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Contra Wirecutter on the IKEA air purifier

dynomight.net

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Re: Contra Wirecutter on the IKEA air purifier

#561

Post by tkgally »

hypersoar wrote: post #51

The Wirecutter is a highly flawed review site, but at least it's a real one. There are vanishingly few left for general consumer products. There's WC, Consumer Reports, and what else? They've seem to have all been killed off. When I'm researching some category of product, I feel lucky if I find any professional reviews written by people who have actually touched the thing they're reviewing. I know we've all had the e…

A good specialized site and YouTube channel is Garage Gym Reviews [1]. Their reviews are clear and thorough and should be useful references for people buying gym equipment for the home.

The owner can go into obsessive detail about equipment features that I, at least, have never thought about, like knurling on barbells [2]. I have learned a lot from his videos.

[1] https://www.garagegymreviews.com/

[2] https://youtu.be/5rFSsUx_KDI

Re: Contra Wirecutter on the IKEA air purifier

#562

Post by thaumasiotes »

addicted wrote: post #392

This article actually makes a bunch of claims itself that are false. For example, it claims that the Wirecutter believes air filters work like sieves. Whereas the Wirecutter review page for air purifiers goes into how they do not behave like sieves and also references a NASA study that shows how HEPA filters are good at capturing both particles smaller and larger than the 0.3 micron test standard. It’s pretty obvious…

> This article actually makes a bunch of claims itself that are false.

There's this howler:

> This passage implies that a (“true”?) HEPA filter is designed to capture particles that are 0.3 microns or larger. But an H13 filter must, by definition, capture 99.95% of particles of all sizes.

According to this guy, an H13 filter is required to capture 99.95% of neutrinos that pass through it. He's not in a position to accuse anyone of not knowing what they're talking about.

Moving to wikipedia, we see this text:

> Common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95% (ISO, European Standard) or 99.97% (ASME, U.S. DOE) of particles whose diameter is equal to 0.3 μm

I know which of those claims is more plausible. The standard described by wikipedia is theoretically capable of both being measured and being met. Neither is true of what dynomight.net says.

Re: Contra Wirecutter on the IKEA air purifier

#563

Post by Lazare »

99_00 wrote: post #47
jefftk wrote: post #41

Agreed: the Wirecutter's emphasis on HEPA is not right for a purifier that sits in a room. Once you get to reasonably high removal efficacy (even 90%, let alone 99.5% vs 99.97%) flow rate matters far more than filter spec. I also wish the Wirecutter would publish more detailed logs. They just check the particle density after half an hour, which is generally super low. Instead they could show the particle density curv…

>HEPA is not right for a purifier that sits in a room Why not? I don't know anything about HEPA, or quality, air flow, etc.

For EU standards, a filter removes X% of the hardest particle size to remove (called the Most Penetrating Particle Size or MPPS). That size varies between filters, but is often around 0.3 microns. Filters will do better than X% for particles both larger and smaller than the MPPS. So for the EU standard, we're saying "it'll do X% worst case, and better than X% for all other cases, meaning it'll always filter out more than X% of all particles, regardless of size".

If X% is 99.95% or higher and below 99.9995%, it's technically HEPA; 99.9995% and above it's ULPA, and below 99.95% (but 85% or higher) it's EPA.

So let's say you've got an E12 filter that removes 99.6% of particles. Technically not HEPA, but after one pass through the filter and you've got 0.4% of the particles left. Two passes and you've got 0.0016% left, three passes and it's 0.0000064% left.

An H13 filter might remove 99.97% of particles. One pass and you've got 0.04% left, two passes and you've got 0.000016% left.

Or in other words, one pass through a technically HEPA filter might leave you with 25 times more particles than two passes through a technically non-HEPA filter. So if the air is cirulating back through the filter (as it would in a closed room), what matters is both how good the filter is and how much air it can filter. And since at the high end the filters are all so good, the volume of air processed dominates. A filter that processes twice as much air is vastly better than one that filters out an extra fraction of a percent of particles.

(US standards are similar, but the cutoff for HEPA is 99.97% of 0.3 micron particles, not 99.95% of "whatever the filter is worst at". But the difference is generally irrelevant.)

Re: Contra Wirecutter on the IKEA air purifier

#564

Post by spatley »

idk1 wrote: post #388

Can anyone tell me what 'Contra Wirecutter' means. It's like I've gone mad, everyone seems to know what this term means, both of these words mean nothing to me and I've spoken English my entire life. You're all acting like they're two words that make perfect sense. Haha. It would be really great is someone could explain the two words to me.

Contra wirecutter is clearly invented for this article. But in short I take it to mean that it asserts a point of view that is in disagreement with the point of view asserted on the popular wirecutter.com product review site.

Re: Contra Wirecutter on the IKEA air purifier

#565

Post by thaumasiotes »

Lazare wrote: post #557
addicted wrote: post #392

This article actually makes a bunch of claims itself that are false. For example, it claims that the Wirecutter believes air filters work like sieves. Whereas the Wirecutter review page for air purifiers goes into how they do not behave like sieves and also references a NASA study that shows how HEPA filters are good at capturing both particles smaller and larger than the 0.3 micron test standard. It’s pretty obvious…

The Wirecutter article is pretty bad though: > But it isn’t a true-HEPA purifier, or a very powerful purifier, period. It’s designed to capture PM2.5—that is, particles 2.5 microns in diameter and above, in contrast to the 0.3-micron HEPA standard. That means it’s optimized for larger airborne particles such as pollen and mold spores, rather than for very fine particulates like wildfire smoke, as HEPA filters are. Fi…

> Second, and a minor point, the 0.3-micron standard related to the US HEPA standard, not the EU one. It is true that acording to IKEA it doesn't meet the EU standard for HEPA (barely), but we don't know whether it meets the US one.

