(This post was inspired in part by this comment by Florin, which I think makes some good related points.)

Elastomeric respirators are reusable respirators made with some elastic material such as silicone, typically with N95 or better filters attached. They are low cost (there's currently one from a reputable manufacturer on sale for $2.99[1], which may be a loss leader but even the regular price is just $10.99) and are easier to correctly use than disposable N95s (since they form a soft seal against the face and are therefore less prone to leaks), and of course are much more effective than the cloth or surgical masks that most people still wear, even now (if they wear masks at all, e.g. in Chengdu, China).

Image

It seems easy to imagine that if everyone or most people wore such a respirator, COVID would be much easier to control and we could depend less on other measures, including draconian, extremely high cost ones like lockdowns. Yet every locality on Earth throughout the pandemic, including present day China, would apparently prefer to not mandate or even encourage using such respirators and instead incur the high costs of other control measures. I'm tempted to pass this off as typical irrationality of humans, but feel like I should check with the LW hivemind before I do. Is there some reasonable explanation that I'm missing?

(At one point I saw A Clunky Mask May Be the Answer to Airborne Disease and N95 Waste in the NY Times, which made my heart jump a little, but it was only talking about use of these respirators by medical personnel, not the general population.)

ETA: Elastomeric respirators do have some downsides, however many of them can be mitigated through better design. Here is an improved design which is currently on sale for $89.99, but can probably be made much cheaper if manufactured at scale.


  1. The site has a $7.95 shipping fee. It also has a disposable N95 mask (which I've used and recommend) on sale for $0.19 each in quantities of 50. ↩︎

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I‘ve been in China from the very beginning of the Pandemic, and possibly will continue for at least one year. And for some very "prepper" accident, I personally purchased a 3M HF-52, in Dec. 2019, right before the lockdown took place.

And with quite a reasonable check frequency of the availability of the mask & replaceable filter, I can personally confirm that (at least industrial) filters have NEVER been out of stock even during Jan./Feb. 2020. A simple fact is that despite the public can retrieve knowledge from the internet that it's almost equivalent, few choose to purchase it.

In an Asian country like China where physical appearance matters most when going out to adolescents, the feeling of "standing out" might be a disaster.

When discussing it in the rationalist community, we would seldom discuss whether appearance matters in front of life risk, but this might still stand for the general public.

I can think of many reasons why elastomeric respirators haven't been widely used.

  • Slow expert opinion change: airborne transmission is not significant/only cause of infection
  • Bad assumptions: variants won't become significantly more contagious 
  • Unfamiliarity with elastomeric respirators: no/few studies, seem too uncomfortable, some advantages aren't obvious (e.g., better face seal and comfort)
  • Naive empiricism: China's lockdowns "worked," and other Asian countries (like Hong Kong, South Korea, Taiwan, and Japan) controlled covid well without respirators
  • Hope: a combination of cloth/surgical masks and vaccines is good enough (see "Naive empiricism")
  • Traditional expert training: contact tracing, vaccines, quarantine, social distancing
  • Low death rate: there's less pressure to use the most effective means of dealing with the pandemic
  • Complacency: most people that would die of covid have already died

I suspect that the main reason was that most experts thought that a combination of traditional masks, contact tracing, vaccines, quarantine, and social distancing would be good enough. Old school epidemiology and naive empiricism strongly suggested this: China's lockdowns "worked," and other Asian countries (like Hong Kong, South Korea, Taiwan, and Japan) controlled covid well with masks, contact tracing, and border restrictions but without respirators, hard lockdowns, or even vaccines.

However, in the rest of the world, these solutions weren't practical (due to the rise of more contagious variants) or available (vaccines).

Thanks, lots of good insights in your comment. Reading it, two potential interventions come to my mind:

  1. Figure out reasons for expert/institutional inertia (why didn't they change their minds quickly once they saw evidence of airborne transmission, or more contagious variants, or traditional measures not working well enough) and try to change that.
  2. Do studies on elastomeric respirators and try to make them part of future editions of epidemiology textbooks, so they become part of the default toolkit that experts reach for.
7Florin1y
It's mostly too late for intervention #1. Now, everyone knows about these issues. However, it may do some good to replace a lot of old experts with much better ones like Zeynep Tufekci. Tufekci wasn't perfect (never mentioned elastomerics), but she quickly got a lot of things right (even took lab leak seriously) and for the right reasons. Intervention #2 has more merit, but I fear that the lack of urgency will take over and it will take too long to deploy elastomerics and/or PAPRs (which have certain advantages over elastomerics) at scale. This is starting to happen; I've seen a lot of talk about designing better respirators but nothing about deploying (or even recommending) the current generation of elastomerics to adults. The perfect is starting to become the enemy of the good. If the current crop of experts can't be reasoned with in a timely manner, one potential solution is to set-up an independent pandemic risk reduction organization. This org would make recommendations (e.g., elastomerics should replace other PPE, cheap PAPRs should be developed to replace elastomerics), take action (e.g., quick studies, cheap PAPR development and distribution), and be advised by experts like Tufekci. A possible source of funding might be the EA community.

