What Do Clearbrook Filters Actually Remove? A Lab-Tested Contaminant Breakdown

Clearbrook's marketing understandably leads with big numbers: up to 99.9% of contaminants removed, including lead, PFAS, chlorine, and fluoride. Those claims may well be accurate, but they come from two very different sources of evidence, and knowing which is which matters if you're choosing a filter based on a specific concern. Here's the precise breakdown.

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What Clearbrook Is Actually Certified For

Clearbrook holds WQA certification to two NSF/ANSI standards. NSF/ANSI 42 covers "aesthetic effects," meaning taste, odor, and appearance rather than health-related contaminants; Clearbrook's certification under it covers chlorine taste and odor reduction plus a Class I particulate reduction claim. NSF/ANSI 372 covers lead-free construction materials, confirming the filter's own components don't leach lead into your water. Clearbrook is also independently tested to NSF/ANSI/CAN 401, a standard covering emerging compounds and incidental contaminants such as trace pharmaceuticals, personal care product residue, and similar substances.

These are real, accredited third-party certifications, and they mean something specific: an outside body reviewed Clearbrook's facility and test data for these exact claims. What they don't do is cover the full range of contaminants Clearbrook markets its filters as removing.

The Common Mix-Up: What NSF/ANSI 372 Actually Means

This is worth its own section because it trips people up constantly, not just with Clearbrook. "Lead-free materials" sounds like it means "removes lead," but it means the opposite kind of claim: the filter housing, seals, and components are certified not to add lead into your water as it passes through. Whether the filter also removes lead that's already present in your tap water is a separate question, answered by a different kind of testing entirely.

What's Based on Independent Lab Testing, Not Certification

Clearbrook's broader contaminant-removal claims, lead, PFAS, chlorine, VOCs, pesticides, and (via the separate PF2 filter) fluoride and arsenic, are based on the company's own independent lab testing rather than an NSF or WQA certification specific to each of those contaminants. This isn't unique to Clearbrook; it's the same evidentiary basis Black Berkey elements rely on for most of their published removal claims. Independent lab testing is a legitimate form of evidence, third-party labs really do run these tests, but it doesn't carry the same ongoing audits and facility inspections that formal certification requires.

Quick Reference: Certified vs. Independently Tested

Both columns represent real evidence. The difference is whether an accredited third party (WQA/NSF) formally certified the claim, or Clearbrook's own lab testing supports it.

Does This Mean the Broader Claims Are False?

No. Independent lab testing is real testing, and there's no evidence Clearbrook's broader claims are inaccurate. The point isn't that one type of evidence is fake and the other is real; it's that "certified" and "independently tested" mean different things, and marketing copy tends to blur that line. If a specific contaminant in your own water is a serious concern, whether lead, PFAS, or something else, that's worth confirming against Clearbrook's published lab data directly rather than assuming the general marketing claim covers it with certification-level rigor.

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