Water
The solvent almost all cleaning happens in, and on its own the right answer more often than it is given credit for.
What not to do
Water is unsafe on Finished wood flooring
Unsafe
Do not do this. The risk is established, and it is described below.
The hazard is standing water rather than damp. Wet mops and steam mops are ruled out by the trade association entirely.
Precautions
- Check the manufacturer's instructions
Evidence
Supported
Sources
Maintenance, and How to Clean and Take Care of Your Wood Floors
National Wood Flooring Association (NWFA) · Trade or professional body
Relied on for: That wet mops and steam mops must not be used because they will damage the finish and the wood over long periods, and that wet mopping puts too much water on the floor which penetrates through seams into deeper layers. (states this directly)
Water is unsafe on Upholstery fabric
Unsafe
Do not do this. The risk is established, and it is described below.
For panel and workspace cloth specifically. Not every sofa fabric — but the assumption that water is always the gentle option fails here.
Precautions
- Test on an inconspicuous area first
- Check the manufacturer's instructions
Evidence
Supported
Sources
Materials: Textiles Care and Maintenance
Herman Miller, Inc. · Manufacturer documentation
Relied on for: That water or any liquid solution must not be applied to the panel cloth, because wetting the fabric with any liquid solution may result in permanent damage. (states this directly)
Water is unsafe on Viscose and rayon
Unsafe
Do not do this. The risk is established, and it is described below.
Three separate mechanisms: poor wet strength, dyes that bleed on contact with moisture, and water-soluble sizing whose loss distorts the garment.
Precautions
- Test on an inconspicuous area first
- Check the manufacturer's instructions
- Consider professional help
Evidence
Strongly supported
Sources
Drycleaning & Laundry Institute International (DLI) · Trade or professional body
Relied on for: That with the exception of lyocell rayon is very sensitive to water, that many of its dyes bleed or migrate on contact with moisture, and that water-soluble sizing means washing will distort the shape of the garment. (states this directly)
Unsafe
Do not do this. The risk is established, and it is described below.
Evidence
Strongly supported
Sources
Tempur Sealy International · Manufacturer documentation
Relied on for: That mattresses should never get wet, that waterproof covers and encasements are recommended, and that a mattress which does get wet is towelled and air-dried. (states this directly)
Unsafe
Do not do this. The risk is established, and it is described below.
Immersion specifically. The manual's prohibition covers water and the dishwasher together, and it sits under an electric-shock heading.
Evidence
Supported
Sources
Bosch Compact Toaster TAT6A913IN Instruction Manual
Robert Bosch Hausgeräte GmbH · Manufacturer documentation
Relied on for: That the appliance must never be immersed in water or placed in the dishwasher, and that it must not be steam-cleaned, stated under a danger-of-electric-shock heading. (states this directly)
Water is unsafe on Window hardware
Unsafe
Do not do this. The risk is established, and it is described below.
Unusually, plain water is the prohibited agent here, and it sits inches from a surface that is cleaned with soapy water.
Evidence
Supported
Sources
PVC-U Window & Door Systems: Handling, Installation, Maintenance and Care Guide
The VEKA UK Group (VEKA and Halo profile systems), 2014 · Manufacturer documentation
Relied on for: That external hardware is cleaned by wiping with a dry soft duster, and that water is not to be used on it. (states this directly)
Water is unsafe on Memory foam
Unsafe
Do not do this. The risk is established, and it is described below.
The manufacturer leads with this rather than with a method. An open-cell foam takes in whatever is used on it and dries from the inside outwards.
Evidence
Supported
Sources
Tempur Sealy International · Manufacturer documentation
Relied on for: That mattresses should never get wet, that a mattress which does get wet is towelled to remove excess moisture and then air-dried, and that stain cleaning is mild soap with cold water applied lightly and only if unavoidable. (states this directly)
Best avoided
The available guidance advises against this.
The failure modes are listed rather than implied: shrinkage, fading, dye bleeding, loss of shape, and a limp or rough texture.
