Choosing A Respirator

Salty just asked me to pick a respirator for him. I researched to find what would suit his requirements. Rather than explain it just to him, I thought you all might like to hear about it too. Respirators protect health under a variety of circumstances.

Why respirators?

We have some surgical masks that we use when doing work that generates a lot of particulates we don’t want in our lungs. Problem is, he gets too much air around the edges of the masks, so they are not very effective for him. This is a common problem. It can be partly (but only partly) solved by buying masks that have the little aluminum strips over the nose to contour that area. That assist isn’t enough for the bearded Salty.

These cheap masks will stop some particles, but there’s leakage around the edges even with the aluminum nose strip.

Respirators are bigger and less comfortable. They are much more contoured to fit the face though. That gives them a better edge seal. To get a really good edge seal the manufacturers suggest shaving the beard. That’d take a Real emergency for Salty! But even without that, he’ll get a lot less edge flow with the respirator.

Surgical masks are also useless against vapors, and so-so against viruses. Viruses themselves are small enough to go through the masks, but the little spit droplets that usually carry the viruses among people are not. With respirators, you can get finer particulate filters, and/or absorption filters that provide some protection against organic chemicals and acids.

How is a respirator different?

Respirators have frames (usually of fairly soft plastic) that cover at least the lower part of the face. Some models have full face shields as well. The only significant air entry to the respirator is through one or more filters set into the frame. The frame is held in place by a strap harness.

This is the model we’ll probably go with. I’ve had good luck with 3M products in the past.*

Here’s a link to the one we’ll probably get, in case you’re interested. I’ve been pleased with other 3M safety equipment in the past. Full face versions tend to fog glasses. More upscale versions would up the comfort and perhaps the breathing ease, but not by much. Given how many hours we’ll likely spend in them (not many), these’ll be fine.

The frame and headset are reusable, with spare parts available. The filters are reusable too, but not indefinitely. For example, the vapor filters I was reading about needed to be replaced every forty work hours if used in an environment of petroleum fumes; or every month once exposed, whichever came first.

There are a variety of filters available. Some are for particulates only. Others have chemical absorbent properties to protect against defined levels of particular classes of compounds. For the more expensive vapor filters, a cheaper particulate filter can be used as a pre-filter. The literature didn’t specify, but previous experience tells me the point of that is to extend the useful life of the more expensive filter, which is likely to be quickly clogged if there’s lots of dust.

What filters to get for the respirator?

We are absolutely getting particulate filters. We’ll use them often enough in normal times. They make dealing with any inhalable particulates safer. That includes blocking common allergens. Hay-fever be gone!

The P100 particulate filters are also 99%+ protection from viruses. That was a big concern of mine, as it’s one of the prepping uses we foresee for this equipment. The normal product literature was not clear on this point — they’re trying to sell to painters and welders. 

Since the filters have different uses, they’re color coded. These nice pink ones are very protective.

Fortunately, as soon as I hit the academic literature I found a good answer. (1) The two common sorts of particulate respirator filters available are N95 and P100. The N95 proved about 95% efficient at stopping viruses aeresolized in the way you’d probably find them in a pandemic, say. The P100s were over 99% efficient at stopping them.

We’ll probably also also get a few filters that work against organic vapors, radionuclides, and acids. Given our rural situation, the real risks we face along this line are spills of agricultural chemicals as they’re being transported. That’s worth being prepared for — in fact, its one scenario our emergency management people in the county prep for.

Here’s a sheet with information on the filters that fit our respirator choice. We’ll get a bunch of 2071s for carpentry, allergies, and the like. We’ll keep a smaller number of 2091s for the agricultural chemical problem. Nobody bothers to nuke the hinterlands, so I’m not worried about radionuclides.

Is the respirator then the ultimate protection?

No. Self-contained breathing apparatuses are the ultimate protection. If Salty and I had to move through an area of an ammonia leak, we’d be wearing our scuba gear. Yeah, we’d look silly, especially since we’d be wearing the masks too, for eye protection. But it would work.

Firefighters and other rescue workers have smaller, more convenient versions designed for on-land use. Key features include no access of outside air to what’s being breathed and a complete airlock for the eyes as well. Of course one must bring along a tank of compressed gas to breathe from.

Well, it’s not Designed for on-land protection, but it’d sure work!

If we didn’t already have scuba gear, we’d remain without the ultimate in inhalation danger protection. That’s a lot of expense, and a little annual maintenance, for such a low-probability event, imo.

Salty’s take on masks and respirators

Salty knew what he was doing when he asked for the respirator. He wrote about the difference between masks and respirators here. I got delegated to do the choosing because making such selections was one of my professional responsibilities, once upon a time.

* We here at 3BY have no financial interest in any products mentioned.

Shameless photo sharing! Here are a few shots of Salty & Spice with regulators!