A PFAS water filter needs two separate things checked, not one: WaterMark certification if it connects to your plumbing, and NSF/ANSI 53 certification carrying a PFOA/PFOS reduction claim to prove it actually removes PFAS. A filter can hold either one without the other, and most buying guides do not explain the difference.
What actually counts as a "certified" PFAS water filter?
There is no single "PFAS certified" badge. A genuinely certified PFAS filter carries an NSF/ANSI 53 listing that specifically includes a PFOA/PFOS reduction claim, tested by an accredited lab against real contaminated water. WaterMark, NSF/ANSI 42 and general "NSF approved" language do not prove PFAS removal on their own.
"NSF certified" gets used as one phrase when NSF actually issues certifications against dozens of separate standards, each testing something different. A filter certified to NSF/ANSI 42 has been checked for chlorine taste and odour reduction, and that says nothing about PFAS. A filter certified to NSF/ANSI 58 has been checked as a reverse osmosis system, and depending on the specific listing that may or may not include a PFAS claim. Only a listing that names NSF/ANSI 53 with a PFOA or PFOS reduction claim actually proves the filter removes PFAS.
WaterMark and NSF test completely different things
WaterMark certification, under AS/NZS 3497, is mandatory in Australia for any water filter permanently connected to household plumbing. It confirms the unit will not leak, will not fail under pressure, and will not leach anything harmful into your water. A licensed plumber is not permitted to install a plumbed-in filter without it.
What WaterMark does not do is test whether the filter removes any specific contaminant. NSF certification works the other way around: it is voluntary in Australia, but it is the only one of the two that tests actual contaminant removal.
| Certification | Administered by | Legal status in Australia | What it actually proves |
|---|---|---|---|
| WaterMark (AS/NZS 3497) | Australian Building Codes Board | Mandatory for plumbed-in filters | Structural safety, pressure rating, no leaching |
| NSF/ANSI 53 (PFOA/PFOS claim) | NSF International | Voluntary | Specific PFAS reduction under tested conditions |
| NSF/ANSI 42 | NSF International | Voluntary | Chlorine taste and odour reduction only |
| NSF/ANSI 58 | NSF International | Voluntary | Reverse osmosis system performance |
A filter can legally be installed in an Australian home with WaterMark alone and no NSF certification at all. The two certifications are also policed differently: WaterMark relies on periodic factory audits, while NSF conducts unannounced factory audits and requires certified products to be retested periodically to keep their listing.
Which NSF standard actually covers PFAS (and why you'll still see "P473" mentioned)
You have probably seen NSF/ANSI P473 mentioned alongside NSF/ANSI 53, as if they were two separate current standards to choose between. They are not. P473 was NSF's original standalone protocol for PFOA and PFOS reduction claims. In 2019, NSF folded P473 into NSF/ANSI 53 as a specific reduction claim within that broader standard, rather than continuing to issue it separately. A filter marketed today as "P473 certified" is, in practice, describing an NSF/ANSI 53 listing that carries the PFOA/PFOS reduction claim.
Practically, this means one thing when checking a filter yourself: look for NSF/ANSI 53 with an explicit PFOA/PFOS reduction claim, whether the listing calls it "53" or still uses the older "P473" language.
There is one more standard worth knowing if you are buying an under-sink or plumbed-in system with brass fittings: NSF/ANSI/CAN 372, which verifies low-lead material compliance rather than contaminant removal.
Does Australia have a PFAS limit in drinking water?
Yes. The National Health and Medical Research Council sets health-based guideline values for PFAS in the Australian Drinking Water Guidelines, and these were revised with lower, stricter limits.
| Substance | Current guideline value | Previous value |
|---|---|---|
| PFOS | 8 nanograms per litre | 70 ng/L (shared with PFHxS) |
| PFOA | 200 nanograms per litre | 560 ng/L |
| PFHxS | 30 nanograms per litre | 70 ng/L (shared with PFOS) |
| PFBS | 1000 nanograms per litre | Not previously set |
These figures come directly from the NHMRC's Australian Drinking Water Guidelines. The Department of Climate Change, Energy, the Environment and Water has also confirmed more than 700 PFAS contaminated sites nationally, concentrated around Defence bases and airports.
What certification does our whole-house filter actually have?
We stock AquaCo's whole-house PFAS filtration system, and we would rather give you the precise, checkable answer than a vague "certified" claim.
AquaCo holds genuine NSF International certification, verifiable on NSF's own public listing, for three standards: NSF/ANSI 42 (aesthetic effects), NSF/ANSI 58 (reverse osmosis systems) and NSF/ANSI/CAN 61 (component material safety). AquaCo also holds WaterMark Licence 23448, verifiable on the ABCB's WaterMark register, which lists the "Big Blue 20" x 4.5" Triple" model (Model ID SYS-203-WAWF) our whole-house system is built on.
NSF/ANSI 53, the standard that specifically covers PFOA and PFOS reduction, is not part of that NSF listing. We are not going to describe this filter as "NSF certified for PFAS," because that would not be accurate.
What the filter does have is independent laboratory testing. SGS, a third-party testing group, ran volume-based lifecycle testing on the filter's PFAS-reducing stage using EPA Method 537.1:2020, sampling water at start-up, 1500 litres and 3000 litres through the filter's life. The results showed PFOA reduced by more than 97.6% and PFOS reduced by more than 99.0%, tested against the same benchmark method the NSF/ANSI 53 protocol uses. That is genuine, independently verified performance data. It is tested to the standard's method, not certified under the standard itself.
If you want to see the filter this applies to, view our whole-house PFAS water filter, browse the PFAS Water Filters collection, or get a free installation quote if you want to talk through what your home needs.
Plumbed-in or countertop? Why that changes which certification matters
The certification you should check depends on how the filter connects to your water supply.
- Plumbed-in filters (under-sink, whole-house, inline): WaterMark is legally mandatory. Alongside WaterMark, check separately for an NSF/ANSI 53 PFOA/PFOS reduction claim if PFAS removal is the reason you are buying.
- Countertop, jug or gravity-fed filters: WaterMark does not apply, since nothing is being connected to household plumbing. Judge these purely on NSF performance certification, and check the specific model rather than the brand name generally.
Ask for the specific certification number or listing, not just the word "certified." A real listing can be looked up on NSF's public database or the ABCB's WaterMark register in a couple of minutes.
Do jug and fridge filters like Brita remove PFAS?
Not reliably, and not by default. Standard activated carbon jug and fridge filters are typically certified to NSF/ANSI 42 for chlorine taste and odour, or NSF/ANSI 53 for other specific contaminants such as lead. Removing PFAS is a separate claim that has to be tested and listed on its own. If PFAS removal matters to you, check the specific model's certification listing rather than assuming any filter with an NSF logo covers it.
We would rather show you a real certificate and a real lab result than ask you to take "certified" on faith. View our whole-house PFAS water filter, or read Do Water Filters Remove PFAS? if you are still weighing up whether filtration is worth it at all.
