2026-07-20
Understand and Choose the Right KF Mask Grade!
Learn about KF (Korea Filter) mask grades, their filtering efficiency, and how to choose the best mask for protection against fine dust and respiratory viruses like COVID-19.
This is Gangnam Smile Eye Clinic, dedicated to bringing back your happy smiles and the joy of seeing.
Recently, there's been a significant increase in people wearing masks in public places and on the streets, hasn't there?
Interest in masks has grown so much that it has led to a mask shortage.
Let's find out what KF means and the differences between each grade at Smile Eye Clinic.
◆ KF Grades
KF (Korea Filter) signifies that the mask has been certified by Korea's Ministry of Food and Drug Safety (MFDS).
It is evaluated with stricter standards than those of the US National Institute for Occupational Safety and Health (NIOSH).
There are a total of three KF grades, and the higher the number, the better the mask filters dust.
◆ Effectiveness of Masks by KF Grade
KF80 grade: Filters approximately 80% of 0.6㎛ particles.
KF94 grade: Filters approximately 94% of 0.4㎛ particles.
KF99 grade: Filters approximately 99% of 0.4㎛ particles.
Since KF94 and KF99 can filter 0.4㎛ particles, they are effective in filtering fine dust and
particles from respiratory illnesses such as the novel coronavirus.
Therefore, to prevent the novel coronavirus, wearing KF94 or KF99 graded masks is recommended.
When choosing a mask, just as important as the KF grade is confirming that it is officially approved by the MFDS.
Even if a mask has promotional text claiming to block fine dust, if it doesn't have the KF mark,
it is not a mask certified by the MFDS, so you must check for the KF mark.
Be sure to take care of your respiratory health from the novel coronavirus and fine dust!
Smile Eye Clinic will reliably protect your eye health!
Frequently Asked Questions
What does KF mean?
KF stands for ‘Korea Filter’. It means that the mask has been certified by Korea's Ministry of Food and Drug Safety (MFDS) and is evaluated with stricter standards than those of the US National Institute for Occupational Safety and Health (NIOSH).
What are the differences between KF mask grades?
There are a total of three KF mask grades. The higher the number, the better the mask filters dust. KF80 filters approximately 80% of 0.6㎛ particles, KF94 filters approximately 94% of 0.4㎛ particles, and KF99 filters approximately 99% of 0.4㎛ particles.
Which KF mask is best for preventing the novel coronavirus?
For preventing the novel coronavirus, wearing a KF94 or KF99 graded mask is recommended. Masks of these grades can effectively filter 0.4㎛ particles and respiratory disease particles.
Is there anything else to check besides the KF grade when buying a mask?
Yes, just as important as the KF grade when purchasing a mask is confirming that it is officially approved by the Ministry of Food and Drug Safety (MFDS). Masks without the KF mark are not MFDS-certified products, so you must always check for it.
Does a KF80 mask also block fine dust?
Yes, a KF80 mask filters approximately 80% of 0.6㎛ particles. However, for blocking fine dust and novel coronavirus particles, KF94 or KF99 grades are more effective.