Evidence
Supported
Sources
Drycleaning & Laundry Institute International (DLI) · Trade or professional body
Relied on for: That silk is highly sensitive to moisture, that washing it at home can cause shrinkage, fading, dye bleeding, loss of shape and a limp or rough texture, and that silk generally responds best to professional drycleaning. (states this directly)
Water is prohibited by the manufacturer for Blind headrail
Best avoided
The available guidance advises against this.
The exclusion inside the permission. Whatever the slats are made of, the rail with the mechanism in it does not go in the water.
Evidence
Supported
Sources
How to Clean Blinds, and How to Clean Wood Blinds
Hunter Douglas · Manufacturer documentation
Relied on for: That headrails on the cordless, motorised, retractable-cord and glide operating systems must not be immersed, and neither must the bottom rail on the lift system that carries its mechanism there. (states this directly)
Water is unsafe on Memory foam
Unsafe
Do not do this. The risk is established, and it is described below.
Already true of mattresses, and this is a second body saying it for a different product made of the same material.
Evidence
Strongly supported
Sources
How To Wash Pillows At Home Like an Expert
Bed Advice UK — The National Bed Federation · Trade or professional body
Relied on for: That foam pillows should be cleaned by wiping them rather than washed, in a document that permits machine washing for every other filling it names. (states this directly)
Tempur Sealy International · Manufacturer documentation
Relied on for: That memory foam should never get wet and that an item which does get wet is towelled to remove excess moisture and then air-dried. (states this directly)
Unsafe
Do not do this. The risk is established, and it is described below.
The identification is the hazard. Alabaster is gypsum and readily water soluble; marble is calcite and is not. They are routinely confused, and both are sold as onyx.
Evidence
Supported
Sources
Conserve O Gram 15/1: Care of Alabaster
National Park Service, US Department of the Interior, 2000 · Government or regulator
Relied on for: That alabaster is the fine-grained form of gypsum, that it is readily water soluble while marble is not, and that moisture contact of any kind is to be avoided. (states this directly)
Water is unsafe on Cellulose nitrate
Unsafe
Do not do this. The risk is established, and it is described below.
Evidence
Supported
Sources
Conserve O Gram 8/4: Care and Identification of Objects Made from Plastic
National Park Service, US Department of the Interior · Government or regulator
Relied on for: That solvents and water must not be used to clean plastic, and that if in-depth cleaning is needed a conservator should be consulted. (states this directly)
Water is unsafe on Cellulose acetate
Unsafe
Do not do this. The risk is established, and it is described below.
Evidence
Supported
Sources
Conserve O Gram 8/4: Care and Identification of Objects Made from Plastic
National Park Service, US Department of the Interior · Government or regulator
Relied on for: That solvents and water must not be used to clean plastic, and that if in-depth cleaning is needed a conservator should be consulted. (states this directly)
Water is unsafe on Casein plastic
Unsafe
Do not do this. The risk is established, and it is described below.
Evidence
Supported
Sources
Conserve O Gram 8/4: Care and Identification of Objects Made from Plastic
National Park Service, US Department of the Interior · Government or regulator
Relied on for: That solvents and water must not be used to clean plastic, and that if in-depth cleaning is needed a conservator should be consulted. (states this directly)
Water is unsafe on Phenolic plastic
Unsafe
Do not do this. The risk is established, and it is described below.
Evidence
Supported
Sources
Conserve O Gram 8/4: Care and Identification of Objects Made from Plastic
National Park Service, US Department of the Interior · Government or regulator
Relied on for: That solvents and water must not be used to clean plastic, and that if in-depth cleaning is needed a conservator should be consulted. (states this directly)
Water is unsafe on Polyurethane foam
Unsafe
Do not do this. The risk is established, and it is described below.
Evidence
Supported
Sources
Conserve O Gram 8/4: Care and Identification of Objects Made from Plastic
National Park Service, US Department of the Interior · Government or regulator
Relied on for: That solvents and water must not be used to clean plastic, and that if in-depth cleaning is needed a conservator should be consulted. (states this directly)
Water should be avoided for Suede
Best avoided
The available guidance advises against this.
