Editorial Standards
Last updated: April 2026
Every claim on this site is tied to a specific NSF/ANSI standard, EPA regulation, or manufacturer specification.
US Water Advisor publishes educational content about water in the modern world, specializing in filtration — how filter technologies work, what certifications mean, how to interpret water quality data, and how to make informed purchasing decisions. This page explains exactly how we produce content, what rules we follow, and where our information comes from. If anything on this site contradicts the standards described below, we want to know — contact us and we’ll fix it.
How We Research
Every article starts with primary sources. We do not use other blogs, review sites, or forums as source material. Our research process follows this sequence:
1. Identify the relevant standards and regulations. For any topic involving contaminant reduction, we start with the applicable NSF/ANSI standard document (42, 53, 55, 58, 401, P473, or others). For regulatory topics, we start with EPA publications — the Safe Drinking Water Act, National Primary Drinking Water Regulations, Consumer Confidence Report requirements, or the Lead and Copper Rule, depending on the topic.
2. Verify specific claims in official databases. Every contaminant reduction claim is checked against NSF’s public product database (info.nsf.org/Certified/DWTU/), WQA’s certification directory, or IAPMO’s listing. We do not cite reduction claims from manufacturer marketing materials unless those claims are independently verified by a certification body.
3. Cross-reference EPA data for regulatory context. When we reference MCLs (Maximum Contaminant Levels), action levels, or secondary standards, we verify the current values in EPA’s National Primary Drinking Water Regulations table. We cite specific numbers (e.g., “the EPA action level for lead is 15 ppb”) rather than vague characterizations.
4. Confirm mechanical and technical claims. When we explain how a filtration technology works (e.g., activated carbon adsorption, reverse osmosis membrane separation, UV disinfection), we verify the mechanism against NSF standard descriptions and established water treatment engineering references. We describe what the technology does mechanically, not what health outcomes it produces.
What We Will Never Do
These rules apply to every article on this site, without exception. They are not guidelines — they are hard limits.
We will never make health claims. No article on this site claims that a contaminant causes specific health effects or that filtration provides specific health benefits. We frame everything through mechanical, regulatory, and economic lenses. When a contaminant exceeds an EPA MCL, we state that it exceeds the MCL — we do not interpret what that means for your health. That’s a conversation for your doctor or your local health department, not a filtration website.
We will never use fear framing. You will not find phrases like “dangerous chemicals,” “toxic water,” or “contaminated tap water” on this site. We use neutral, factual language: “detected,” “present,” “above MCL,” “exceeds EPA action level.” Fear-based language sells filters. Data-based language helps you make informed decisions. We’re here for the second one.
We will never say a filter “removes” a contaminant. The correct term is “reduces.” No residential filter eliminates 100% of any substance. Certified reduction rates are defined in each NSF/ANSI standard, and we use the language those standards use.
We will never cite a contaminant reduction claim without a specific NSF/ANSI standard number. If we say a filter reduces lead, we say “certified to reduce lead per NSF/ANSI 53.” If we can’t cite the standard, we don’t make the claim.
We will never recommend uncertified products. In articles that include product recommendations, every recommended product holds current, verifiable third-party certification from NSF International, WQA, or IAPMO. No exceptions. No “honorable mentions” for uncertified products that seem good based on marketing claims.
We will never link to unofficial sources as references. Our source links go to NSF’s product database, EPA resources, and state health departments. Not to other blogs. Not to forums. Not to third-party review aggregators.
How We Handle Affiliate Revenue
Some articles on this site contain affiliate links. When you purchase a product through one of these links, we may earn a commission at no additional cost to you. Every article that contains affiliate links carries an FTC disclosure before the first affiliate link.
Affiliate relationships do not influence which products we recommend. Our recommendation criteria are certification-first: a product must hold verified third-party certification to the applicable NSF/ANSI standard before we consider it. Products are evaluated on certification scope, certified capacity, total cost of ownership, and format suitability — not on which retailer offers the highest commission rate.
Foundation articles (our educational guides explaining how technologies work, what standards mean, and how to read your water data) contain zero affiliate links and zero product recommendations. These articles exist to build your knowledge base, not to sell you anything.
Our Source Standards
Every article ends with a “Sources & Standards Referenced” section listing the specific official sources used. The only sources we cite are:
| Source Type | Examples |
|---|---|
| NSF International | NSF/ANSI standards (42, 53, 55, 58, 44, 401, P473), NSF product database (info.nsf.org/Certified/DWTU/) |
| EPA | Consumer Confidence Reports (epa.gov/ccr), National Primary Drinking Water Regulations, Safe Drinking Water Act, Lead and Copper Rule, private well guidance |
| Other certification bodies | WQA (wqa.org), IAPMO (iapmo.org) — ANSI-accredited bodies that certify to the same NSF/ANSI standards |
| State agencies | State health departments, state environmental agencies — for well water testing guidance and certified lab referrals |
| Manufacturer specifications | Replacement intervals, capacity ratings, installation specs — cited as manufacturer recommendations, not independent claims |
We do not cite other water filter blogs, Amazon reviews, Reddit threads, or unattributed industry reports. If we can’t trace a claim to an official standard, regulation, or manufacturer specification, we don’t publish it.
How We Handle Corrections
If we publish something that’s wrong — a misquoted standard number, an outdated EPA regulation, a certification claim that doesn’t match the NSF database — we want to fix it. Contact us with the specific error and the correct source, and we’ll update the article, note the correction, and update the “Last updated” date.
We do not silently edit published content to change meaning. Factual corrections are noted. Style and clarity edits are made without notation.