26 terms · 26 of them cross-linked
Glossary
The vocabulary this site uses, defined plainly. Several of these words look like performance claims and are not: they name a material, a mechanism, a certifying body or a seller's adjective.
NSF/ANSI 42
The standard covering aesthetic effects in drinking water treatment units: chlorine taste and odor, and particulate reduction graded by particle size. Certification under it is claim by claim rather than blanket, so two products certified to 42 may hold different claims. Naming 42 says nothing about the 53 or 401 lists.
NSF/ANSI 53
The health effects standard for drinking water treatment units, covering reduction claims for contaminants the standard classes as health related, lead among them. A product is certified for the specific claims it was tested for, not for the whole standard. This site describes the scope of the standard and does not describe what any substance does to a person.
NSF/ANSI 42NSF/ANSI 401Contaminant reduction claimConsumer Confidence Report
NSF/ANSI 401
A separate standard covering a defined list of incidental contaminants and emerging compounds. It is a third scope rather than a higher tier, and a product can hold any combination of 42, 53 and 401. In this catalog every listing naming 401 also names the other two, which is a fact about four listings and not a rule.
IAPMO R&T
A certification body that tests and lists products against published standards, including drinking water treatment unit standards. Naming IAPMO on a listing tells you who issued a certificate, not which standard it was issued against. IAPMO publishes a searchable product listing database where the standard and the claims can be read.
WQA
The Water Quality Association, which operates a product certification program against the same published standards other bodies use. Like IAPMO, it is a certifier rather than a standard. Three listings in this catalog name WQA next to an NSF/ANSI mention that carries no number, which leaves the actual scope unstated.
Contaminant reduction claim
The unit a certification is actually issued in. A product is certified for named reduction claims under a standard, tested by a protocol, and the certifier publishes the list. "Certified to NSF/ANSI 53" is the headline; the claim list is the content, and it is the thing to look up when a specific substance is the reason you are shopping.
TDS
Total dissolved solids, a single meter reading of everything dissolved in water expressed as one number. It does not distinguish between substances, so a low reading and a high reading each cover many different compositions. A TDS figure on a listing is a measurement of one property, not a summary of water quality.
PFOA and PFOS
Two specific compounds in the wider PFAS group, named individually on several filter listings in this catalog. Where a listing names them it is making a reduction claim about those named compounds and nothing else. The EPA publishes information about PFAS, and that is the source to read rather than a product listing.
Contaminant reduction claimNSF/ANSI 401Consumer Confidence Report
Microplastics
Small plastic particles, named on three refrigerator filter listings here in the form of a 99% reduction figure. That percentage is not a claim under NSF/ANSI 42, 53 or 401, and it sits on listings that also name all three of those standards. It is a seller statement traveling next to certified ones.
Activated carbon
The filtration medium in most household drinking water filters, processed to give an enormous internal surface area that adsorbs certain compounds. Naming it describes what a cartridge is made of rather than what it has been certified to reduce. Those are different questions and only one of them has a certifier behind it.
Coconut shell carbon
Activated carbon made from coconut shell rather than from coal or wood, named on exactly one listing in this catalog. It is a sourcing and structure statement about the medium. No certification follows from the feedstock, and the listing that names it also names its standards separately.
Ion exchange
A filtration mechanism in which ions in the water are swapped for ions held on a resin. It is often combined with carbon in multi-stage cartridges. Like any mechanism, naming it says how a filter works rather than what it has been certified to reduce.
Gallon rating
A stated cartridge capacity in gallons, tested under a protocol rather than measured in your kitchen. It is more useful than a months figure because it can be divided by your own throughput. Where a manufacturer states both a gallon rating and a months figure, the practical rule is to replace at whichever arrives first.
Sediment
Suspended solid particles in water, the thing particulate reduction under NSF/ANSI 42 is graded against by particle size class. Sediment is also what shortens a cartridge life fastest, because it loads the medium physically rather than chemically. A visibly cloudy supply is a question for your utility.
Double-wall vacuum insulation
Two steel walls with the air evacuated from the gap between them, which removes conduction and convection across that gap. It is a construction claim: verifiable in a cutaway and stable across a production run. It is not the same kind of statement as a retention figure in hours.
Powder coat
A dry finish applied electrostatically and cured onto the outside of a vessel, giving grip and color. One tumbler listing in this catalog names it. It is an exterior treatment and it makes no claim about insulation, sealing or anything the drink touches.
Ceramic lining
An interior coating over the steel, named on two tumbler listings here. It changes the surface the drink is in contact with, which is a construction difference the listings state and then say nothing further about. Coatings can chip if the vessel is dropped.
Gasket
The silicone ring that makes a lid seal against the body. It lifts out of its groove, and the surface underneath is the one nobody looks at, which is why it belongs in every wash rather than in an occasional deep clean. Keep each gasket with the lid it came from, because swap lids share threads more reliably than seals.
Flip straw
A straw hinged into the lid so it folds flat when closed. It is better for carrying and worse for cleaning: a hinge, a tube and a seat, all of which hold water. Standing the parts up to drain after washing is the whole trick.
GasketWide mouth versus narrow mouthLeakproof versus leak-resistant
Cup-holder diameter
The measurement that would settle whether a tumbler fits a car, and which no listing in this catalog publishes. Sellers write cup-holder friendly, cupholder compatible or cup-holder fit instead, none of which carries a dimension. Measure the holder and measure the base; nothing on a listing page substitutes for it.
Wide mouth versus narrow mouthLeakproof versus leak-resistant
Wide mouth versus narrow mouth
A size family for the opening rather than a brand feature. A wide mouth takes standard ice cubes and a bottle brush and accepts more swap lids; a narrow mouth pours slower and fits pockets a wide body does not. Neither is a guarantee that a lid from one manufacturer threads onto another.
BPA-free
A statement made by a seller on a listing about a plastic component, not a certification mark and not verified here. Where a listing states it, this site records that the listing states it. The FDA publishes information on bisphenol A in food contact applications.
Leakproof versus leak-resistant
Two seller words with a real difference in strength and no test behind either. Leak-resistant and spill-resistant are the careful choices, usually made by sellers of straw lids. Neither claim names a condition such as inverted, full, or for how long, which is what would make it checkable.
Dishwasher safe
A manufacturer statement about whether a vessel tolerates a dishwasher cycle, stated on exactly one listing in this catalog. Where nothing is stated, nothing is permitted by default: the manufacturer instructions decide, and a top rack claim does not automatically cover a vacuum seal.
Boil water advisory
A notice from a utility or health department that water should be boiled before use. No household drinking water filter in this catalog replaces one. These filters are designed for water that is already fit to drink and are not intended for microbiologically unsafe water; when an advisory is in force, follow it.
Consumer Confidence Report
The annual report a community water system publishes describing what is in the water it delivers. It is the correct starting point for any question about your own supply, and the EPA explains what the reports contain and where to find yours. A product listing is not a substitute for it.
The standard numbers each have a page of their own at Standards, and the vessel words are argued out at Vessels.