Until recently, it was very uncommon to wear a face mask in the USA. But in recent years, massive wildfires have become more common in California and the Pacific North West. And now, with a worldwide pandemic, masks are becoming even more commonplace. Today, there is still a lot of confusion around face masks and respirators, how they differ, and how they function differently. The good news is that widespread adoption is driving innovation in this area.
The last thing you want is to wear a protective mask in a way that puts your health at risk. Keep in mind that a lot of this information may change over time as mask products and the laws that govern them improve. The data included here references analysis by other groups with no association to Woobi Mask or Airmotion Labs.
Face masks 101
The primary function of face masks is to prevent respiratory droplets from the wearer from spreading to others. Surgical masks are the primary type of face mask in that regard. They have three layers of non-woven or melt-blown fibers, with the middle layer being the primary filter. Surgical masks are single-use / disposable products that are inexpensive. Interestingly, the WHO (world health organization) recommends using surgical masks for at-risk groups. In contrast, the CDC (United States Center for Disease Control) does NOT recommend using surgical masks by any group, although these recommendations change periodically.
Three main criteria will determine if a mask works well to protect the wearer from inhaling airborne contaminants. Those are filtration performance, breathability (low resistance), and fit. Fit is the mask's ability to seal around the nose and mouth so that all air goes through the filter material and not around it. Surgical masks score high in terms of filter performance and breathability but score low in terms of fit. For all of the metrics above, there are qualitative data to report.
Cloth masks have not been typical since the last pandemic. The WHO and CDC recommend using cloth face coverings with four layers and cover your nose and mouth. Filtration and breathability vary greatly depending on the type of material. For instance: standard fabrics in bandanas and neck gaiters perform very poorly in regards to both. Simultaneously, purpose-built cloth masks (sampled from Amazon) have filter performance that varies widely (7 - 40%). Unfortunately, there are no standards or testing for these products. Breathability for cloth masks is very bad. Typically, many fabric layers need to be combined to obtain good filtration scores, at which point breathability is very poor.
The candle test
Because cloth masks' quality does not rely on scientific testing, a common test to determine if the mask is blocking enough air from the wearer is the candle test. Put on the mask, and try to blow out a candle from a few inches away. If you can't blow it out, then the mask is doing a good job.
What about cloth masks that advertise 99% filtration? Typically, that advertisement is misleading. Unless the entire mask is certified, it is unlikely that you will obtain that level of performance by wearing it. The mask company will often test a piece of filter material sealed to a test machine without testing the mask as a whole. Unfortunately, there are no rules which prevent companies from advertising this way.
Mask sanitation
With surgical masks, sanitization is pretty straightforward. With no recommended sanitation protocols, you should discard surgical masks after each use. For cloth masks, as they could potentially be catching a pathogen, the WHO recommends washing them each day in hot water at least 140 degrees Fahrenheit. Important to note here that a typical washing machine's "Hot" cycle is approximately 130 degrees Fahrenheit. If your washer has a "Sanitize" setting, that is more than sufficient at around 165 degrees. The general public commonly overlooks this step. It is critical when considering you are placing the item back on your face.
Respirators
A respirator's primary function is filtering the air that the wearer will breathe. The purpose of a surgical mask and a respirator is the opposite. Thus, it is quite common to see masks and respirators layered in medical settings to achieve both functions. The US testing agency NIOSH (U.S. National Institute of Occupational Safety and Health) tests and certifies respirators for use in the work environment. Standard certification ratings are N95, N99, and P100. The letter referencing the type of elements that will be filtered, and the number represents the filtration performance. 95%, 99%, and 99.97% respectively. With the most common level being the N95. Similar standards in other regions include KN95 and FFP2, which filter 95% and 94%.
What about breathability?
NIOSH also has testing standards for breathing resistance. All masks must perform below a pressure threshold that is widely understood to be uncomfortable. As a rule of thumb, masks with higher filtration levels typically also have slightly higher breathing resistance. However, this is not always consistent. But, it is one of the main reasons why N95 is much more common than a P100. Most users would find using most P100 masks as uncomfortable. It's essential to keep in mind that breathability is a rating typically taken when the mask filters well and has a good seal on the face. Most cloth masks appear to be breathable because they let a significant amount of airflow around the mask's sides. To those unfamiliar with a respirator, they will perceive more resistance the first time they wear one.