Wikipedia cites this statement:

> Common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95% (ISO, European Standard) [...] of particles whose diameter is equal to 0.3 μm

to "European Standard EN 1822-1:2009, "High efficiency air filters (EPA, HEPA and ULPA)", 2009". Have they made a mistake? ( https://en.wikipedia.org/wiki/HEPA )

The same sentence goes on to note that the American standard is similar, but more strict, requiring filtration of 99.97% of 0.3 μm particles. As such, it is not possible to meet the American standard while failing to meet the European standard, so there's no need to discuss the American standard separately.

Re: Contra Wirecutter on the IKEA air purifier

#566

Post by modriano »

bradlys wrote: post #484
fartcannon wrote: post #465

Earlier quoted context omitted.

If you're pro-something, surly you'd want people to do it?

I’m pro-choice - does this mean that I think every fetus should be aborted?

Pro-choice != pro-abortion.

Pro-choice means every pregnant woman should have the choice and a real chance to abort their pregnancy if they choose. It's kind of right there in the name.

Re: Contra Wirecutter on the IKEA air purifier

#567

Post by harrisonjackson »

hackernewds wrote: post #182
bombcar wrote: post #154

Earlier quoted context omitted.

Some might say this is intentional, the whole point for the link is to corrupt your Amazon cookie so that they get credit for the (next?) purchase you make. At least that's how I've always assumed the links work, not that you have to buy the exact product immediately.

This blew my mind. And would be highly unethical that Amazon should know, since the accounting often happens on the publisher's side

The product link not resolving doesn't improve this payout for the publisher. The cookie gets dropped _either way_ and when a purchase happen Amazon will check for a referral cookie and payout accordingly for whatever qualifies in that cart.

As long as you end up on amazon's site, then the cookie was likely dropped and your next purchase may pay out affiliate commission to whichever publisher's links you most recently clicked through.

Re: Contra Wirecutter on the IKEA air purifier

#568

Post by harrisonjackson »

logifail wrote: post #559

I'm pretty skeptical (and that's putting it mildly) of any website that uses affiliate marketing links. I can't see how objectivity can survive in that environment. A concrete example is frequent flyer/travel blogs. I vaguely know the guy who runs the UK's largest one, I've met him in person several times, fairly nice bloke. He's worked very hard to build his site, publishes high-quality content, and is often the fir…

There are categories where the incentives are equal enough across all the products so you can maybe possibly trust the reviews more.

If all the products are similarly priced and from the same retailer (ie amazon) then there isn't any incentive to recommend anything other than the best.

Re: Contra Wirecutter on the IKEA air purifier

#569

Post by Lazare »

thaumasiotes wrote: post #565
Lazare wrote: post #557

Earlier quoted context omitted.

The Wirecutter article is pretty bad though: > But it isn’t a true-HEPA purifier, or a very powerful purifier, period. It’s designed to capture PM2.5—that is, particles 2.5 microns in diameter and above, in contrast to the 0.3-micron HEPA standard. That means it’s optimized for larger airborne particles such as pollen and mold spores, rather than for very fine particulates like wildfire smoke, as HEPA filters are. Fi…

> Second, and a minor point, the 0.3-micron standard related to the US HEPA standard, not the EU one. It is true that acording to IKEA it doesn't meet the EU standard for HEPA (barely), but we don't know whether it meets the US one. Wikipedia cites this statement: > Common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95% (ISO, European Standard) [...] of particles…

From the same Wikipedia page:

> The specification used in the European Union: European Standard EN 1822-1:2009, from which ISO 29463 is derived,[4] defines several classes of filters by their retention at the given most penetrating particle size (MPPS): Efficient Particulate Air filters (EPA), HEPA and Ultra Low Particulate Air filters (ULPA).

The Wikipedia citation goes to a specification which is, annoyingly, not freely available, but Google seems to confirm that Wikipedia is correct. Many sources confirm that EU standards measure penetration at the MPPS, I can find nothing suggesting they use 0.3 microns for anything.

I think the introduction paragraph for that Wikipedia page is simply wrong, and it's conflating two different standards. The actual section on HEPA specifications, however, is much clearer.

Re: Contra Wirecutter on the IKEA air purifier

#570

Post by branko_d »

kitsunesoba wrote: post #82
mrkwse wrote: post #70

Earlier quoted context omitted.

It will be interesting if LMG can pull off what Linus is aiming for with the massive investment in a laboratory environment. There are huge parts of the tech market where the most critical reviewing you can find is anecdotal accounts of if the reviewer liked a product or not (or the more clinical reviews are drowned out by the anecdotal noise).

I'm hopeful for LMG's lab too. It's still a bit of a gamble, but from the sound of it the company is set up such that they can review products in an objective, data-backed way and tank any blowback from manufacturers that occurs as a result. It's much more focused on enthusiast computer hardware, but Gamers Nexus[0] is doing good things in this space too. Their style is much more dry and data-dense than LMG's though,…

I think rtings.com are doing a good job on monitors.
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