective cotton masks were constructed from two layers of high-quality, heavyweight “quilter’s cotton”. Equally effective options are two-layer masks made with thick batik fabric or a double-layer mask with an inner layer of flannel and outer layer of cotton.
Material can come from anywhere as long as it is cotton and breathable. Look at your t-shirts, flannel pajamas, and even pillowcases. Cotton face masks should be two to four layers thick, and provide a good fit.
According to John Hopkins Medicine, “Surgical or procedural masks provide protection against respiratory droplet spread. While cloth masks are not medical-grade, they may be helpful in non-patient settings to contain coughs and to remind people to not touch their face, but they are not suitable for providing medical care to patients.
Hepa Filter Vacuum Bags or Furnace Filters
In addition to cotton, you can make or purchase masks with HEPA filters. Researchers have verified the filters are one of the most effective options available. Yang Wang, an assistant professor of environmental engineering at Missouri University of Science and Technology conducted several studies in a controlled environment and found that allergy-reduction HVAC filters worked the best, capturing 89 percent of particles with one layer and 94 percent with two layers. A similar furnace filter captured 75 percent of particles with two layers, but required six layers to achieve 95 percent. The downside of the filters is a lack of breathability when used as the only material, alongside the risk of breathing in small particulates from the filter. To solve this problem, Wang suggests sandwiching the filter in between two pieces of high-quality cotton, and many masks currently have a built-in slot with that in mind.
If you have a 3-D printer, one option might be to print a mask. Companies online have provided printing files for free. You can line the printed mask with a coffee filter, HEPA vacuum bag, or cotton fabric.
If you aren’t sure of the quality of your materials, try the light test. Shine a light directly through the material. The less light that filters through the better because it means the material is dense enough to hold back viruses and other particulates. Again, just be sure breathing isn’t restricted by the density of the fabric.
In tests, coffee filters offered some protection, but even with several layers, didn’t offer a reliable level of safety. Plus, they are not washable. However, they are readily available and better than nothing so making a mask out of several layers is an option in the absence of preferred materials.
Making your own mask is fairly quick and easy, especially if you are proficient with a sewing machine. Do follow CDC guidelines to ensure a good fit, but remember that masks do more to protect others if you are carrying a virus than they do to protect you from contracting something. With this in mind, it’s still best to stay at home or practice physical distancing if you must go into public. Also, be sure to put your mask through the washing machine after each outing, placing it directly into the washing machine when you arrive home. Once the pandemic hits the rear view mirror, your supply of masks will work when staining wood, sanding planks, or even cutting onions in the kitchen.