Despite the near-constant discussion of them lately, many individuals still don’t have a complete understanding of surgical masks and their purpose. Simply put, a surgical face mask is a piece of protective equipment that creates a physical barrier against airborne particles that can be either hazardous like viruses or irritating like dust.
It covers the mouth and nose in an attempt to keep the respiratory passage safe and isolated against any foreign particles and droplets entering the lungs. It also works to protect surgical patients (and, in the case of the coronavirus epidemic, members of the community) from droplets released by the wearer of the mask. To ensure breathability, surgical masks are made of different materials, some being disposable after single-use and others for extended usage.
Surgical masks were introduced in the late 1800s, initially for medical caregivers of tuberculosis patients, and later on for the influenza pandemic of 1918 (also known as Spanish Flu) to protect the wearers from the infections of the deadly airborne virus. However, the masks used during that time weren’t nearly as sophisticated as what we are accustomed to today.
Need for surgical face masks
The importance placed on the usage of surgical face masks has gradually increased in the context of deadlier viruses springing in recent history. Until the late 1990s, a lot of debate went on whether medical caregivers or the patients should be wearing surgical face masks. The general acceptance of the fact that surgical masks play a big role in the prevention and control of the spread of viruses, especially in post-operative care, remains widespread.
Since the COVID-19 pandemic, there has been an acute shortage of surgical face masks due to widespread panic buying. People have been forced to design and stitch custom face masks, which has given rise to a whole new industry of surgical mask fashion. There is a range of decorative surgical masks made of different fabrics, designs, and brands (with varied efficacy against COVID-19).
Evolution of face masks
Among the first surgical face masks were simple rolls of gauze (or a handkerchief) tied around the nose and mouth. The earliest known use of this was in the late 1800s to avoid any respiratory fluids or droplets affecting a patient in surgery. More than a century later, the evolution of surgical face masks has been rapidly assisted by the advanced technology leading to micron face masks and respirators.
A typical surgical face mask consists of three to four layers of non-woven fabric, with two filters to block bacteria or viruses down to one micron. The disposable variety of surgical face masks are most effective for up to four hours. (For comparison, N95 respirators are effective for down to 0.3 microns and worn until the filter becomes clogged and unbreathable.)
The material used to make surgical face masks is polypropylene (20-25 grams/square meter in density). It is more effective than woven cloth because of its breathability, filtration of aerosols, and non-slippery texture.
Performance of surgical face masks
There are six distinct properties to measure the performance of surgical face masks, as stated below:
- Fluid Resistance: Tests measuring the amount of fluid a cover can withstand.
- Bacterial Filtration Efficiency (BFE): Bacteria of a specific size are projected through the mask into a sieve sampler at a specified concentration and flow rate. A higher percent efficiency equals a more effective mask (minimum of 95% BFE recommended).
- Particulate (Submicron) Filtration Efficiency: Minute particles, for example, diathermy smoke, are measured being drawn through the mask at a specific concentration and rate. Higher resistance to particles equals a more effective mask. The efficiency of 95% is expected, although venting can occur.
- Pressure Drop: Test of breathability where the air is passed through the mask at 50 liters per minute, and the resistance to airflow is measured. The higher the strength, the more excellent resistance to breathing.
- Flammability: Measurement of time taken for a flame to move across mask material in controlled conditions. A rate of flame spread of greater than four seconds is the standard.
- Biocompatibility: The mask must be non-irritating to the skin. Tests for cytotoxicity, skin sensitization, and dermal irritation should be negative.
In addition to the features mentioned above, some general considerations need to be made while purchasing surgical face masks.
- Type: If you are not suffering from an infection or showing symptoms but just want protection from airborne particles, go for a simple face mask. Reserve N95 respirators for sickness or critical use, i.e., where the risk of contracting or transmitting the infection is high.
- Size: Make sure the mask fits your face perfectly.
- Life: Every face mask has limits as to how long you can effectively wear it. Some are effective for a few hours, others for a day at most. You should replace the mask after eight hours or less because bacteria and germs accumulate on its surface. Discard your mask even earlier if you have been in mass gatherings. For N95 respirators, read the instructions on how often the filter should be replaced.
- Hygiene: Wash and dry your hands before wearing a mask, and once worn, do not touch it repeatedly. Once back in the house or in a secure place, dispose of the mask and wash your hands.
Should I use a mask with a vent?
