{"content_id":"lie3qh9vax","slug":"humidifier-water-tap-filtered-distilled-guide","locale":"en","schema_type":"Article","category":"knowledge_base","category_name":"Knowledge Base","title":"Humidifier Water: Tap vs. Purified Water Guidelines","summary":"Choose water for your humidifier based on the water requirements in the product manual. Understanding how mineral content varies by purification method, along with the separate roles of water changes and cleaning, helps explain conflicting guidance on tap water and purified water.","sponsorship_disclosure":null,"affiliate_disclosure":null,"commerce_disclosure":null,"author":{"name":"Injoys Editorial Team","url":"https://injoys.com/ko/about"},"key_points":["The humidification method alone does not determine which water to use; check the water requirements for your specific model.","Even water from a water purifier varies in mineral content depending on the treatment method.","White dust on nearby furniture and hard deposits inside the tank occur in different places.","Even when using water with low mineral content, you still need to change the water and clean the tank.","Water that has been boiled and cooled is different from distilled water made by collecting the steam separately."],"content_markdown":"Choose water for a humidifier based on what the product manual specifies. Water from a purifier also varies in mineral content depending on the treatment method. Ultrasonic humidifiers can disperse substances in the water into the air. Whatever water you use, you still need to change it and clean the tank.\n\nThe water replacement schedule is based on the CDC's March 15, 2024 guidance.\n\n## What water should you use?\n\nCheck the water requirements in your model's manual to find out which water you can use. The name of the water alone does not tell you whether it suits every product. Read both the manufacturer's conditions for product use and public health agencies' care recommendations.\n\nIRIS OHYAMA specifies tap water in its FAQ. It cites the suppression of microbial growth by residual chlorine as the reason. It advises against using water from a purifier or similar sources. This is that manufacturer's guidance, not a rule for all products. [IRIS OHYAMA water supply FAQ](https://www.irisohyama.co.jp/support/faq/detail.php?ID=442)\n\nBy contrast, the EPA, the United States Environmental Protection Agency, recommends water with a low mineral content. The aim is to reduce mineral emissions from ultrasonic and similar humidifiers. You should therefore not switch to distilled water on your own if your product specifies tap water. If the instructions conflict, check with the manufacturer using your model name. [EPA guidance on using and caring for home humidifiers](https://www.epa.gov/indoor-air-quality-iaq/use-and-care-home-humidifiers)\n\n## Comparing ultrasonic, steam, and evaporative humidifiers\n\nHow substances in water move into the air depends on the humidification method. These devices add moisture to the air to raise indoor humidity. Methods that release water droplets must be distinguished from those that evaporate water.\n\n| Type | How it releases moisture | Water and care considerations |\n| --- | --- | --- |\n| Ultrasonic | Uses vibration to create fine water droplets | Minerals and microorganisms in the water can be dispersed along with the droplets |\n| Steam | Heats water to produce water vapor | Be careful of burns from hot water and steam |\n| Evaporative | Passes air through a wet filter or similar material to evaporate water | Filters and areas where water collects need care |\n\nThe EPA explains that steam and evaporative humidifiers release fewer minerals. This does not mean they need no internal care. For hybrid models, check the actual humidification mechanism rather than relying on the name. [EPA explanation of humidifier types](https://www.epa.gov/system/files/documents/2022-07/Use%20and%20Care%20of%20Home%20Humidifiers.pdf)\n\n## Comparing tap, purified, bottled, and distilled water\n\nThe treatment method provides a more specific basis for judgment than the name under which water is sold. The word “purified” does not mean that minerals have been removed. The CDC explains that different filters remove different substances. Check the purifier manual and filter labeling for actual performance.