Surgical masks are currently one of the most popular items around the world since many people are using them for protection against the COVID-19 pandemic in the United States. Not only are regular people using them, but healthcare centers are also experiencing an increase in their demand as they’re part of the personal protective equipment (PPE) necessary for the protection of frontline workers. In this article, we’ll go through the process of manufacturing these valuable masks.
First, let’s talk about what exactly is a surgical mask?
These are disposable face masks with multiple uses in the healthcare field. They’re pretty easy to recognize, with almost always a blue and white color scheme and earloops, frequently being used by surgeons and other physicians, dentists, nurses, paramedics, and other types of healthcare providers.
Their main protective function is as a physical barrier against fluids released during procedures, as they have a resistance to fluids that is much higher than other face masks available in the USA, including reusable cloth masks and KN95 masks. This is important during certain medical procedures since contaminated fluids can be released at high pressure during them.
Surgical masks also have a certain degree of filtering abilities, but they can only filter out large particles like bacteria but not viruses. For virus protection, including the flu or COVID-19, the highest antiviral filtering properties are found in N95 respirators, which are considered the best option in healthcare settings during the pandemic.
Some of the most popular N95 masks are the 3M N95 masks, with models like the 3M 8511, 3M 8210, and 3M 1860 being some of the most purchased ones. These masks have uses outside the healthcare field too, as they can filter out other particles like dust or smoke.
As disposable face masks, they are not meant to be reused or shared with other people. After being used, or if the mask becomes wet, dirty, or damaged, removing it and replacing it with a new one is very important. To handle them, washing the hands before and after is recommended, and it should always be done by the ear loops or straps, as touching the inside or outside of the facepiece can contaminate the mask or the hands.
How are surgical masks manufactured?
Like N95 masks and other types of disposable face masks, surgical masks are made with a material called non-woven fabric, which is made with a plastic that most commonly is polypropylene, but other ones can be used as well, like polyethylene, polystyrene, polycarbonate, or polyester.
This fabric allows better bacteria filtration and air permeability than regular woven cloth fabrics. To make the 20 gsm material, the plastic used is melted and then put through a process called “spun bonding”, where the melted plastic is extruded in a web into a conveyor belt. For the 25 gsm material, a different process called melt-blowing is used, where hot air through multiple nozzles with a very small size makes the melted plastic be extruded, becoming tiny fibers that bind after they cool down on a conveyor. These will have a less than a micrometer diameter.
Surgical masks usually have multiple layers, each with a specific function. In general, a layer of textile fabric is covered with 3 non-woven layers on each side. Each of these layers has a function: the most external one is fluid-resistant, the middle one is the filtering layer, and the most internal one is absorbent.
The filtering layers are placed there to filter out particles with a size larger than one micrometer, such as bacteria. However, the level of filtration efficacy will depend on many factors, such as how the fibers were manufactured, the web structure, and the shape of the fibers, and how they’re cross-sectioned.
This is how each layer is made, and then they are ultrasonically welded together on a machine line. In the same machine, ear loops, nose strips, and other additional pieces are stamped too. The last step before being packaged and shipped off is sterilization.
Surgical masks are medical devices that have to be regulated and approved by the Food and Drug Administration (FDA). So, after the masks are done, they need to be tested by them to ensure their efficacy and safety in different healthcare settings. The five tests they have to be put through are:
- Fluid resistance: this test makes sure fluids won’t penetrate the mask and be in contact with the user’s mouth or nose when they’re released into the environment at high pressures like for example blood coming out of a punctured human artery.
- In vitro bacteria filtration efficiency: this test ensures that the mask can filter out the appropriate percentage of bacterial particles.
- Particle filtration efficiency: this is done to make sure the mask will filter out particles with the appropriate size
- Flammability: since many elements in operating rooms can cause a fire, this is done to make sure the mask won’t catch on fire.
- Breathing resistance: comfort and breathability are important for workers with long shifts, and this test ensures the proper ventilation, and it also ensures the mask will hold its shape while the wearer breathes.
Surgical masks are one of the most important items for healthcare facilities right now. But, due to the COVID-19 pandemic, many of these supplies, including not only surgical masks and other medical-grade masks, but also face shields, gloves, and gowns, are scarce and shortages are being reported all over the USA.
Hospitals need to buy these items in bulk and wholesale, but this is difficult since many of them have become very difficult to find for sale in either physical or online stores. For this reason, the Centers for Disease Control and Prevention (CDC) recommends the use of reusable cloth masks in both adults and kids over the age of 2 for protection.