There are many jobs that have a high risk of infection, and dentistry is a great example. Dentists work on the mouth, a part of the body that can carry plenty of bacteria. Dentists’ job is to keep the teeth and the mouth clean, but they need to keep themselves clean as well.

When you’re choosing a face mask for your dental procedures, you probably realize that you need to pick the best type for the job. Don’t buy the first mask you see in a store; it may not be good enough for the job.

Instead, you have to find the right level of mask. In this post, we will look at level 3 masks, along with other types of masks, and see which ones are right for the job.

What Are The Three Mask Levels?

You may be wondering what the three levels of masks are, and which you should pick. First, let’s give a summary of each level.

Level 1

This is a mask that has a low barrier of protection. If there are low amounts of fluids during a procedure, having this mask handy may help you due to its affordability. It’s much easier to buy this mask, especially in bulk.

However, if there are sprays, fluids, or aerosols around, you may want to think twice before you use this mask. It will not provide you with enough protection, and you may end up feeling sick if you wear this to a long operation.

What is a Level 1 Mask Used for?

There are some situations where a level 1 mask is all you need. If you’re a dentist, you may use a mask when you are examining, having impressions done, doing lab work, or just performing general orthodontics. For these activities, a level 1 mask will work splendidly and anything higher will be overkill.

Level 2

Level two masks offer moderate protection. If you’re performing a procedure in an area that has moderate amounts of fluids and sprays, you may want to put this one.

What is It Used for?

A level 2 mask is good for several procedures. When you are performing a prophylaxis, sealing teeth, or having brief oral surgery, a level 2 mask is just right for that. Some people may put on a level 3 mask because they feel like it’s better safe than sorry, but a level 2 mask should work just fine.

Level 3

An ASTM level 3 surgical mask provides the highest protection barrier. When you are in an area with high amounts of fluids, you may want to put on this mask. It’s the priciest, but you get what you pay for. Protection against fluids is the main appeal of a level 3 mask, because it otherwise offers similar protections to level 2. However, plenty of fluids tend to happen during an operation, so having an ASTM level 3 mask for this can be important.

What’s It Used for?

This is a high-barrier for a reason. If you’re performing a procedure where you expect there to be lots of fluids, splattering liquids, and aerosols, you will want to put on a level 3 mask. When you are using an air polisher, put on the mask. If you have to perform complicated oral surgery, put it on. Putting on a mask that is a lower barrier can be dangerous.

We should probably mention that these masks are not intended for vapor protection. Even the highest graded mask doesn’t offer that. If you need protection against any vapors, you should use a respirator. Whether you’re trying to protect yourself from dust particles or something similar, an N95 respirator can help you with that.

Finding the Rating

If you have a mask and you are unsure whether or not it’s a level one, two, or three, how can you figure that out? On the package, there should be an ASTM rating of 1, 2, or 3.

What is the ASTM? It’s the American Society for Testing and Materials. They created the mask definitions that are used by dental professionals, and most masks have a rating by them. Not all masks have ratings, so you need to make sure the mask is equal, or just look for a mask with an ASTM rating on it.

Obviously, other countries may use different ratings for their mask protection. This article is focused on American dentists. If you’re in another country, do research on the mask ratings in that area and find a mask that has a rating that’s appropriate. You’ll be glad that you did.

When buying an ASTM level 3 mask online, it’s easier. For example, with an ASTM level 3 mask, Amazon should tell you in the title what level it is. Always double check though.

How Are They Tested?

You may wonder how these masks are tested in order to have their rating. What factors are used? When putting on a mask, it’s definitely valid to wonder how the rating came to be. Masks are tested in several areas. Let’s take a look at what they are.

Bacteria Filtration

A mask needs to filter bacteria in order to be effective. A mask’s filtration is tested by seeing how much bacteria that’s over 3 microns in size is filtered out. One bacteria that is used is Staphylococcus aureus. This is a bacteria that is found in the upper respiratory system.


This is a test that measures how a mask resists airflow. When testing a mask, the pressure is tested. Then, controlled air is blown on it and the pressure is measured again. The difference is then divided by the sample’s surface.

Lower resistance means that the mask will feel more comfortable to wear. If you are performing surgery, you probably want a mask that is more comfortable to wear, especially during long periods.

Breathability is measured in mm H20. A level 1 mask will have a measurement of <4 mm H20. A level 2 will have a measurement of < 5 mm H20, along with a Level 3. Only level 1 is less breathable, it seems.


Testing for flammability involves putting the material up to a flame and seeing how long it will take for it to burn. There are different classes of flammability, with class 1 meaning that it’s normal. All masks tend to be a class 1, which is what’s normal for clothes.