\n\n| Type of water | Distinguishing characteristics | What to check before filling |\n| --- | --- | --- |\n| Tap water | Not sterile even if it meets drinking water standards | Whether the product allows its use and any local water quality notices |\n| Water treated with activated carbon | Mainly used to improve taste and odor | Whether mineral removal performance is separately specified |\n| Water treated by reverse osmosis | Uses a membrane to reduce dissolved substances | The substances actually removed, such as calcium and magnesium |\n| Bottled water | Being bottled does not mean it is low in minerals | The mineral content label and whether the manufacturer allows its use |\n| Distilled water | Made by collecting steam from boiling water and turning it back into liquid | Whether the product allows its use and whether it contains additives |\n| Boiled and cooled water | Water that has been heated and then left to cool | Do not treat it as equivalent to distilled water |\n\nReverse osmosis is a water purification method also called RO. The CDC explains that this method can reduce calcium, magnesium, and other substances. However, the removal performance of each product needs to be checked. Purifier filter replacement also needs attention. [CDC guide to home water filters](https://www.cdc.gov/drinking-water/prevention/about-choosing-home-water-filters.html)\n\n## Why do standards differ for drinking water and water dispersed as mist?\n\nBeing safe to drink does not by itself establish suitability for misting. Swallowing water and inhaling fine water droplets are different. The CDC also explains that drinkable tap water is not sterile. This distinction is often overlooked when choosing water. [CDC guidance on preventing waterborne germs at home](https://www.cdc.gov/drinking-water/prevention/preventing-waterborne-germs-at-home.html)\n\nThe following criteria address different issues.\n\n- Drinking suitability concerns whether water can be used for drinking.\n- Mineral content is related to the formation of white dust and hard deposits.\n- Microbial control includes water storage and device cleaning.\n- Product compatibility concerns the water supply conditions allowed by the manufacturer.\n\nBottled water is therefore not better suited to filling a humidifier simply because it costs more. Nor does using purified water remove the need to care for the tank. Meeting one criterion does not mean that the other conditions have been met.\n\n## How do white dust and deposits inside the tank differ?\n\nWhite dust that settles nearby must be distinguished from deposits that adhere to the tank. The CPSC, the United States Consumer Product Safety Commission, explains the two phenomena separately. Even when the same minerals in the water are involved, they appear in different places.\n\n| What you observe | Possible cause | Cautions when interpreting it |\n| --- | --- | --- |\n| White powder on nearby furniture | Minerals in the dispersed water settle nearby | The powder alone cannot establish its composition or health effects |\n| Hard white deposits on the tank or parts | Minerals in the water build up inside | Do not assume they are clumps of bacteria |\n| A film on the water surface or slimy contamination inside | Possible microbial growth | Do not treat this as the same phenomenon as white dust |\n\nThe CPSC explains that microorganisms can grow on the surface of deposits. Mineral deposits therefore also need to be removed. Conversely, the absence of white powder does not prove that the humidifier is hygienic. The health effects of white dust cannot be judged by appearance alone either. [CPSC humidifier hygiene guidance](https://www.cpsc.gov/s3fs-public/5046.pdf)\n\n## Choosing water and checking conditions\n\nPractical decisions should consider both the wording in the manual and the current signs of a problem. A purifier's brand alone cannot establish whether its water can be used. The following table applies the principles above to specific situations.\n\n| Current condition | What to consider and check |\n| --- | --- |\n| The manual specifies tap water only | Check with the manufacturer before switching to another type of water |\n| The manual allows distilled water | It can be considered as an option to reduce mineral emissions |\n| The purification method is unknown | First check the purifier model and the substances its filter removes |\n| White powder repeatedly appears nearby | Check both the water's mineral content and the product's permitted water conditions |\n| The tank is slimy or dirty | Do not try to solve it only by changing water types; clean it according to the manual |\n| Tap water is discolored or a water quality notice has been issued | Check the water supplier's guidance before deciding whether to use it |\n\nWhen making an inquiry, provide both the device model name and the water treatment method. You also need to distinguish between powder nearby and deposits inside. The manufacturer needs this information to answer according to the product's requirements.\n\n## What do water replacement and cleaning each address?\n\nReplacing water means emptying out the remaining water. Cleaning means removing contamination attached to internal surfaces. Simply topping up with fresh water cannot replace either task.