What we changed — and why

We told carers to clean the bidet nozzle on a schedule. We left out the part where that isn't enough.

Our care guidance said self-cleaning helps but isn't a substitute, and that the nozzle needs a fixed cleaning schedule. That is still true. What we didn't say is what cleaning the nozzle doesn't do.

A 2019 survey of 192 bidet seats in a Japanese hospital compared daily against weekly scrubbing. Daily scrubbing roughly halved the share of heavily contaminated nozzle surfaces — and changed nothing measurable about the bacteria in the sprayed water. Cleaning the outside doesn't reach the inside. Someone caring for a person with a serious infection risk could reasonably have read our old wording as "scrub it and you've handled it", and that reading was available because we left the gap open.

We have added the missing half, and with it the one design difference that does have measurements behind it: seats holding a warm-water reservoir carry substantially more bacteria in the spray than seats that heat on demand, apparently because the chlorine protecting mains water dissipates while the water sits. We now say to prefer an on-demand heater for a vulnerable user.

Two limits we have put on the page rather than in a footnote, because they change how much weight the advice can carry. Most of this research comes from one Japanese group funded by the bidet industry's own trade association. And not one of these studies was done in an ordinary home — every single one was a hospital or a university campus, which is the harsher setting. We are reporting the best evidence that exists, not evidence that is good enough.

Claim HYG-NOZ-014 moved to contested after a structured literature search surfaced PMID 36216567, which partially contradicts the 2019 survey we had relied on.

On the same pass we weakened a recommendation we had been making to businesses. We had written that a self-rinsing or retractable nozzle "earns its money" in shared washrooms. The reasoning still looks sound to us, but there is no standard for self-cleaning performance and no independent test of it, so the claim rests on the manufacturer's word alone. It now reads as an engineering argument with that stated plainly, not as a recommendation. Where it changes anything commercially, it points people at cheaper units.

We said the Waterdrop G3P800 was certified for one thing. It is certified for six, including lead.

Our water pages stated that this unit's IAPMO certification covered a single line — total dissolved solids — and we used that to keep it out of our recommendation for documented lead. We took that from a certificate PDF dated March 2023, hosted on the manufacturer's own server.

On 8 August 2026 we opened the live IAPMO R&T listing instead. File WC-13976, issued to Qingdao Ecopure Filter Co. Ltd, certified to NSF/ANSI 58-2024, status active. Model WD-G3P800 carries certified reduction claims for TDS, fluoride, cadmium, barium, radium 226/228 and lead. The listing is here. We were understating it.

Two things follow. The unit now appears as a certified option for documented lead alongside the pitcher, and the whole-house filter we previously showed on that path has been removed from it — it is certified for lead by nobody, which we have said since July. And we have stopped repeating retail claims to NSF/ANSI 42 and 53: those standards do not fall under this file.

A manufacturer's PDF is not a certification database, and we should not have treated it as one — in either direction. Where a listing has changed, the entry here changes with it, whichever way it cuts.

Our bidet "main pick" is now a "popular low-cost option" — because of the unresolved backflow question.

On 3 August we documented that the LUXE NEO 185 Plus, which we recommended as our main pick, does not document any backflow protection and does not appear in an official plumbing listing we could find. Leaving it labelled "main pick" while that question stands was inconsistent with how we work.

The product is still shown — it remains a popular, low-cost entry point and the verification gap is stated right next to it — but it is no longer presented as our default recommendation. If we find a comparable attachment with documented backflow protection, it becomes the lead option.

The Sleep Math is parked and de-listed until its recommendations are verified.

The sleep calculator was presented on our homepage alongside the finished tools, while its product recommendations, trial-period and return-term checks are not done. That quietly suggested a level of vetting it does not yet have.

The page stays online for anyone who has the link, but it is removed from the homepage line-up and from our sitemap, and marked not-for-indexing, until specific mattresses, their return conditions and their affiliate terms have actually been checked.

