Face Masks, explaining the differences

With the recent Government guidelines to wear a mask on any public transport and preferably whenever we go outdoors, along with the need to wear suitable PPE while using a Disinfectant Fogging Machine, on building sites or carrying out duties in the care and medical market, it is important that we know what level of protection is required.

Surgical Type llR Masks and general purpose 3 ply masks

A surgical mask is a loose-fitting, disposable device that creates a physical barrier between the mouth and nose of the wearer and potential contaminants in the immediate environment. Surgical masks are regulated under 21 CFR 878.4040. Surgical masks are not to be shared and may be labeled as surgical, isolation, dental, or medical procedure masks. They may come with or without a face shield. These are often referred to as face masks, although not all face masks are regulated as surgical masks.

Surgical masks are made in different thicknesses and with different ability to protect you from contact with liquids. These properties may also affect how easily you can breathe through the face mask and how well the surgical mask protects you.

If worn properly, a surgical mask is meant to help block large-particle droplets, splashes, sprays, or splatter that may contain germs (viruses and bacteria), keeping it from reaching your mouth and nose. Surgical masks may also help reduce exposure of your saliva and respiratory secretions to others.

While a surgical mask may be effective in blocking splashes and large-particle droplets, a face mask, by design, does not filter or block very small particles in the air that may be transmitted by coughs, sneezes, or certain medical procedures. Surgical masks also do not provide complete protection from germs and other contaminants because of the loose fit between the surface of the mask and your face.

Surgical masks are not intended to be used more than once. If your mask is damaged or soiled, or if breathing through the mask becomes difficult, you should remove the face mask, discard it safely, and replace it with a new one. To safely discard your mask, place it in a plastic bag and put it in the trash. Wash your hands after handling the used mask.

The general purpose 3 ply mask is perfectly adequate as a face cover for going shopping and out on public transport.

N95 Respirator

An N95 respirator is a respiratory protective device designed to achieve a very close facial fit and very efficient filtration of airborne particles. Note that the edges of the respirator are designed to form a seal around the nose and mouth. Surgical N95 Respirators are commonly used in healthcare settings and are a subset of N95 Filtering Facepiece Respirators (FFRs), often referred to as N95s.

The similarities among surgical masks and surgical N95s are:

  • They are tested for fluid resistance, filtration efficiency (particulate filtration efficiency and bacterial filtration efficiency), flammability and biocompatibility.
  • They should not be shared or reused.

Comparing Surgical Masks and Surgical N95 Respirators

The FDA regulates surgical masks and surgical N95 respirators differently based on their intended use.

Picture of a surgical mask

surgical mask is a loose-fitting, disposable device that creates a physical barrier between the mouth and nose of the wearer and potential contaminants in the immediate environment. These are often referred to as face masks, although not all face masks are regulated as surgical masks. Note that the edges of the mask are not designed to form a seal around the nose and mouth.

An KN95 respirator is a respiratory protective device designed to achieve a very close facial fit and very efficient filtration of airborne particles. Note that the edges of the respirator are designed to form a seal around the nose and mouth. Surgical N95 Respirators are commonly used in healthcare settings and are a subset of N95 Filtering Facepiece Respirators (FFRs), often referred to as N95s.

Filtering facepiece respirators (FFR), which are sometimes called disposable respirators, are subject to various regulatory
standards around the world. These standards specify certain required physical properties and performance characteristics in
order for respirators to claim compliance with the particular standard. During pandemic or emergency situations, health
authorities often reference these standards when making respirator recommendations, stating, for example, that certain
populations should use an “N95, FFP2, or similar” respirator.
This document is only intended to help clarify some key similarities between such references, specifically to the following FFR
performance standards:
• N95 (United States NIOSH-42CFR84)
• FFP2 (Europe EN 149-2001)
• KN95 (China GB2626-2006)
• P2 (Australia/New Zealand AS/NZA 1716:2012)
• Korea 1st class (Korea KMOEL – 2017-64)
• DS2 (Japan JMHLW-Notification 214, 2018)
As shown in the following summary table, respirators certified as meeting these standards can be expected to function very
similarly to one another, based on the performance requirements stated in the standards and confirmed during conformity
testing.
One notable comparison point is the flow rates specified by these standards for the inhalation and exhalation resistance
tests. Inhalation resistance testing flow rates range from 40 to 160L/min. Exhalation resistance testing flow rates range from
30 to 95 L/min. Some countries require testing to be performed at multiple flow rates, others at only the high or low end of
those ranges. Although this appears to suggest that the standards’ requirements for breathing resistance (also called “pressure
drop”) differ from each other, it’s important to understand that pressure drop across any filter will naturally be higher at
higher flow rates and lower at lower flow rates. Given typical pressure curves for respirator filters, the standards’ various
pressure drop requirements are actually quite similar. This chart shows a representative filter pressure drop curve. If one
filter is tested at a high flow rate, the pressure drop performance will be relatively high. If that same filter is tested at a low
flow rate, the pressure drop performance will be relatively low.