Fluid Resistance

The big draw of a level 3 mask is that it’s able to resist quite a lot of fluids. When tested for resistance, synthetic blood is thrown at the mask at a quick velocity. If there’s any evidence of blood penetration, it’s not a level 3 mask.

Particle Filtration

This is similar to the bacteria test, but instead of 3 microns, particles that are bigger than 1 micron are tested. These tests tend to involve latex aerosol in a chamber designed for testing. A level 3 mask should pass this test in flying colors.

Aerosol particles tend to be quite small, so a good mask will be able to filter all of it out without you having to worry about breathing.

Why Level 3 is Such a High Barrier

Now that we listed what level 3 is and what it’s used for, let’s dive deeper into this particular mask. You may wonder why level 3 is so good for procedures that have high amounts of fluids and sprays. Here are a few reasons why.

It Resists the Most Fluids

Fluid resistance is measured in mmHg. Level 3 masks have 160 mmHG of fluid resistance, which is double the rating that level 1 has. Level 2 sits in-between at 120 mmhg.

It’s Breathable

Both level 2 and 3 offer the same amount of breathability at <5 mmH20 while level 1 has 4. When it comes to ASTM level 1 vs. level 3, level 3 just feels more comfortable. It’s always important to have a comfortable, breathable mask, especially if you are in a procedure where you will have to be wearing it for a long time.

It Filters Particles

Both Level 2 and Level 3 filter around 98 % of particles at 0.1 micron, while level 1 masks filter out at 95 percent. In the battle of ASTM level 1 vs. 3, level 3 has an edge for sure.

You may notice that level 2 and level 3 masks are equal in many ways except for fluid resistance. Therefore, the main barrier that level 3 masks have is that they are great for when the surgery you are performing has fluids flying everywhere. In many dental procedures, this tends to happen, so having a level 3 mask is important.

However, It Doesn’t Provide Respiratory Protection

A level 3 mask can protect against bacteria, but it doesn’t offer total respiratory protection against viruses. Because of this, you will need an N95 respirator for the job. Wearing any of these masks in public can still help reduce your chances of getting a virus, but only a respirator can provide the most protection. When wondering who wins in the battle between ASTM level 3 vs n95, just know it depends on use.

It Is Pricey

This is the most expensive mask out of all of them, so you may want to use it only when the situation is appropriate. If you buy in bulk, you may be able to save. With that said, don’t fall for masks where the price appears too good to be true. Sometimes, you may end up with a mask that doesn’t work because of it.

Getting the Most Out of Your Mask

When you do put on a level 3 mask, you are getting the most protection against liquids. However, if you do not obey the following guidelines, your mask may not be as useful as it’s supposed to be. Here are some ways you can get the most out of your mask.

Wearing it Right

First, you have to wear your mask right. Many people forget to put their mask over their nose. With a level 3, your mask needs to be put over your mask, your nose, and your chin. Also, you need to make sure the front and back are facing correctly.

Change Masks

A single mask is not going to last you all day. In fact, you should be changing your mask once a patient. If you’re in an area where there are high amounts of aerosols, you need to change your mask once per 20 minutes. Staying too long can break down the mask’s protections, rendering it useless.

Wear Other Protection as Well

Besides a mask, you should be wearing other protections as well. For example, you should have a gown, gloves, glasses, and anything else that is appropriate for surgery. This should be quite obvious, but many people tend to forget to come to the operation fully protected.

Always Have the Right Rating

We can’t stress this enough. Before you put on the mask, read the ASTM rating and make sure it’s level 3. If you’re going to be in a procedure where you expect high levels of splatter, fluids, or aerosols, then you will need a level 3 mask. For moderate levels, a level 2 should be what you need. It’s better to overestimate how much protection you need versus going in with little protection at all. With that said, don’t spend too much on masks when you're in a situation where a level 1 will suffice.

As we mentioned, ASTM ratings can help, but not all masks will have those ratings. At the end of the day, it’s up to you to do the research and make sure the mask will fit the situation.


It’s always important to pick the correct face mask for whatever procedure you are performing. In 2020, masks can be pricey, especially an ASTM level 3 face mask. However, they are worth the money. If you pick a level that’s lower for the job you need, you may be infected.

Level 3 masks provide the highest barrier towards fluids, splatter, and aerosol. Because of this, always put one on if your procedure will have any of that. It’s better to be safe than sorry. However, if your procedure is low-level, then wearing a level 1 or 2 mask is right for the job.

Always check the grade of the mask you are buying to make sure it has an ASTM grade that is right for you. You will be glad you did.