Whether you’re a DIYer or a professional renovator you need to protect your lungs from the assorted stuff floating around the air as you work and picking the right dust mask is extremely important. Some of these airborne meanies are nothing more than an annoyance and some of them can kill you or shorten your life dramatically.
Do you know how to understand the ratings of dust masks and what they protect you from? There are a ton of different dust masks and respirators, so finding the right one for what you need is imperative. This post will walk you through the different levels of dust mask protection and help you pick the right one for your situation. Remember, dust masks only work to protect you if worn correctly. Having a beard, improper fit, wrong size, wrong rating, or other issues can really compromise the effectiveness of the mask and your safety so make sure you are not just finding the right mask, but wearing it properly as well.
This is only meant to serve as a quick guide and is not comprehensive. If you have questions definitely refer to the manufacturer’s ratings and descriptions.
How Masks Are Rated
Do you need a simple dust mask, a half mask respirator, a washable mask, what about those cool vents, P100 or N100, Is N95 enough protection, what does an “organic vapor” cartridge protect you from? So many questions and so few clear answers. Let’s simplify all this!
What’s the deal with all the letters and numbers? P95? N100? OV? Let’s start with the basics when it comes to picking the right dust mask. Here’s what they mean.
P, R, or N?
- “N” = not resistant to oil
- “R” = somewhat resistant to oil
- “P” = strongly resistant to oil
- “OV” = Organic Vapors
You won’t find a lot of “R” rated masks (most are “N” or “P”) but really why would you need one? Here’s my take on how to decide on the proper letter: If you’re working with oils like spraying oil-based paints or aerosols then get a “P” rated mask to protect yourself. If you are working with mostly dry particulates without any airborne oils then choose an “N” rated mask because it will be slightly cheaper most times.
95 or 100 Rating?
The 95 means it filters out 95% of particles 0.3 μm (that’s micrograms) or larger which is roughly the size of a single virus. The 95 rating is sufficient for most no hazardous materials where the only concern is the nuisance that the dust or smoke creates.
For me, it never made much sense why we would want a mask that lets 5% of airborne gunk get through when we could invent a mask that blocks 100%, but it really comes down to cost. Masks with a 100-rating are considerably more expensive than the 95% versions that look almost identical.
When to Use 95: These masks are probably well suited for woodworking and carpentry as well as medical workers looking to keep out basic airborne pathogens like bacteria and viruses. N95 masks are also helpful to protect against wildfire smoke.
When to Use 100: When dealing with dangerous particulates this is the only rating you should be using. Worn correctly a mask with a 100 rating will protect you from lead paint, asbestos, and water-based paint spraying. If there is a particulate base hazard this is the mask you need.
OV (Organic Vapor)
This is a rating that can be added to any of the above masks like a P95/OV or a P100/OV and it essentially is a mask filter with granulated charcoal inside it to protect you from solvents. If you are working around strong oil-based solvents like acetone, mineral spirits, xylene, turpentine, or others this filter will not only trap the associated particulates necessary, but it will stop the strong organic vapors from giving you a headache or worse.
When to Use OV: When spraying or brushing oil-based paints, lacquers, or stains, working with chemical strippers, or any other product that creates fumes an organic vapor rating will keep you safe.
Types of Dust Masks
Enough of the rating talk, let’s get down to picking out the right mask for you and your situation. Here’s the types of masks you’ll most often encounter and when to use them.
Nuisance Mask
Your basic run of the mill dust mask. This very light, very cheap mask is mostly to help people with sensitivities to household dust or maybe grass clippings. They are not NIOSH (National Institute for Occupational Safety and Health) rated and provide little if any protection. If you’re dealing with dangerous chemicals and vapors or dangerous particulates like lead paint or asbestos DO NOT USE THIS MASK. If you’re cleaning out a dusty attic or mowing the lawn and you want to avoid a sneezing fit then this will probably do just fine.
Disposable N95
Great all around protection from everything other than hazardous materials like lead paint, asbestos, or mold. Whatever you are doing from woodworking to cleaning this mask will provide ample protection at a minimum price. These are pretty inexpensive and lightweight so a hot sweaty face is never a problem, but do pay a little extra for the cool vent which makes it even more comfortable. When it gets dirty you just toss it and buy a new one.
Washable N95-99
These have become pretty popular with woodworkers lately probablfy because they’re pretty cool looking and if you’re a YouTube sensation then you want the camera to love you, right? I like the fact that you can wash and reuse these so they are a greener option. Makers like RZ Mask have different colors and styles to meet your needs. These are currently not available in anything that will protect you from 100% of particulates so steer clear of these dust masks if you are working with hazardous materials. Some of them have charcoal filters to protect agains fumes which is helpful as well.
Disposable N100
Just like the disposable N or P100 above these are great for ultimate protection in temporary use. If you’re not doing everyday work around lead paint or other hazardous materials this is the mask for you. Get the work done safely and then get rid of the mask for a minimal cost compared to reusable versions. This is not acceptable for OV protection, but rather particulates only.
Half Mask Respirator
These extremely useful respirators can be used and reused for a long time and their benefits are plentiful. You can swap out cartridges so you can use the same mask with P100 cartridges when scraping lead paint and then switch to an OV cartridge when you go to spray some paint. Unlike the disposable masks you can now have OV protection when you need it. That flexibility is huge and you pay for it at about four times the cost of the disposable masks. Be sure to keep these masks clean by wiping the insides down with alcohol because they can develop mold inside them from repeated sweaty use if you don’t stick to a stringent cleaning process. It’s worth it to get the vented ones for a much cooler and more comfortable experience.
I hope that helps you make the right decision for which dust mask will meet your needs. Let me know in the comments below if you have other suggestions or styles that you like.
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I love old houses, working with my hands, and teaching others the excitment of doing it yourself! Everything is teachable if you only give it the chance.
You mentioned the “N95 masks are also helpful to protect against wildfire smoke”. That might be true but depending on what is burning in that wildfire some wood will release formaldehyde in the smoke, which N95 can’t filter out.
I sold safety equipment for a living many years ago and have studied workplace health and safety since then. You need to amend your statement or remove it from the article. There are many studies in many countries that show formaldehyde vapour in bushfire/wildfire smoke.
N95 is not suitable for these situations. They are better than nothing but that’s not exactly reassuring.
Good information always wondered which mask to choose, apparently, I’ve inhaled (accidentally) lead dust and few other horrible damaging dust particles..
The good thing about lead is that it will slowly be flushed from your body unless you have constant exposure.
You merely included a few words on beards, yet provided zero info about masks for them. While a full beard does pose problems with OV masks, many of the particulate ones work quite well with them as the longer facial hair when compressed acts as it’s own filter.
I once worked in a concrete manufacturing facility where the dust from sand, lime and Portland cement were extreme and an everyday occurrence. Quarterly testing was done to ensure compliance with respiratory filters. The N95 type worked very well with facial hair.
Ken, according to most manufacturers any facial hair negatively affects the mask and is not recommended. We use full head contained systems for people that have masks because that is the only truly safe method I have found.
Great info Scott! Do you happen to know a general rule of thumb on when to replace the cartridges for the half mask style respirators?
I change them fairly preemptively after about 100 hrs of use.