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Muncie4 t1_j9jf4fs wrote

Most things in life a comparison metric we can rely on. On a near equal footing, if you wanted an air filter, we have metrics for those so one might compare functionality. HEPA is the gold standard and its also known as PM 2.5. Want something better? There are PM 1 filters which remove even more from the air. And I'm sure there's something in-between or maybe even better than PM 1.

There is nothing like the above with water filters. There is no standard. You can buy a water filter at Dollar General, one from Brita at Walmart or an under sink system from your cousin Terry who is hawking the latest Multi Level Marketing water purifier and you have no way of knowing which is doing a better job. Why? There's no rating system like air cleaners. Air cleaners are rated on Particulate Matter (PM) containment. Water cleaners are based on nothing.

Now here is where, again, I'm going to say: If what I have said is wrong, please someone prove me wrong. I'm hoping someone comes off the top rope and puts me in my place with a knowledge drop.

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aggressive_seal t1_j9jyq9b wrote

Has no one (I'm thinking Consumer Reports or something like that) done a independent study comparing different filters? Do the better quality filters not publish any data to demonstrate their effectiveness? I gotta get into the water purifier business.

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sponge_welder t1_j9ly6sh wrote

The industry standard tests are ANSI standards 42, 53, and 401. 42 addresses contaminants that aren't health related (chlorine, particulates, etc), 53 addresses contaminants that affect health (lead, VOCs, asbestos, etc), and 401 addresses "emerging compounds" which are things like prescription drugs, pesticides, and other incidental things whose effects are still being discovered.

Most good filters will be certified for several of the more common contaminants from these standards, Brita Elite and Longlast+ filters are certified for 13 of the contaminants in Standard 53. You can find this on Brita's performance data sheet, and Pur has similar info available

The difficulty is because there are so many different contaminants that testing and certification becomes really expensive and convoluted. Just because a filter has an NSF certification doesn't mean that it's certified to filter the specific contaminant you're looking for.

Then you get into sketchy stuff like Berkey and other rando filters where getting certified for all the containments they claim would cost over a million dollars, so there isn't really a way to verify their performance figures except running an independent test for hundreds of chemicals.

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Muncie4 t1_j9kk6yb wrote

I haven't seen any data is the problem. I hope someone has data that we consumers can use.

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