\n\n\u003e Empty all water from humidifiers every day\n\u003e\n\u003e CDC, Preventing Waterborne Germs at Home\n\nThis means emptying all the water from the device every day. It appears in the CDC's March 15, 2024 guidance. The same guidance also recommends cleaning according to the manufacturer's instructions. It says to let the device air-dry after cleaning. [CDC guidance on water replacement and cleaning](https://www.cdc.gov/drinking-water/prevention/preventing-waterborne-germs-at-home.html)\n\n1. Turn off the power and unplug the device.\n2. Empty the remaining water.\n3. Clean the inside using the method specified in the manual.\n4. If you used a cleaning agent, rinse thoroughly.\n5. Let it dry before storage, or fill it with permitted water just before use.\n\nChemicals used for cleaning are different from additives put in during operation. Running the device with cleaning solution left inside is not a care method. The CPSC requires thorough rinsing to avoid inhaling cleaning chemicals. [CPSC cleaning precautions](https://www.cpsc.gov/s3fs-public/5046.pdf)\n\n## Common mistakes\n\nA common misunderstanding is to treat one characteristic of water as proof of its overall safety. Disinfection and mineral removal are different treatments. Distilled water and boiled and cooled water do not mean the same thing either.\n\n| Common interpretation | Facts to distinguish |\n| --- | --- |\n| It came from a purifier, so it has no minerals | This depends on the purification method and filter performance |\n| It was boiled, so it is the same as distilled water | Distillation requires separately collecting the steam produced |\n| Chlorine in tap water keeps disinfecting the tank | Tap water is not sterile, so replacement and cleaning are necessary |\n| It is a steam humidifier, so it does not need cleaning | The heating mechanism and removal of internal contamination are separate matters |\n| There is no white powder, so it is hygienically clean | The presence or absence of powder cannot establish microbial conditions |\n\nThe CDC also explains the possibility of equipment contamination in the distillation process. It notes that bacteria can grow on cooling components while the equipment is not in use. The name of a treatment method therefore does not guarantee hygiene afterward. [CDC guide to home water treatment methods](https://www.cdc.gov/drinking-water/about/about-home-water-treatment-systems.html)\n\n## Frequently asked questions\n\n### Can you leave water in longer if you use distilled water?\n\nNo. The mineral content of water and the care of standing water are separate matters. Health Canada advises emptying any remaining water when the device is not in use. [Health Canada humidifier care guidance](https://www.canada.ca/en/health-canada/services/household-products/cool-mist-humidifiers.html)\n\n### Can you keep topping up and using a large tank?\n\nA larger capacity does not mean you can skip water replacement. Adding fresh water to what remains is different from replacing all the water. Check the product manual for how often and how to empty it.\n\n### If you choose the right water, can you ignore indoor humidity?\n\nWater choice and indoor humidity control are separate matters. The EPA's June 2022 guidance recommends avoiding humidification to a relative humidity of more than 50%. If condensation forms on windows or the surrounding area gets wet, reduce the humidification output. [EPA indoor humidity guidance](https://www.epa.gov/indoor-air-quality-iaq/use-and-care-home-humidifiers)\n\n### What should you check if the manual gives no water requirements?\n\nAsk the manufacturer's customer support which water quality is permitted for your model. Also tell them how the water you plan to use is treated. An answer for another product may not apply directly.","content_html":"\u003cp\u003eChoose water for a humidifier based on what the product manual specifies. Water from a purifier also varies in mineral content depending on the treatment method. Ultrasonic humidifiers can disperse substances in the water into the air. Whatever water you use, you still need to change it and clean the tank.\u003c/p\u003e\n\u003cp\u003eThe water replacement schedule is based on the CDC's March 15, 2024 guidance.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#what-water-should-you-use\" class=\"anchor\" id=\"what-water-should-you-use\"\u003e\u003c/a\u003eWhat water should you use?\u003c/h2\u003e\n\u003cp\u003eCheck the water requirements in your model's manual to find out which water you can use. The name of the water alone does not tell you whether it suits every product. Read both the manufacturer's conditions for product use and public health agencies' care recommendations.