A damp cloth is the most the maker permits, and it warns the colour will darken until it dries. Soaking is not a stronger version of the same thing.
Evidence
Supported
Sources
Shoe Care Tips: Nubuck and Suede
KEEN Footwear · Manufacturer documentation
Relied on for: That the nap can be damaged by water, that suede and nubuck absorb water because of the rough surface, and that a damp cloth darkens the colour until it dries. (states this directly)
Water is unsafe on Fridge shelf
Unsafe
Do not do this. The risk is established, and it is described below.
Warm water on a COLD glass shelf. The shelf can break, and tempered glass breaks into pebbles all at once.
Evidence
Supported
Sources
Cleaning the Shelves - Refrigerator
Whirlpool Corporation · Manufacturer documentation
Relied on for: That glass shelves must not be cleaned with warm water while cold because they may break from sudden temperature change, and must be allowed to reach room temperature before applying warm soapy water and dried thoroughly. (states this directly)
In detail
Water dissolves polar and ionic substances — sugar, salt, many food residues — and carries away anything already loose. It cannot lift oils and fats, because it is polar and they are not, which is the single limitation that most other cleaning agents exist to overcome. Water's own composition changes what it does. Hard water carries dissolved calcium and magnesium, which react with soaps and reduce the effectiveness of some surfactants, and which leave mineral deposits behind on evaporation. Temperature matters too: hot water lowers the viscosity of fats and speeds most chemical processes, which is a real effect rather than a folk belief. Because water is the medium, it is also the thing that carries residues away at the end, and inadequate rinsing leaves cleaning agents in contact with a surface far longer than intended.
Properties
- Chemical name
- Water
- pH
- Approximately neutral
What works
Water is effective against Sugar and lactose residue Supported
The only soil that needs no chemistry at all — while it is still sugar.
Water is safe on, in specific conditions, Microwave turntable
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
The manufacturer permits the dishwasher and forbids only the timing.
Only within these limits:
- Not placed into water just after cooking, while the glass is still hot
- Warm sudsy water once it has cooled
- The dishwasher is explicitly permitted as an alternative
The instruction is about timing rather than about the water. A hot glass plate meeting cold water is the failure the manufacturer names, and it is the same mechanism that cracks a casserole dish.
Precautions
- Do not apply to a hot surface
Evidence
Supported
Sources
Owner's Manual: Microwave Oven, models JEM31 and PEM31
GE Appliances · Manufacturer documentation
Relied on for: That the turntable must not be placed into water just after cooking, to prevent breakage, and that it is washed in warm sudsy water or in the dishwasher. (states this directly)
Water is safe on, in specific conditions, Finished leather
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- deionised water, because minerals in hard water may leave rings
- a DAMPENED cloth rather than a wet one — the leather is not soaked
- applied to the cloth, never poured or sprayed onto the leather
- gentle circular rubbing, feathering the edges, with no more force than a firm handshake
- air dried, with no heat applied
The force limit is the guide's own and is unusually memorable: scrubbing damages the leather AND makes the stain harder to remove.
Precautions
- Test on an inconspicuous area first
- Check the manufacturer's instructions
Evidence
Supported
Sources
Leather Care and Cleaning Guide
The Leather Institute, 2011 · Trade or professional body
Relied on for: That deionised water is specified because hard water minerals may cause rings, that water-based soil is treated by dampening a cloth rather than soaking, that cleaner is applied to a rag and never directly to the leather, that no more force than a firm handshake should be used, and that leather is air dried with no heat. (states this directly)
Water is safe on, in specific conditions, Straightener plate
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- UNPLUGGED — not merely switched off
- Completely COOL, which the manual repeats under storage as well as cleaning
- A damp cloth, wrung out; never a poured or sprayed liquid and never immersion
The manual's own water warnings are stronger than this and are about a different moment: near a bath, shower or basin the appliance is a hazard even when it is switched off. That is about proximity to water while it is plugged in, not about a wrung-out cloth on a cold, unplugged one.