It's important to note that the term respirator does not mean the mask has a valve or does not have a valve. Also, it has no bearing on whether the mask is reusable or disposable.
The media often states that exhaust valves make masks more comfortable. But, that statement lacks detail. Respirators will indeed build up heat and humidity, and adding a vent will increase comfort. But an essential aspect of reusable respirator design is the use of one-way valves. This design reduces the effort during exhaling and prevents the filter from being contaminated, thereby extending the lifespan.
In terms of sanitization, again, we have two categories. Disposable N95 respirators are meant to be single-use. However, shortages have motivated hospitals to implement sanitization and reuse measures. For reusable N95 respirators, the mask surfaces should be cleaned periodically, with alcohol or soap and water.
Due to the current pandemic and the corresponding shortages of PPE or medical staff, sales of N95 respirators are only allowed to healthcare organizations.
Air Filtration Performance
Face Mask vs KN95 / N95 Respirator
How is the Woobi Mask Categorized?
The Woobi Plus and Pop are KN95 Certified reusable non-medical (consumer) respirator style pollution masks. That is a mouthful, but basically, it means that they filter >95% of all airborne particles and are compact, comfortable, and convenient. A large part of the comfort is due to their lightweight compared to their industrial counterparts. Filtration performance is similar to an N95 elastomeric half-face respirator. The sanitization process is also identical to the reusable N95. They are designed to protect the wearer from air pollution and other harmful particles.
What about UV-C Sterilization?
UV-C is a form a light wave radiation, and a particularly strong one. UV-C is a spectrum of light that can cause blindness and skin cancer by destroying the actual bonds the make up your DNA. UV-C light typically produces ozone, which can irritate the airways, especially on those that are already sick or have poor respiratory performance. There are new products in this space that claim to produce no ozone. We are anxious to see how they can achieve this new breakthrough in UV-C technology, and it sounds fascinating. However, until there is data that illustrates these masks are completely safe, we cannot recommend UV Masks.
What about Masks that promise 99.97%?
Masks with NIOSH certifications are tested and certified to perform at a reliable level for extended periods of time, under rigorous testing protocols. KN95 Certification is very similar, but the actual testing limits are different. Most consumer focused masks are not tested or certified at all. With no government agency or independent lab tests verifying their claims. We don't want to tell you that all masks that claim very high standards are not being completely transparent. But, we have seen a clear trend. The big issue here is fit, or rather the mask's ability to create a good seal with the face. Most consumer masks that claim 99% filtration will test the filter material itself, taped to a test machine, and not test the shape of the mask against the face. N95 and KN95 testing take into consideration the mask fit, and overall performance. Not just the materials in the filter. In fact, a recent study concluded that highly rated filters with poor fit performed about as well at protecting the wearer as a common surgical mask. Or, rather, not very well at all.
What about clear masks?
Transparent masks have become very popular lately, especially for professions who need to service the hearing impaired. If a mask filters well, it will contain moisture from your breath and require an anti-fog coating to remain visibly transparent. These types of coatings wear off and will need to be re-applied. We recommend looking into the safety of the anti-fog coating before deciding to purchase a clear mask. Definitely consider your desired filtration efficiency when choosing your mask. Many clear mask options have very low air filtration scores.
What Mask Should You Use?
The best answer here is to follow the current guidance of your local health agency. The recommendations are regularly updated or revised. Masks and respirators are tools that can help to keep you and your loved ones healthy. Misused, they can be harmful. It would be best if you modified your selected mask based on how risky your environment will be. For example, cloth masks may be sufficient for individual circumstances. Still, a respirator will provide a greater protection level when you feel that is necessary. If you feel unsure, we recommend purchasing more than one mask type so that you are always prepared. Remember, most masks focus on a specific function, so layering masks (like medical workers) can yield fantastic results.
Whichever mask you choose, make sure you follow the recommended usage instructions and cleaning protocols. Hopefully, you found this guide to be informative. If you did, please take a moment to share with family or friends.