\u003c/p\u003e\n\u003cp\u003eIRIS OHYAMA specifies tap water in its FAQ. It cites the suppression of microbial growth by residual chlorine as the reason. It advises against using water from a purifier or similar sources. This is that manufacturer's guidance, not a rule for all products. \u003ca href=\"https://www.irisohyama.co.jp/support/faq/detail.php?ID=442\"\u003eIRIS OHYAMA water supply FAQ\u003c/a\u003e\u003c/p\u003e\n\u003cp\u003eBy contrast, the EPA, the United States Environmental Protection Agency, recommends water with a low mineral content. The aim is to reduce mineral emissions from ultrasonic and similar humidifiers. You should therefore not switch to distilled water on your own if your product specifies tap water. If the instructions conflict, check with the manufacturer using your model name. \u003ca href=\"https://www.epa.gov/indoor-air-quality-iaq/use-and-care-home-humidifiers\"\u003eEPA guidance on using and caring for home humidifiers\u003c/a\u003e\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#comparing-ultrasonic-steam-and-evaporative-humidifiers\" class=\"anchor\" id=\"comparing-ultrasonic-steam-and-evaporative-humidifiers\"\u003e\u003c/a\u003eComparing ultrasonic, steam, and evaporative humidifiers\u003c/h2\u003e\n\u003cp\u003eHow substances in water move into the air depends on the humidification method. These devices add moisture to the air to raise indoor humidity. Methods that release water droplets must be distinguished from those that evaporate water.\u003c/p\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eType\u003c/th\u003e\n\u003cth\u003eHow it releases moisture\u003c/th\u003e\n\u003cth\u003eWater and care considerations\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Type\"\u003eUltrasonic\u003c/td\u003e\n\u003ctd data-label=\"How it releases moisture\"\u003eUses vibration to create fine water droplets\u003c/td\u003e\n\u003ctd data-label=\"Water and care considerations\"\u003eMinerals and microorganisms in the water can be dispersed along with the droplets\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Type\"\u003eSteam\u003c/td\u003e\n\u003ctd data-label=\"How it releases moisture\"\u003eHeats water to produce water vapor\u003c/td\u003e\n\u003ctd data-label=\"Water and care considerations\"\u003eBe careful of burns from hot water and steam\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Type\"\u003eEvaporative\u003c/td\u003e\n\u003ctd data-label=\"How it releases moisture\"\u003ePasses air through a wet filter or similar material to evaporate water\u003c/td\u003e\n\u003ctd data-label=\"Water and care considerations\"\u003eFilters and areas where water collects need care\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eThe EPA explains that steam and evaporative humidifiers release fewer minerals. This does not mean they need no internal care. For hybrid models, check the actual humidification mechanism rather than relying on the name. \u003ca href=\"https://www.epa.gov/system/files/documents/2022-07/Use%20and%20Care%20of%20Home%20Humidifiers.pdf\"\u003eEPA explanation of humidifier types\u003c/a\u003e\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#comparing-tap-purified-bottled-and-distilled-water\" class=\"anchor\" id=\"comparing-tap-purified-bottled-and-distilled-water\"\u003e\u003c/a\u003eComparing tap, purified, bottled, and distilled water\u003c/h2\u003e\n\u003cp\u003eThe treatment method provides a more specific basis for judgment than the name under which water is sold. The word “purified” does not mean that minerals have been removed. The CDC explains that different filters remove different substances. Check the purifier manual and filter labeling for actual performance.\u003c/p\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eType of water\u003c/th\u003e\n\u003cth\u003eDistinguishing characteristics\u003c/th\u003e\n\u003cth\u003eWhat to check before filling\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Type of water\"\u003eTap water\u003c/td\u003e\n\u003ctd data-label=\"Distinguishing characteristics\"\u003eNot sterile even if it meets drinking water standards\u003c/td\u003e\n\u003ctd data-label=\"What to check before filling\"\u003eWhether the product allows its use and any local water quality notices\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Type of water\"\u003eWater treated with activated carbon\u003c/td\u003e\n\u003ctd data-label=\"Distinguishing characteristics\"\u003eMainly used to improve taste and odor\u003c/td\u003e\n\u003ctd data-label=\"What to check before filling\"\u003eWhether mineral removal performance is separately specified\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Type of water\"\u003eWater treated by reverse osmosis\u003c/td\u003e\n\u003ctd data-label=\"Distinguishing characteristics\"\u003eUses a membrane to reduce dissolved substances\u003c/td\u003e\n\u003ctd data-label=\"What to check before filling\"\u003eThe substances actually removed, such as calcium and magnesium\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Type of water\"\u003eBottled water\u003c/td\u003e\n\u003ctd data-label=\"Distinguishing characteristics\"\u003eBeing