Dust mask, N95 mask, or Respirator mask

Dust Mask, N95, or Respirator

Dust mask, N95 mask, or Respirator mask

What is the difference between an ordinary dust mask, N95 mask, and respirator? The answer is important to understand.

First, a dust mask is used where particles in the air such as ordinary dust, dust from wood, concrete, construction dirt, drywall, fiberglass and other materials are present. The dust mask helps to protect the person’s lungs from damage caused by inhaling these particulates.

A dust mask will have its limitations and will be effective only under specific use conditions.

The way it works is simple in that the filter action occurs when the wearer inhales. The paper or fabric filtering material is the mask itself, which can be folded or cup-shaped, with one or two straps holding it to the nose and mouth. Some may have an exhale valve that allows heat and humidity to escape between the face and the mask. A dust mask is designed to be disposable and should not be reused.

The National Institute for Occupational Safety and Health (or NIOSH), is an organization who recommends dust mask specifications.

A dust mask is described with a letter designation and a filtering efficiency.

The letters N, R and P indicate the mask’s resistance to oil degradation. The absence of oil particles in the environment allows use of N-, R-, or P-series dust masks. The presence of oil particles requires use of an R- or P-series filter.

Filtering efficiency is expressed as percentages of 95, 99, or 99.97. A mask with a 99.97 percent efficiency rating allows less particle leakage than one rated 95 percent. The amount of acceptable filter leakage determines face mask selection.

Dust masks (including the often mentioned ‘N95’) are a cheaper, lighter, and possibly more comfortable alternative to respirators, but may not provide as much protection, and may be more susceptible to misuse or poor fit.

A dust mask, and N95 type mask, will leak. They are not fit tightly to your face and WILL allow a certain amount of unfiltered air into your nose and mouth while you inhale. A common misconception is that since N95 surgical masks may be used by health care workers or doctors in an operating room, that it must be okay for protection. In fact, the wearing of the surgical mask by the health care provider, doctor or surgeon is protecting the patient from the doctor’s own breath (sneeze, cough, germs, etc.). While there is a level of protection for the wearer in a healthcare environment, to truly protect one’s self from virus or other airborne chemical contamination, you need a respirator mask that is fitted to your face for an air-tight seal with appropriate filtering.

Having said that, one might think that you are getting ‘some’ protection while wearing a N95-rated well fitting dust mask in a public environment, where it is suspected that people may be contaminated with a given contagious virus. This is likely true to an extent, and better than nothing for sure. However you should not make the mistake of believing that you are completely protected. Observe how the ordinary (and even the better fitting) dust masks will have gaps between the mask and skin. It is not air-tight and therefore not blocking 100% of the air that you inhale.

In summary, know your purpose and have the right mask for the right job. For casual protection, the ordinary dust mask may protect you from ordinary particles in the air. A N95 type mask will filter smaller particles and will provide a certain level of protection in some environments. A respirator will provide the ultimate protection due to its tight seal to your airways, while the filter being used in the respirator will determine the particulate protection. It seems that having all three would be useful to the prepper, and cover the range of circumstances that one might expect to encounter.


  1. Filter Efficiency:
    N95 (95%)
    N100 (99.97%)

    Filter Series:
    N (Not resistant to oil)
    R (Resistant to oil)
    P (oil Proof)

    The selection of N-, R-, and P-series filters depends on the presence or absence of oil particles, as follows:

    If no oil particles are present in the work environment, use a filter of any series (i.e., N-, R-, or P-series).

    If oil particles (e.g., lubricants, cutting fluids, glycerine, etc.) are present, use an R- or P-series filter. Note: N-series filters cannot be used if oil particles are present.

    If oil particles are present and the filter is to be used for more than one work shift, use only a P-series filter.

    P100 Respirator

  2. Those who have beards, will not get a proper seal with any of the above–

    1. Most manufacturers of respirators do indicate that a beard must be shaven to ensure a proper seal. Thanks for bringing up the point…

  3. you need to be tested (spirometry tested at a Dr. office)to wear and use a respirator. your lungs have to be functional enough to handle said respirator. It is NOT an easy test. Not knowing if your lungs have the capacity for a respirator is dangerous. Do your homework first. peace, shadowfaxhound

  4. I worked as a RN for almost 20 years. Having said that to say this. We use the N95 mask to go into TB rooms and such to protect ourselves BUT… You must be fit tested and know how to PROPERLY wear one. They come in sizes.

    To be fit tested you put on the mask, then a chamber is placed over your head and shoulders, then a substance of some kind (I am not sure what exactly what is used) is wafted into the chamber. If you can smell it then it is not the proper size. When you can not smell the substance then you have the correct size that is not allowing any particles to escape under the sides of the mask.

    The correct way to wear one is this: The elastic straps are pulled tightly so that they make a tight seal with the mask. The aluminum nose bridge is pressed firmly around your nose. If you have it on correctly it will make marks on your face.

    The face MUST be clean shaven in order to get a proper seal.

    1. Thanks Christine. Makes sense… In addition, I’ve tried a few varieties of N95 masks over the years, and some of them just don’t fit very well, although I have found others that do. The important thing is (as you said), a proper fit.

    2. Good points Christine but typically, in a hospital environment, surgical masks are used more generally to protect the patient from the caregiver’s exhalation, coughs, sneezes, etc…

  5. Which respirator will you most recommend for me while working with cobalt catalyst, Is it the N95 OR P100

    Which is more ideal for me when working with cobalt catalyst dust. I have done my fit test and know how to wear the respirator, I have shaved my beard and mustache off. Whenever, I want to carry out my work, I normally perform self test with my medium size half nose respirator to ensure that there was no leakage of air from the respirator, which was fit tested for my size, which of the respirator between the N and P will I importantly go for, thanks

    1. estaeheli
      If it a inexpensive dust mask a medical supply outlet. If you are looking for an N95 mask, I like the one with the rebreather unit attached which is sold at Amazon. Would recommend you use the link on Ken’s site so he gets credit for the sale, it does not cost you anything.
      Yes, we have used them. Dh can not breathe smoke from the wood burning stoves in our area, especially when the wood they are burning is pine or scrub oak.

  6. Comfort and ease of breathing, I am a Peds doc In CA and treated a lot of kids with TB over the years and it’s gets tough to wear, get woozy and a little agitated with an n95 on for more than a couple hours, I think you might rebreather your own exhaled CO2, but I never looked into it. I would say the fit is the most important aspect, so whatever you get, duct tape it to your face. I do see your point, but the devil is in the details

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