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What are face masks?

Face masks such as cloth or fabric masks act as a simple barrier and work as “source control”.

“Source control” refers to preventing the wearer’s respiratory droplets from traveling into the air and onto other people when the person wearing the mask coughs, sneezes, talks, etc.

These are not suitable for use during medical and surgical procedures in healthcare facilities, where exposure and risk of transmission of infection are higher. These masks may be used by the general public and in community settings. Please refer to MOH’s guidance and FAQs on the use of masks.

Face masks are not regulated as medical devices under the Health Sciences Authority (HSA). Therefore, the quality and effectiveness of face masks are not regulated by HSA.

How to choose a face mask?

For greater effectiveness, choose face masks that have good filtration capability. Examples of such masks include those distributed by the People’s Association and Temasek Foundation.

When selecting a face mask, look for the following specifications:

  • Masks with at least 2 to 3 layers of fabric. As a general guide, the material should not be see-through when held against the light.

  • Layers should preferably be made with different fabrics, including:

    • Water-repellant outer layer

    • Middle filter layer to remove particulates – this can be disposable filter inserts

    • Absorbent inner layer to absorb droplets from wearer’s mouth

  • Fabrics with better filtering efficiency

  • Fabrics with enough permeability to allow breathing

  • Appropriate fit around the face and chin, with complete coverage of the nose and mouth, to prevent leakage of exhaled droplets

Do not choose masks with exhalation valves, as these allow the escape of exhaled droplets from the wearer and expose others to the risk of infection.

Are face masks useful?

Disposable 3ply face mask with good filtering efficiency help prevent people who have COVID-19 from spreading the virus to others by acting as a “source control”. Wearing a mask in public places limits exposure to respiratory droplets and large particles and reduces the risk of community spread of infection. This is especially relevant for asymptomatic or pre-symptomatic infected wearers who feel well and may be unaware that they are infectious.

These masks are particularly useful in public settings (e.g. when using public transport) when strict adherence to safe distancing may be challenging.

As the contagious Delta variant of COVID-19 continues to spread in the U.S., you need to mask up—even if you're vaccinated. Here's how to find the right face mask for you.

What Are N95 Masks?

The N95 respirator is considered the gold standard of face coverings in the medical world, and even in the construction industry. These face coverings diverge from surgical masks in that the edges are designed to fit snugly to your face.

N95 masks are made of tough, yet flexible non-woven polypropylene fiber. They're mostly round with a protrusion near the top to help cover your nose. Elastic strings stretch around your head to hold the mask in place. N95s sometimes feature a valve to make inhalation and exhalation easier, but they're not required. The mask should be labeled with "N95" on it. Watch out for typos, as these could be counterfeits.

What Are KN95 Masks?

KN95s are closely related to N95s, but only the latter is approved for use in medical settings in the U.S., and the reasoning is pretty simple: N95s are the U.S. standard, while KN95s are the Chinese standard for these close-fitting filtration devices. Both are rated to filter out 95 percent of very small particles.

Due to the shortage of personal protective equipment (PPE) in the U.S. at the start of the pandemic, the CDC has authorized the use of KN95 masks as a suitable alternative for N95 masks. However, a number of hospitals and other KN95 wearers have pointed out some discrepancies in quality.

KN95 face masks are better than surgical masks or cloth masks, according to ECRI. These are most appropriate in cases where you don't expect to come into contact with bodily fluids. Non-certified masks that use head and neck straps will also serve you better than those with ear loops.

As the contagious Delta variant of COVID-19 continues to spread in the U.S., you need to mask up—even if you're vaccinated. Here's how to find the right face mask for you.

Disposable nitrile, natural latex, PE, and vinyl gloves, often referred to as thin-mil gloves, are used in a variety of distinct applications. Understanding the truths about glove performance is important in selecting the right glove for each application.

Myth #1: More Texture Means Better Grip

One of the most common misconceptions about disposable gloves is that more texture results in better grip. In fact, texture has very little effect on grip. It is possible to make an extremely textured glove with a low grip and a smooth-surfaced glove with a high grip.

Surface treatment is the most significant factor in the grip level of a glove. Natural latex is inherently sticky, or tacky, much like glue. Without proper processing, natural latex sticks together like a large ball of adhesive. To reduce this tack, the surface must be treated. The most common surface treatments are surface chlorination and coating. Chlorination changes the surface properties and creates a hard, lower-tack shell around the glove. Coating technology adds a new, lower-tack layer to the glove.

Reality: Surface tack, or grip, can be controlled by the level of chlorination or the characteristics of the coating.

Myth #3: Gloves Can Be '100%' Nitrile, Natural Latex, or Vinyl

Glove suppliers frequently claim glove composition of "100%" of the respective materials. Without additives, it is practically impossible to produce a usable glove of any of these materials. Adding curatives, cross-link agents, and accelerators to nitrile and natural latex is essential to making a strong, durable glove. Vinyl requires plasticizers and activation agents. Surfactants, which help with film formulation, are another additive found in most gloves. Formulations typically require 4-10 percent of additives to make a good glove.

Reality: Claims of "100%" nitrile, natural latex, or vinyl are not accurate.

Myth #4: Fillers Always Diminish Glove Performance

Fillers are used broadly in gloves. Most manufacturers use or have the ability to use fillers to help reduce the cost of making a glove. Fillers are often difficult, but possible, to detect through advanced technologies such as Thermal Gravimetric Analysis.

Fillers help to reduce the cost of a glove and, up to certain amounts, actually can improve specific performance characteristics. For example, tear strength is significantly improved in natural disposable latex gloves when a moderate amount of calcium carbonate is added. The keyword is "moderate." Fillers up to about 15 percent are tolerable; anything above that can become detrimental to the performance and quality of the glove in use. Some manufacturers have experimented with up to 50 percent filler, with limited success.

Even within the same material, there are significant differences from manufacturer to manufacturer. Other factors influencing glove performance are raw materials, formulation, process, and washing. These vary significantly from glove to glove and can result in performance differences in most applications. Typically, standards for the different materials also are not harmonized. ASTM exam glove standards have different tensile strength requirements for latex, nitrile, and vinyl. Vinyl has the most relaxed strength requirement, followed by nitrile, while latex has the highest tensile strength requirement of the three, and disposable PE gloves can withstand strong pulling and are not easy to break.

The CDC recommends that healthcare personnel put on a clean protective suit upon entry into the patient room or area. However, if coveralls are used as an alternative to gowns, the CDC also recommends that healthcare workers put on a clean garment before performing patient care, with a new coverall required for each patient. 

Should protective suits be worn when testing for the coronavirus?

In its guidance on the appropriate use of testing for smart healthcare providers, the CDC recommends PPE that includes a gown for baggers and swabbers. Specimen transporters need only a glove and facemask.

Similarly, gloves and facemask (if more than 6 feet from the person being tested) are required for the registrar and labeler responsible for registration, consent form and labeling the test kit.

In addition, all participants undergoing testing should wear a facemask or cloth face covering throughout the process, only removing it during swabbing. All masks must be produced by professional mask making machine and in strict accordance with hygiene standards.

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