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Comment by don-bright | Hacker News Reader

I support more research but anecdotally HEPA air filters changed my life. I used to get pretty bad respiratory infections every winter but after getting these that went away. I’m talking the simple kind with basic charcoal prefilter and fiber HEPA filter which are about $150 at most home stores or big box stores. Never used any ionization or ozone. The interesting bit is the newer ones even measure air particulates and have a variable speed option where they will speed up when they detect high pollution… Which turns out is mostly from me cooking.

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Your HEPA filters must be real ones. HEPA is just an acronym anyone can slap on anything, there's no accreditation.

Recent testing on the Vacuum Wars channel showed big differences between filters from the vacuum manufacturer and off-brand "HEPA" filters. Probably the same applies everywhere.

https://www.youtube.com/watch?v=eAIYRykQkMk

> HEPA is just an acronym anyone can slap on anything, there's no accreditation.

There are standards:

> Filters meeting the HEPA standard must satisfy certain levels of efficiency. Common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95% (ISO, European Standard)[4][5] or 99.97% (ASME, U.S. DOE)[6][7] of particles whose diameter is equal to 0.3 μm, with the filtration efficiency increasing for particle diameters both less than and greater than 0.3 μm.[8]

* https://en.wikipedia.org/wiki/HEPA

* https://en.wikipedia.org/wiki/HEPA#Specifications

Here in India you can usually tell them apart by whether they are advertised as HEPA vs "HEPA-type".

  >Your HEPA filters must be real ones.

"You need HEPA" is just marketing. What you really need is CADR (Clean Air Delivery Rate) and third-party testing.

HEPA H13 only means the filter was tested to 99.97% particle efficiency at the most difficult particle size. There's nothing magical about this number. In reality air filters can often clean better with an E11 or E12 filter (tested to 95% and 99.5% respectively), because these filters allow much greater airflow from the same fan.[0]

Remember, the clean air is immediately mixing with the dirty room air. If you get twice the airflow while "only" letting 5% of particles through, that's a good tradeoff.

CADR (tested by AHAM, not just the manufacturer's claim!) is what really matters, not HEPA vs non-HEPA.

[0] https://x.com/Engineer_Wong/status/1899144721710408038

I think the next big thing is going to be fixing cooking air pollution. Now that smoking has been in freefall it's becoming increasingly clear that cooking is the next big issue for lung cancers. Especially anything smoky or on a gas stove. It wouldn't be terribly impractical to put a much higher power extraction fan and some side walls to create a kind of fume hood like you'd get in a lab.

The EPA estimates that radon[1] is the second leading cause of lung cancer after smoking. I have a RadonEye monitor in the basement. They aren't that expensive and it's nice to have the piece of mind.

[1] https://www.epa.gov/radon/health-risk-radon

What lead you to trust RadonEye?

I wonder how one could validate a radon detector. Can one buy a phial known air/radon concentration online without ending up on some spooky list?

Naturally, you would have to account what changes in the sample during shipping, due to the short half-life...

> how one could validate a radon detector

Get a professional measurement and compare. This Reddit thread gave me pause [1].

[1] https://www.reddit.com/r/radon/comments/ptz8tt/professional_...

A radon sensor is just an alpha radiation detector. There's little reason to distrust companies making them. You don't even really need very good calibration, you just want to know if radon levels exceed some "you should take action" treshold. Real-time radon detection is really a bit overkill.

Years ago I lived in an apartment where the vent hood above the range was an overpowered commercial unit instead of the usual home stuff. It genuinely surprised me how much of a difference it made compared to 'normal' vent hoods. Higher extraction volumes, even without side walls, makes a big difference.

For around 2k it is possible to install a vent hood with the fan outside the building so it is completely silent, and has way more air flow than anything that fits above the range.

Complete silence, performance beyond anything people are used to at home. Most people don't even know the choice exists, and even if you go to a bougie specialty cooking store they'll try to dissuade you from this and instead sell you on a higher priced product that doesn't work as well.

What's annoying with both air cleaners and vent hoods, is that it seems some sellers have figured out that they want them to make noise, so people hear they are working. It's possible to make both much more quiet than they typically are.

One of the first upgrades I made to my house was buying a nice (interior) vent hood. The exterior ones need to be at least a few feet away from the stove, and my stove is right up against the wall it vents out of. I still was able to find an interior one that has 1/2 the noise and twice the airflow of the standard builder grade vent hood.

One annoyance is that almost none of the vent hood stick out far enough, ideally you want the vent hood to stick out a few inches (at least) past the front of the cook top, but almost none of them do that (likely due to head bumping issues, understandable) so a lot of effluent still escapes.

Higher extraction volumes also make heating and cooling bills go up.

It's one of those ideas that works fine when it's just a rare thing, but if 100% of households had one I guarantee we'd see headlines like "Wasteful Exhaust Vents Burn As Much Energy As Cleveland" etc etc.

I for one welcome our fume hood inspired overlords. The nice thing about fume hoods is that they're optimized for maximum extraction efficiency for a minimum extraction volume.

Everyone notices the side walls, but an overlooked secret of fume hoods is that they extract air backwards toward the back wall, not just upward.

Any air extraction pulls conditioned air out of the house - kitchen hoods, dryers, bath fans, etc. Only kitchen hoods exhaust a significant amount of air - the solution is a makeup air system.

That doesn't change anything I wrote.

Makeup air just ensures the exhaust meets its rated flow rate. It doesn't reduce heating or cooling costs (if anything it increases them).

For those interested the cheap option is box fan, something like this or duct tape https://a.co/d/3BEXNGp and a hepa filter. Works great and costs about 50 bucks.

Well you will need a particulate detector to determine the problem and then that will inform your solution.

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