bottled does not mean it is low in minerals\u003c/td\u003e\n\u003ctd data-label=\"What to check before filling\"\u003eThe mineral content label and whether the manufacturer allows its use\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Type of water\"\u003eDistilled water\u003c/td\u003e\n\u003ctd data-label=\"Distinguishing characteristics\"\u003eMade by collecting steam from boiling water and turning it back into liquid\u003c/td\u003e\n\u003ctd data-label=\"What to check before filling\"\u003eWhether the product allows its use and whether it contains additives\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Type of water\"\u003eBoiled and cooled water\u003c/td\u003e\n\u003ctd data-label=\"Distinguishing characteristics\"\u003eWater that has been heated and then left to cool\u003c/td\u003e\n\u003ctd data-label=\"What to check before filling\"\u003eDo not treat it as equivalent to distilled water\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eReverse osmosis is a water purification method also called RO. The CDC explains that this method can reduce calcium, magnesium, and other substances. However, the removal performance of each product needs to be checked. Purifier filter replacement also needs attention. \u003ca href=\"https://www.cdc.gov/drinking-water/prevention/about-choosing-home-water-filters.html\"\u003eCDC guide to home water filters\u003c/a\u003e\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#why-do-standards-differ-for-drinking-water-and-water-dispersed-as-mist\" class=\"anchor\" id=\"why-do-standards-differ-for-drinking-water-and-water-dispersed-as-mist\"\u003e\u003c/a\u003eWhy do standards differ for drinking water and water dispersed as mist?\u003c/h2\u003e\n\u003cp\u003eBeing safe to drink does not by itself establish suitability for misting. Swallowing water and inhaling fine water droplets are different. The CDC also explains that drinkable tap water is not sterile. This distinction is often overlooked when choosing water. \u003ca href=\"https://www.cdc.gov/drinking-water/prevention/preventing-waterborne-germs-at-home.html\"\u003eCDC guidance on preventing waterborne germs at home\u003c/a\u003e\u003c/p\u003e\n\u003cp\u003eThe following criteria address different issues.\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003eDrinking suitability concerns whether water can be used for drinking.\u003c/li\u003e\n\u003cli\u003eMineral content is related to the formation of white dust and hard deposits.\u003c/li\u003e\n\u003cli\u003eMicrobial control includes water storage and device cleaning.\u003c/li\u003e\n\u003cli\u003eProduct compatibility concerns the water supply conditions allowed by the manufacturer.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eBottled water is therefore not better suited to filling a humidifier simply because it costs more. Nor does using purified water remove the need to care for the tank. Meeting one criterion does not mean that the other conditions have been met.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#how-do-white-dust-and-deposits-inside-the-tank-differ\" class=\"anchor\" id=\"how-do-white-dust-and-deposits-inside-the-tank-differ\"\u003e\u003c/a\u003eHow do white dust and deposits inside the tank differ?\u003c/h2\u003e\n\u003cp\u003eWhite dust that settles nearby must be distinguished from deposits that adhere to the tank. The CPSC, the United States Consumer Product Safety Commission, explains the two phenomena separately. Even when the same minerals in the water are involved, they appear in different places.\u003c/p\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eWhat you observe\u003c/th\u003e\n\u003cth\u003ePossible cause\u003c/th\u003e\n\u003cth\u003eCautions when interpreting it\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"What you observe\"\u003eWhite powder on nearby furniture\u003c/td\u003e\n\u003ctd data-label=\"Possible cause\"\u003eMinerals in the dispersed water settle nearby\u003c/td\u003e\n\u003ctd data-label=\"Cautions when interpreting it\"\u003eThe powder alone cannot establish its composition or health effects\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"What you observe\"\u003eHard white deposits on the tank or parts\u003c/td\u003e\n\u003ctd data-label=\"Possible cause\"\u003eMinerals in the water build up inside\u003c/td\u003e\n\u003ctd data-label=\"Cautions when interpreting it\"\u003eDo not assume they are clumps of bacteria\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"What you observe\"\u003eA film on the water surface or slimy contamination inside\u003c/td\u003e\n\u003ctd data-label=\"Possible cause\"\u003ePossible microbial growth\u003c/td\u003e\n\u003ctd data-label=\"Cautions when interpreting it\"\u003eDo not treat this as the same phenomenon as white dust\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eThe CPSC explains that microorganisms