While a mask that has a vent on the front can help make breathing easier for you, it allows your own breath to escape the mask. That means if you are infected (even if you are asymptomatic), it is believed that you could still infect others through that vent. Though some recommend covering the vent with tape, it’s really best to steer clear of the vents altogether, just to be sure.
Best surgical face masks in the market
Although a surgical face mask does not guarantee complete protection against the spread of aerosol infectious particles, it is still better than having no protection at all. In the COVID-19 pandemic, it becomes even more critical to exercise social distancing and effective self-care protocols to minimize the risks of contracting and spreading the disease to immediate family, friends, and the general public. The following is a list of medical-grade face masks to be considered.
3M is a leading company to manufacture high-quality medical equipment and respirators. In their N95 series, the 8210 Particulate Respirator filters out airborne particles with higher efficiency, which is why it has been NIOSH approved. It has a microfiber media filter, an adjustable nose clip, and a tight fit to reduce wiggling.
Another from the highly coveted N95 series by 3M, the 1860 Medical Mask’s desirability stems from its focus on medical usage. This face mask, cleared by the FDA for surgical use, has particulate filtration and an effective barrier against certain bacteria and viruses. It has a solid shape that stays in its place for more prolonged use, although before buying, you need to ensure that the manufacturing date is within the last three years due to its relatively short shelf-life.
Cardinal Health provides surgical face masks specifically for medical caregivers and to be used in the hospitals, specifically operating rooms. The ASTM Level 3 surgical mask has the highest bacterial and sub-micron particulates filtration efficiency (at 0.1 microns) of 98%. It has four-layer construction, a plastic-laminated nose wire, fluid protection, and surgical ties to secure it snuggly.
This is a cost-effective variety of Cardinal Health surgical face masks called ASTM Level 1. It is designed for general use by medical caregivers with relatively lower fluid protection than the previous Level 3 variety. The ASTM Level 1 surgical mask has bacterial and sub-micron particulates filtration efficiency (at 0.1 microns) of 95%. It is available in different colors, with a distinctive white pediatric print designed to be child-friendly, along with a plastic-laminated nose wire and surgical ties to secure it snuggly.
Henry Schein Medical provides a vast range of medical and surgical masks being a leading distributor to specific health care providers. With the product range including ear loops, molded, surgical, respirator, and N95 face masks, they also provide face shield masks with varying degrees of fluid resistance (ASTM Levels 1, 2, 3), bacterial filtration, anti-fog (in case of visors), latex-free material, and cellulose inner lining.
Medline Industries is both a manufacturer and distributor of medical equipment and supplies to healthcare providers, which means an efficient supply chain. One of their leading products is the CURAD Biomask with 99.99% viral filtration (specifically influenza viruses) inactivating 99.99% of tested influenza viruses within five minutes of direct contact with the mask’s surface.
It is made of hydrophilic plastic coating that absorbs airborne droplets away from the outer surface of the face mask and is latex-free. This has been tested for specific seasonal flu viruses, along with pandemic H1N1 flu, avian flu, swine flu, and equine flu, and works on the principle of creating a low pH environment in the outer active layer of the face mask. This high barrier surgical face mask has two inner layers made of different compounds to keep the viruses away from the outer layer.
Another effective surgical face mask by Medline Industries is the yellow-colored isolation face mask with ear loops. It has a high bacterial filtration efficiency of 98% and particulate filtration efficiency of 97%. It is made of latex-free yellow polypropylene, spunbond polypropylene, and cellulose. With a wide nosepiece, this surgical face mask is light and comfortable to use while maintaining proper fit and breathability.
Halyard surgical face masks have a broad range of features and levels of protection, with most of the materials being sonically bonded. These protective face masks have a three-layer construction and are latex-free. With a comfortable nosepiece, it snugs onto the facial contours in an efficient manner and is available in pleat or pouch styles. They have a high bacterial filtration efficiency of 98% and particulate filtration efficiency of 97%.
Surgical masks and social distancing
The use of surgical face masks primarily prevents cross-contamination in a medical facility. It is considered a critical part of the personal protection equipment (PPE). But with the recent spread of COVID-19 pandemic, the public use and panic buying of these masks have created critical shortages in some areas. It is advised that, instead of merely hoarding and wearing a face mask, the general health and safety guidelines provided by the local healthcare experts, such as strict social distancing, be heeded as well.
If non-healthcare workers are able to make or order a reusable mask, it is best to do so in order to allow as many surgical masks to make their way to front line workers as possible.