We recommended a whole-house filter for lead. It is certified by nobody.

For documented lead in drinking water, our water calculator led with a $400 whole-house system. We had described it the way the retail listing does — as a lead-reducing system.

Checking the certifiers directly, no listing exists for it with NSF, IAPMO or the WQA. iSpring does hold genuine NSF certification, but on its reverse-osmosis units, which are different products. Home Depot's own specification table for this model reads "No Certifications or Listings". And the manufacturer's "tested by an independent third party" line covers stages one and two — not stage three, the lead filter itself, which is the only reason to buy that model.

We also found the reverse-osmosis unit we offered as the alternative holds a certification covering exactly one thing: total dissolved solids. Its lead and PFAS figures are laboratory tests, not certified claims.

The calculator now routes documented lead and PFAS to a $35 filter pitcher, which turned out to be the only product on the page with a listed certification naming those substances — lead 98.8%, PFOA and PFOS 99.8%. For arsenic and nitrate it now says none of our products is certified for either and sends people to the NSF database instead.

We called an air purifier "independently AHAM-verified". It is not in the register.

Our default air purifier pick carried the phrase "independently AHAM-verified". We could not find that model, or either of the other two we recommend, in the AHAM Verifide directory. Of the three, the one carrying the claim had the least independent backing.

The phrase is gone. In its place, each page now states where every number comes from: the largest unit's 391 CFM is confirmed as its smoke CADR in the ENERGY STAR registry, and the two smaller figures rest on the manufacturer's own documentation, which does not even say which of the three CADR types it is publishing.

The numbers themselves stood up — nothing was contradicted. And the check produced something we did not expect: our arithmetic turns out to be within half a percent of AHAM's own room-size formula, and the threshold above which one unit is no longer enough now rests on a government registry rather than a manufacturer's spec sheet.

Our free widget carried shopping links it should never have had.

We built an embeddable version of the air calculator for other sites to put on their own pages. It contained three affiliate links. Amazon's terms only permit their links on sites an associate has registered — so every site that embedded our widget would have been publishing a breach on its own page, with our tag on it.

All three links are gone. The button under the result now opens our own calculator. The widget carries no shopping links, no cookies and no analytics of any kind, and the terms page explains why rather than hiding it.

Our best-selling bidet pick documents no backflow protection.

Plumbing codes treat bidets as a specific case: the water supply must be protected against backflow, by an air gap or an appropriate backflow preventer. It is the one genuine safety question in the category.

Our main pick — a $56 attachment — documents no backflow protection at all. No vacuum breaker, no check valve, nothing in the manual or on the product page. Its maker does not appear in IAPMO's listee index, and what looks like a certification in the manual is in fact a partial list of test sections. Our budget option is the same, citing a 2009 edition of the standard that has since been superseded twice.

This is not evidence that either is unsafe, and no recall exists for them. It means the protection has to come from the plumbing, and nobody selling them mentions it. That now appears above the buy button rather than in a footnote. On the business page, where a facilities manager may be fitting twenty of them in an inspected building, it appears before the payback arithmetic instead of after.

The audit also moved something the other way. The $410 electric seat we recommend for care at home turned out to be the best-documented product anywhere on this site: listed by model name in IAPMO's electrical directory, with both a vacuum breaker and a check valve in its manual, and a spray temperature capped below the code limit. Its own warnings about scalding and about never using the seat as a support are now quoted directly, because they are better than ours were.

We looked at smart toilets that claim to spot illness. None holds an FDA clearance.

We checked five toilet-based health monitors against the manufacturers' own documents and the FDA's databases. One manufacturer's genuine FDA clearances turned out to be for a heart monitor, not the urine device people assume they cover. Another company's urine test strips were recalled by the FDA in 2026, with the cause recorded as "No Marketing Application".

The resulting page carries no affiliate link and no buy button, and says that if you want to know whether you have a disease, none of these is the answer. We are not in any of these affiliate programmes and did not apply.