Originally Posted by markopolo
I went down the water filter rabbit hole last year
I don't think you can confirm micron rating with NSF. I did spend a fair bit of time searching through the listings on their site and exchanged emails with NSF about one particular 3M 0.5 micron product that met NSF 401 according to their site but no claims of meeting NSF 401 in any 3M literature or website. They said they'd pass the info on to an account manager and suggested I bring it to 3M’s attention ....... I thought that would be their job.
My understanding of the 0.2 micron rating of the 3MFF101 cartridge is that it is nominal and not absolute. That mean particles/items larger than 0.2 micron can slip though depending on particle/item shape. Something .03 micron long x .01 micron wide might get through.
In the end, I decided to go with 0.2 micron nominal over 0.5 micron thinking that it's likely just a bit better.
Here's link to the Everpure 2FC EV9691-56 cartridge data sheet: https://www.pentair.com/content/dam/...Spec-Sheet.pdf
Also page 8 here: https://www.pentair.com/content/dam/...%20Catalog.pdf
Note: no lead reduction claimed.
Here's the link to NSF drinking water search index: Listing Category Search Page | NSF International
I had found those same documents, after a bunch of looking as they don't make it particularly easy if you don't know the actual part numbers for sure.
The no lead is a bummer and to get a Everpure that takes out lead to just below recommended make you have to get one with scale removal and give up their "bacterostatic" control. You also are two inches longer and go to .5gpm from 1.5gpm so not going to work for our spot unfortunately, and we do the whole van water system, not just the sink so .5 gpm is too low for us.
Here is what the contact at Everypure sent to me about the filter micron rating and cyst removal
EV969156 2FC filter with the EV925924 QL3B Head will provide up to 1.5 GPM flow rate, 6,000 gallon filter capacity, 0.2 microns tested by Pentair and 0.5 micron tested by NSF also these set up should need Space required: 5 x 5 x 14 in. (13 x 13 x 35.56 cm) including 2Ĺ inches of clear space under unit for cartridge change. Bypass Plug part number is the EV310876.
Spec. sheet attached.
2FC filter is Validated by ISO 17025 accredited lab for 99.999% reduction of Pseudomonas diminuta following the ASTM F838-05 protocol for the validation of 0.2 μm sterilizing grade filters.
I had read somewhere else, which I think was a forum type post so didn't mention it, as unconfirmed in my mind, that the difference in the .2 to .5 is something like the difference between 99.9% and 99.99% or the .2 micron trapping to get NSF which gets very restrictive and expensive I would assume. I wasn't able to find an actual confirmation of any of that though in a quick search.
As you said, rabbit hole, and lots of them all over the place in trying to get any real and comparable data on any of this stuff. Even if looking at the specs for NSF it is weird because they talk about meeting the spec for "some" of the contaminants.
Some of the new 3M cartridges seem to be less expensive than the older version where, compared to the market, but with suggested prices and actual being so far apart on everything, it is had to tell. They have moved away from the .2 micron rating on an awful lot of their products, though, like the small filter cartridges of similar size to our old US-B1.
I do worry a bit about the Everpure ratings also due to the very high gallons of life they tout in such a small cartridge, plus the higher flow compared to other brands. Getting 1.5gpm and 6K gallons life is definitely different than you normally see.