Here's another reason I forgot to mention:

  • Expert anti-valve bias: most elastomerics have exhalation valves

And to be clear, I don't think any of these reasons are enough (although, this somewhat depends on when in the pandemic these reasons were used) to justify not recommending the use of elastomerics.

  1. For the record, anyone buying an elatomeric mask should get at least a P100, not anything with a "95" on it. A lot of people made that mistake. The one you suggested seems even better.
  2. There are better people than me to ask about this, such as Steph Guerra. However, it's possible that, in the US, N95 masks were treated like a valuable commodity early in the pandemic and the USG bent over backwards to prevent average people from buying and hoarding them. I doubt that there were 200 billion KN95 masks in China at any point in 2020 but I might be wrong about that.
  3. At some point, by summer 2022 in the US, emphasis shifted so that PPE was considered second priority to vaccination. That's where the US national security community seems to be right now, but Steph would be a much better person to ask about this, and all sorts of things related to PPE.
  4. In between, there is a third thing I know of, related to contact tracing systems in China. I'm not willing to share info about this kind of thing on a public forum, but if you're interested you can DM me with more info about you, and once I have a better idea of who you are and why you might be interested, then I'd be happy to share.

The one you suggested seems even better.


It might be a better alternative to surgical masks for children, but it's not necessarily better for adults. First, it's not independently certified (by NIOSH, for instance). And second, it lacks an exhaust valve which could make it significantly less comfortable to use for extended periods of time due to increased humidity.

A better alternative for adults is the 3M 6000 series with the optional 3M 604 exhalation valve filter, if you care about filtering the valve's exhaust.

N95 masks

KN95 masks

These aren't elastomeric respirators.

I used a P100 elastomeric respirator pretty much any time I left the house, for multiple months in 2020 during early COVID, and intermittently after that.

The main downside, for me personally, was that people generally found understanding my speech through it difficult or impossible. This was a big enough problem that I haven't used one in quite some time.

Requiring more efficient masks includes admitting that the previous mask mandate was suboptimal.

It turns those people, who virtuously wear a surgical mask into people who unvirtuously do not wear the required masking.

Most fads, including moral ones, readily admit that previous versions were suboptimal. If anything, the more rapidly changing the style, the more virtuous the ones who can keep up look.

(FWIW, I do think better masks would have provided more protection for less suffering than other preventative measures. In the absence of state-mandated good masks, I wish the social pressure had been there to make good masks trendy.)

2ChristianKl1y
The lack of social pressure for better masks and the lack of government mandates for stronger makes are two different topics. Most moral fads work in a decentral way where an individual who has an idea of how to signal a value in a stronger way can start the trend. A moral trend about the virtues of following government edicts is more centralized which less room to grow organically. 

My best guess is that Xi feels that adding a P100 mandate would be too much for the Chinese people to bear, while providing little marginal benefit on top of existing measures. It would only be worthwhile if it meant a substantial reduction in movement restrictions, testing mandates, and the amount of time people spent in quarantine and that cities spent locked down.

Xi has a policy that's working to achieve his stated aims now. The benefit of switching to a P100-based approach is hypothetical.

Plausibly, he could order a P100-based experiment in a few smaller Chinese cities. It would be really hard to know if it was working, since China currently isn't getting that much COVID. If a city switches to P100s and doesn't get COVID outbreaks, is that because the P100s work just as well, or because they're benefitting from the testing-and-lockdowns regime in the rest of the country?

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I've been wearing a 3M industrial workman's elastomeric P100 respirator (which has an exhalation vent, to which I later added a plastic fitting I found on Etsy to hold a disk of N95 mask material over that as an exhalation filter) when indoors in public almost all the time ever since COVID started: I had one in my tool collection then, and have replaced it and the filters every 6–9 months or so (which has never been difficult to do). It muffles my voice slightly, so I have to speak loudly and clearly, and I get some funny looks and occasional "witty remarks" about it, but no-one has actually been hostile. It's also uncomfortable to wear for more than around 1 1/2 hours continuously., so when working in the office or on long flights I wear a well-fitting cloth mask with approved N95 inserts (or actually the EU equivalent). But the elastomeric mask flattens my beard so that it gets a good seal, and (along with staying current on our vaccinations, and during COVID spikes staying home apart from kerbside pickups and medical appointments) has so far kept me and my mildly-immunocompromised wife COVID free, as far as we know.

No, I don't understand why everyone didn't do this. Properly worn, a P100 blocks more than an N95 which blocks more than a surgical mask which block more than cotton, all of which block more than anything that isn't worn properly. It's also cost effective, since the filters and mask last a long time. Our goal during the pandemic has been to try to reduced our estimated COVID risk down to around the level of other risks that we take on a regular basis, and for me, with a beard and a partially-immunocompromized wife, an N95 didn't do that. I could of course have shaved my beard off (and at one point did), but this way I didn't have to.

Surgical masks and N95 masks are not the same thing.

[+][comment deleted]1y20