How We Choose
the Products We Recommend

Recommendations first. Revenue second — and walled off from each other.

We choose every product, test, and professional on the merits alone: certification (NSF/ANSI, EPA-recognized, NELAP), how well it addresses the specific contaminant found at your address, and price-to-value. That decision is made in code that has no knowledge of whether a link earns us anything.

Some of those links are affiliate links, and some professional matches are paid referrals. When they are, the retailer or partner pays us — you pay the same price you’d pay going direct, and you land on the same product we’d have recommended regardless. We never take money to feature, rank, or include anything, and we never swap in a worse product because it pays more. If the best product for your situation has no affiliate program, we link it with no tag.

This is enforced structurally: selection happens first and independently, in the risk engine and product database (lib/data/products.ts); affiliate tracking is applied afterward by a separate layer (lib/data/affiliate-programs.ts) that cannot change what was chosen.

NSF/ANSI certification is the baseline.

For water filtration products, we require NSF/ANSI certification from an accredited third-party laboratory. We do not accept manufacturer self-testing claims. The relevant standards:

We match each finding to the NSF standard that covers its contaminant. A filter certified to NSF 53 for lead will only be recommended for a lead finding — not for a PFAS finding, even if the manufacturer makes broad claims.

For products without NSF certification (some test kits, EMF meters), we require EPA recognition, NELAP accreditation (labs), or NRPP certification (radon). We label uncertified products clearly as “third-party tested only.”

Contaminant-specific matching — not category-level.

Our reports are contaminant-specific. So is our product matching. A finding for trihalomethanes (TTHMs) will only surface filters certified to remove trihalomethanes — not a generic “water filter” that might address different contaminants.

Each product in our database declares which contaminant codes it addresses (e.g., TTHM, LEAD, PFAS). The matching is deterministic — no AI or language model is involved in deciding which product to recommend for which finding.

We recommend testing. Products are a complement, not a substitute.

For every finding where a lab test can definitively confirm or rule out a hazard — lead, PFAS, radon, nitrates — we recommend certified testing before purchasing filtration equipment. A filter is only as useful as the certainty that the contaminant is present.

We never recommend a product as a substitute for professional testing where testing is the EPA-recommended first step. We say this explicitly in every action card that pairs a test kit recommendation with a filtration recommendation.

Price range and accessibility.

Where a finding warrants protective action and multiple certified products exist, we include options across price ranges. We do not exclusively recommend premium products. Pitcher filters and under-sink systems certified to the same NSF standard are listed together.

Price ranges reflect manufacturer list prices at the time of our research (June 2026). We do not update prices in real time — always verify current pricing before purchase.

Research date and update cadence.

Our initial product database was researched and verified in June 2026 against manufacturer websites, NSF International's certified product listings, EPA-recognized product registries, and Amazon product pages. URLs were verified to be working and pointing to the correct product at the time of research.

Products are reviewed and updated periodically. If you find a broken link or a product that has been discontinued or de-certified, please email data@groundreport.app.

What we will never do.

• ✕Accept payment from manufacturers for inclusion or placement.
• ✕Let affiliate or referral revenue influence which products, tests, or pros we recommend.
• ✕Recommend a product for a contaminant it is not certified to remove.
• ✕Claim a product eliminates a risk — only that it reduces exposure.
• ✕Recommend a product instead of professional testing where testing is warranted.
• ✕Allow B2B relationships to influence which products are recommended to consumers.