Precautions
- Disconnect from the power supply first
- Do not apply to a hot surface
Evidence
Supported
Sources
Keratin Protect Intelligent Straightener S8598 — instruction manual
Spectrum Brands (UK) Ltd, trading as Remington · Manufacturer documentation
Relied on for: That the appliance is unplugged and allowed to cool, that all the surfaces are wiped with a damp cloth, and separately that it must not be used near bathtubs, showers, basins or other vessels containing water and must be unplugged after use in a bathroom. (states this directly)
Water is safe on, in specific conditions, Laminate flooring
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- A WELL-WRUNG damp cloth. Not a wet mop and not a wet floor
- Vacuum the loose dirt off first — grit is described as acting like sandpaper
- A laminate cleaner added to the water rather than a general-purpose product
- NO STEAM. The bulletin's statement is flat and unqualified: steam cleaners are not suitable for use with ANY type of laminate floor
Laminate has a WOOD-BASED CORE. The trade body states that higher humidity makes wood-based panels swell and low humidity makes them shrink, which is why the water instruction is about quantity rather than about chemistry.
Precautions
- Check the manufacturer's instructions
Evidence
Supported
Sources
Technical Bulletin: Cleaning and Maintenance of Laminate Floor Coverings in the Home
EPLF — Association of European Producers of Laminate Flooring, 2022 · Trade or professional body
Relied on for: That cleaning is by vacuum for loose dirt and a well-wrung damp cloth with a laminate cleaner added to the water, that steam cleaners are not suitable for use with any type of laminate floor, and that wood-based panels swell with higher humidity and shrink with low humidity. (states this directly)
Water is safe on, in specific conditions, Architectural bronze
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- De-ionised or distilled water is preferred ON THE BRONZE, because it is more aggressive
- NOT where the plaque is mounted on polished stone, marble, limestone or concrete — it can etch them
- Substrate beneath kept flooded with clean tap water throughout
The purity of the water is a variable rather than a detail, and it points in opposite directions for the metal and for what the metal is fixed to.
Evidence
Supported
Sources
Conserve O Gram 10/5: Caring for Outdoor Bronze Plaques, Part II — Cleaning and Waxing
National Park Service, US Department of the Interior · Government or regulator
Relied on for: That de-ionised or distilled water is more aggressive for cleaning than tap water and is recommended for use on bronze plaques, and that it should not be used for cleaning plaques mounted on highly polished stone, marble, limestone or concrete as the water can cause slight surface etching. (states this directly)
Water is safe on, in specific conditions, Mirrored glass
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- Clean WARM water on a soft lint-free cloth, wrung out
- Dry the mirror immediately
- Keep liquid off the edges — wet edges cause the damage known as black edge, and any that do get wet are dried immediately
- Never spray onto the mirror; apply to the cloth, specifically so it cannot reach the edges
The trade body calls plain warm water the very best and safest cleaner for a mirror, and prohibits the commercial mirror cleaners containing ammonia or vinegar that most people reach for.
Precautions
- Rinse thoroughly afterwards
Evidence
Supported
Sources
Glass Technical Paper FB06-05: Proper Procedures for Cleaning Flat Glass Mirrors
National Glass Association (NGA), Mirror Division, 2019 · Trade or professional body
Relied on for: That the very best and safest cleaner for a mirror is clean warm water on a soft lint-free cloth wrung out with the mirror dried immediately, that cleaner must not be sprayed directly onto the mirror, and that wet edges cause black edge damage. (states this directly)
Water is safe on, in specific conditions, Toaster
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- Pull the power plug and let the toaster cool down FIRST
- A damp cloth on the exterior only
- NEVER immerse the appliance or put it in the dishwasher
- No steam cleaning; no oven or grill spray
- Crumb tray removed and wiped; crumbs under the warming rack taken out with a firm brush
The two conditions are stated together under a danger-of-electric-shock heading rather than under cleaning, which is where the priority is set.
