(C) Daily Kos This story was originally published by Daily Kos and is unaltered. . . . . . . . . . . Got Smoke? Wear your N-95! Fun home test shows it really works against smoke *if it is fitted well* [1] ['This Content Is Not Subject To Review Daily Kos Staff Prior To Publication.'] Date: 2023-09-27 This is about a wildly successful test of a KN-95 mask, but... let’s get the unfortunate part over with first: Mr pixxer and I have not weatherstripped our house well enough. Our climate makes air conditioning irrelevant; we do turn on the furnace in the mornings in the winter, and even run it most of the day on occasion, but this ain’t Vermont. It’s Berkeley. So, we’ve been lax. Definitely, we should put in better weatherstripping. Now the lackadaisical weatherstripping has come to haunt us. It’s smoke time, and the air quality, per Purple Air, has been in the 150s for the most part. And our failure to do first-rate weatherstripping — air conditioning and heat are not the only things, who knew? — now means The Smoke Gets Into The House. We have a Purple Air indoor air monitor — a cute little egg-shaped thing, which, when happy, has a green spot on its top, and when really peeved at us, turns that spot a bright red. Grilling on our range grill tends to anger the egg mightily. But it usually greens out pretty quickly, as soon as the cooking is done. Super-duper range hood helps a lot. Last Friday, with smoke from the northern fires being blown south to us, the Egg was registering an indoor particle count close to the outdoor particle count, in the mid 150s — ugly, but not a terrible health threat to two pretty healthy/lucky people. This is from the 20th of September, showing the saturation by Purple Air monitors in parts of the East Bay and SF. White areas have no monitors, no doubt b/c they are parkland and nobody lives there. The experiment: Mr pixxer tried an experiment: He took a much-used old KN-95 mask and put it over the underside of the egg. The egg has 3/8-inch-high, 3-inch long gaps along the bottoms of both sides, where the air comes in. Would the mask “protect” the egg from breathing/detecting small smoke particles? When Mr pixxer put the mask on the egg, the AQI reading fell from the actual 150+ “red air” to the “low yellows” — maybe 55ish. Pretty good! If the egg actually breathed, it would be a lot healthier with the mask on. The Egg — Purple Air indoor monitor — “wearing” a KN-95 mask, and detecting AQI about 55. Good cookbook it’s sitting on, btw. But that’s not a reduction to 5% of the total particles, which is what’s expected for a mask rated “95.” So Mr pixxer scoffed, “So much for 95%!” But I said (reasonably enough), “The mask is not designed to fit an egg!” Rising to this challenge, Mr pixxer added a rubber band around the bottom of the egg to seal the mask entirely over the intake areas on the lower sides. Now, the mask fit the egg perfectly. The Egg wearing a KN-95 with added elastic (around the bottom, you can see it at right) to make the mask fit perfectly. Remember how all the instructions all said to be sure your mask was “well-fitted”? The Egg’s reading of AQI dropped to *** 2 ***. That is what the egg was detecting (“breathing”?) when it was “wearing” a perfectly-fitted — though old and much-used — KN-95 mask. Color me impressed. Purple Air will show you a graph of AQI over time for any monitor. This graph shows the dramatic story of our KN-95 test, from the indoor AQI in the red zone, a rapid drop into the low yellow after the mask was applied, and then, after a few minutes, with a rubber band added to seal the mask well, another rapid drop to detecting virtually no smoke particles at all. I should have taken a movie of the egg when Mr pixxer removed the mask — it shot up almost immediately, from its green glow, back to orange, roughly the outdoor air quality by that time. You can also see this on the graph. Remember SARS? I’m not remotely an expert on particles, but here is a bit of what I’ve found about smoke and about SARS particles: The size of SARS-CoV-2 virus itself ranges from 0.07 μm to 0.09 μm (μm=micrometer=micron). So, that’s seriously small! — about 8/100,000,000ths of a meter, if I’ve got my orders of magnitude on straight. But the virus particle typically is not in the air on its own — it travels as part of an aerosol particle, or a droplet. The word “droplet” seems to be used for larger particles, which tend to succumb to gravity in a short distance, hence the early idea of “social distancing” at 6 feet. One imagines two people with a pile of droplets harmlessly on the ground between them. Nope — turned out the virus is spread more by the even tinier aerosols, which can stay airborne for hours and hours* and these aerosols are 3 microns/micrometers and smaller. But this is also the size of particle registered in the Purple Air detectors — less than 2.5 microns. So it’s not surprising that if your mask is designed to screen out stuff like SARS, it will also do well against the particles that Purple Air detects. Or other stuff (RSV, flu — get your vaccines!). *READ THIS GREAT STORY about how the original “Oh, just stand six feet apart” mistake was finally corrected. -------- Purple Air has outdoor and indoor monitors for sale. Take part in citizen science! If there’s no outdoor monitor already near you (Berkeley is saturated — see map above) and you can afford to get an outdoor sensor, go for it! Or if there are plenty of outdoor monitors around, try an indoor egg as we did. And now, there’s a super-smart outdoor-or-(not “and”) indoor monitor that detects AQI, barometric pressure, temperature, and makes coffee for you in the morning. OK, not all of those, actually. [I have no interest in this company other than as an eager citizen-scientist participant.] [END] --- [1] Url: https://www.dailykos.com/stories/2023/9/27/2194944/-Got-Smoke-Wear-your-N-95-Fun-home-test-shows-it-really-works-against-smoke-if-it-is-fitted-well Published and (C) by Daily Kos Content appears here under this condition or license: Site content may be used for any purpose without permission unless otherwise specified. via Magical.Fish Gopher News Feeds: gopher://magical.fish/1/feeds/news/dailykos/