Written and maintained by CASRAI Editorial Board
Last updated
General product information only, not medical advice. Respirator selection and use at work falls under your employer’s respiratory protection program.
There is no single N95 size scale. Whether a size choice exists, and what it is called, depends on the manufacturer and the model. This page lists the size options for specific N95 models as printed in two manufacturers’ documents, then covers how CDC/NIOSH says to check whether a respirator fits. Check your product’s labelling and instructions for use for the options on the model you actually have.
N95 size chart by model (3M and Moldex)
Every model below is listed by its maker as an N95. Size words are the manufacturer’s own.
| Maker and model | Size options listed | Source |
|---|---|---|
| 3M Health Care Particulate Respirator and Surgical Mask 1860 / 1860S | Standard (1860) and “small” (1860S) | 3M Quick Reference Guide, Oct 2020 |
| 3M VFlex Health Care Particulate Respirator and Surgical Mask 1804 / 1804S | Standard (1804) and “small” (1804S) | 3M Quick Reference Guide, Oct 2020 |
| 3M VFlex Particulate Respirator 9105 / 9105S | Standard (9105) and “small” (9105S) | 3M Quick Reference Guide, Oct 2020 |
| 3M Aura Health Care Particulate Respirator and Surgical Mask 1870+ | One product listed, no size variant | 3M Quick Reference Guide, Oct 2020 |
| 3M 8210 | One product listed, no size variant | 3M Quick Reference Guide, Oct 2020 |
| Moldex 1500 N95 | Five sizes: Extra Small (1510), Small (1511), Medium (1512), Large (1513), Low Profile (1517) | Moldex flyer 9700-976, March 2013 |
| Moldex 3200N95 | Three sizes: Small, Medium/Large, Low Profile | Moldex flyer 9700-976, March 2013 |
| Moldex 2200N95 | Three sizes: Small, Medium/Large, Low Profile | Moldex flyer 9700-976, March 2013 |
| Moldex 2300N95 | Three sizes: Small, Medium/Large, Low Profile | Moldex flyer 9700-976, March 2013 |
| Moldex 1200N95 | Medium/Large only | Moldex flyer 9700-976, March 2013 |
The 3M guide is Release 7 (October 2020) and the Moldex flyer is dated March 2013, so both may lag the current catalogue. The table is a sample of models, not a list of every N95.
How to read the chart
- A trailing S is not a universal “small”. 3M labels 1860S, 1804S and 9105S “(small)” in its guide. The same guide lists 8110S without any size label, so the letter alone does not tell you the size.
- “Standard” is not a measurement. The 3M guide does not publish face dimensions for any of these sizes, and neither does the Moldex flyer.
- Low Profile is a Moldex style listed beside its sizes, not a step between small and large.
- Moldex describes its sizes as “color coded”, but the colours are the manufacturer’s own system, not a published standard, and the flyer does not say which colour is which size. Read the colour key on the box.
How to tell whether a size fits
CDC/NIOSH, in “How to Use Your N95 Respirator” (page reviewed March 12, 2025), says: “Gaps can also occur if your N95 respirator is too big, too small, or it was not put on correctly.” It also says: “If you cannot get a tight seal, try a different size or style.”
- “Check for gaps every time you put on your N95 respirator.”
- For a seal check: “Place your hands on the N95 respirator, covering as much of it as possible, then breathe out.”
- “If you feel air leaking from the edges of the respirator, or you are wearing glasses and they fog up, it is not snug.”
- “Jewelry, glasses, and facial hair can cause gaps between your face and the edge of the respirator.”
A seal check is done by the wearer each time a respirator is put on. It is a different thing from a fit test. In US workplaces where respirators are required, 3M’s guide states that “a written respiratory protection program must be implemented meeting all the requirements of 29 CFR 1910.134, including training, fit testing and medical evaluation,” and that 3M products in it are “occupational use only.” See respirator fit testing requirements for what changes when the size or model changes.
Equivalence notes
The manufacturer documents above use their own size names and publish no common scale, so a “medium” from one maker should not be assumed to match a “medium” or “Medium/Large” from another. KN95 and other respirator types are covered in what is an N95 respirator; this page does not give size equivalences for them.
Common mix-ups
- Assuming S, M or L means the same thing across brands.
- Reading “Low Profile” as a size between small and large.
- Treating a single-size model such as 1870+ or 8210 in the 3M guide as if it came in small and large.
- Treating a good seal check as a fit test.
FAQ
What is an N95 mask?
Moldex describes its 1500 N95 as “NIOSH certified as an N95 respirator.” N95 is a certification mark of the U.S. Department of Health and Human Services, per CDC/NIOSH. See what is an N95 respirator and NIOSH-approved N95 masks.
What is a KN95 mask, and how do I wear one?
KN95 is covered in what is an N95 respirator. Follow the manufacturer’s instructions for the specific product. This page does not list KN95 sizes.
How do I choose between N95 sizes?
Start with the options your model offers (chart above), then use the CDC/NIOSH checks: no gaps at the edges, no leaking air on exhale, and a different size or style if you cannot get a tight seal. In workplaces with a respiratory protection program, a change of size is covered in respirator fit testing requirements.
How do I put on, wear or use an N95 mask?
Follow the instructions for use printed with your model. CDC/NIOSH’s advice is to check for gaps every time you put it on and to be clean shaven, since facial hair can cause gaps. More in how to wear an N95 mask.
When should an N95 be used?
Where a respirator is required at work, use depends on the employer’s respiratory protection program under 29 CFR 1910.134. See respirator levels and face mask types.
Sources
Checked 2026-10-30.
- 3M Personal Safety Division, Quick Reference Guide, Disposable Respirators, Release 7, October 2020: https://portal.ct.gov/-/media/cfpc/files/ko/2020/fit-testing/3m-quick-reference-guide—disposable-respirators.pdf
- Moldex, “Correctional Industry Solutions” flyer 9700-976 REV B, March 2013: https://www.moldex.com/wp-content/uploads/9700-976_REV-B_3-13-correctional_flyer.pdf
- CDC/NIOSH, “How to Use Your N95 Respirator,” reviewed March 12, 2025: https://www.cdc.gov/niosh/ppe/php/n95-use/index.html