Precautions
- Disconnect from the power supply first
- Do not apply to a hot surface
Evidence
Supported
Sources
Bosch Compact Toaster TAT6A913IN Instruction Manual
Robert Bosch Hausgeräte GmbH · Manufacturer documentation
Relied on for: That the plug is pulled and the toaster allowed to cool before cleaning, that it must never be immersed or placed in the dishwasher, that steam cleaning and oven or grill spray are prohibited, and that the exterior is cleaned with a damp cloth. (states this directly)
Water is safe on, in specific conditions, Shaving brush
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- Lukewarm, and only to rinse the suds out — this is not a soak
- Shake the excess out gently rather than squeezing or wringing the knot
- Store BRISTLE DOWN on a stand so gravity takes the water away from the handle
- Away from direct heat and direct sunlight
The one brush here that water is cleared on, and the clearance is really about the drying: a knot left standing upright holds water against the adhesive and the handle.
Evidence
Strongly supported
Sources
G.B. Kent & Sons plc (Kent Brushes) · Manufacturer documentation
Relied on for: That the suds are rinsed off in lukewarm water, that excess water is gently shaken off, and that the brush is stored bristle down on a stand, away from heat and sunlight. (states this directly)
Water is safe on, in specific conditions, Detergent drawer
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- Warm RUNNING water, with the inserts taken out first
- A soft brush for excessive build-up
- By hand only — the dishwasher is prohibited for these parts
- Every two to four weeks with frequent use, or sooner in hard water
Evidence
Supported
Sources
How to Clean a Front Load Washer Dispenser (Drawer)
Whirlpool Corporation · Manufacturer documentation
Relied on for: That the dispenser drawer is removed and washed under warm running water with a soft brush, that the housing is cleaned with mild soap and a soft cloth, and that removable parts must not be cleaned in the dishwasher. (states this directly)
Water is safe on, in specific conditions, Dishwasher filter
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- Rinse under running water until most soils are gone
- A SOFT brush only, and only for stubborn soil or hard-water deposits
- Air dry or pat dry before refitting
- Refit until it locks — if the upper assembly turns freely it is not seated
- Monthly, or fortnightly if the machine runs daily
The refitting check is part of the cleaning. A filter left unlocked is the same as a filter left out.
Precautions
- Check the manufacturer's instructions
Evidence
Supported
Sources
How to Clean the Dishwasher Filters
Whirlpool Corporation · Manufacturer documentation
Relied on for: That the filter is rinsed under running water with a soft brush for calcium deposits, that a wire brush or scouring pad must not be used, that it must be locked back into place, and that the dishwasher must not be operated without the filters installed. (states this directly)
Why
- Water is explained by Water purity and aggressiveness
- Water is explained by Why the recommendation is usually the mild one
Aftercare and prevention
- Water requires the aftercare Dishwasher filter
Refit it and check it locks. Running the machine without the filters properly installed causes damage.
Hacks and claims involving this
- Steam mops are safe on sealed wood floors Does not work
- Pouring boiling water down a drain Disputed
When the obvious answer is wrong
How do I get hard water spots off a bathroom mirror without wrecking it?
A mirror is not a pane of glass. It is glass with a reflective coating and a protective backing, and both are exposed at every edge. The glass industry's mirror division states that acid or alkali cleaners can attack the front surface, the edges and the backing, and names cleaners containing ammonia or vinegar specifically as ones not to use. The failure is called black edge, it starts where liquid runs into the perimeter, and it is degradation of the mirror rather than dirt on it.
A different kind of treatment works: Change the mechanism from dissolving to drying. The mirror division's own recommendation is clean warm water on a soft lint-free cloth, wrung out, with the mirror dried immediately afterwards — which works because the deposit is created at the moment of evaporation rather than while the water sits. Apply any liquid to the cloth and never spray it at the mirror, so nothing can run down into the edges, and finish by checking that the joints and edges are dry. Where a mark will not come off with water, the paper's stated method is 0000 oil-free steel wool, explicitly not a solvent, since solvents attack the edges and backing too. The prevention is the whole answer in a bathroom: ventilate, and wipe the mirror dry rather than letting the condensation evaporate on it.
Sources for this page
Sources
Handbook of Detergents (Surfactant Science Series)
CRC Press / Taylor & Francis · Reference work
Relied on for: That water hardness reduces detergency through interaction of calcium and magnesium ions with surfactants.