can grow on the surface of deposits. Mineral deposits therefore also need to be removed. Conversely, the absence of white powder does not prove that the humidifier is hygienic. The health effects of white dust cannot be judged by appearance alone either. \u003ca href=\"https://www.cpsc.gov/s3fs-public/5046.pdf\"\u003eCPSC humidifier hygiene guidance\u003c/a\u003e\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#choosing-water-and-checking-conditions\" class=\"anchor\" id=\"choosing-water-and-checking-conditions\"\u003e\u003c/a\u003eChoosing water and checking conditions\u003c/h2\u003e\n\u003cp\u003ePractical decisions should consider both the wording in the manual and the current signs of a problem. A purifier's brand alone cannot establish whether its water can be used. The following table applies the principles above to specific situations.\u003c/p\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eCurrent condition\u003c/th\u003e\n\u003cth\u003eWhat to consider and check\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Current condition\"\u003eThe manual specifies tap water only\u003c/td\u003e\n\u003ctd data-label=\"What to consider and check\"\u003eCheck with the manufacturer before switching to another type of water\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Current condition\"\u003eThe manual allows distilled water\u003c/td\u003e\n\u003ctd data-label=\"What to consider and check\"\u003eIt can be considered as an option to reduce mineral emissions\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Current condition\"\u003eThe purification method is unknown\u003c/td\u003e\n\u003ctd data-label=\"What to consider and check\"\u003eFirst check the purifier model and the substances its filter removes\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Current condition\"\u003eWhite powder repeatedly appears nearby\u003c/td\u003e\n\u003ctd data-label=\"What to consider and check\"\u003eCheck both the water's mineral content and the product's permitted water conditions\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Current condition\"\u003eThe tank is slimy or dirty\u003c/td\u003e\n\u003ctd data-label=\"What to consider and check\"\u003eDo not try to solve it only by changing water types; clean it according to the manual\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Current condition\"\u003eTap water is discolored or a water quality notice has been issued\u003c/td\u003e\n\u003ctd data-label=\"What to consider and check\"\u003eCheck the water supplier's guidance before deciding whether to use it\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eWhen making an inquiry, provide both the device model name and the water treatment method. You also need to distinguish between powder nearby and deposits inside. The manufacturer needs this information to answer according to the product's requirements.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#what-do-water-replacement-and-cleaning-each-address\" class=\"anchor\" id=\"what-do-water-replacement-and-cleaning-each-address\"\u003e\u003c/a\u003eWhat do water replacement and cleaning each address?\u003c/h2\u003e\n\u003cp\u003eReplacing water means emptying out the remaining water. Cleaning means removing contamination attached to internal surfaces. Simply topping up with fresh water cannot replace either task.\u003c/p\u003e\n\u003cblockquote\u003e\n\u003cp\u003eEmpty all water from humidifiers every day\u003c/p\u003e\n\u003cp\u003eCDC, Preventing Waterborne Germs at Home\u003c/p\u003e\n\u003c/blockquote\u003e\n\u003cp\u003eThis means emptying all the water from the device every day. It appears in the CDC's March 15, 2024 guidance. The same guidance also recommends cleaning according to the manufacturer's instructions. It says to let the device air-dry after cleaning. \u003ca href=\"https://www.cdc.gov/drinking-water/prevention/preventing-waterborne-germs-at-home.html\"\u003eCDC guidance on water replacement and cleaning\u003c/a\u003e\u003c/p\u003e\n\u003col\u003e\n\u003cli\u003eTurn off the power and unplug the device.\u003c/li\u003e\n\u003cli\u003eEmpty the remaining water.\u003c/li\u003e\n\u003cli\u003eClean the inside using the method specified in the manual.\u003c/li\u003e\n\u003cli\u003eIf you used a cleaning agent, rinse thoroughly.\u003c/li\u003e\n\u003cli\u003eLet it dry before storage, or fill it with permitted water just before use.\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003eChemicals used for cleaning are different from additives put in during operation. Running the device with cleaning solution left inside is not a care method. The CPSC requires thorough rinsing to avoid inhaling cleaning chemicals. \u003ca href=\"https://www.cpsc.gov/s3fs-public/5046.pdf\"\u003eCPSC cleaning precautions\u003c/a\u003e\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#common-mistakes\" class=\"anchor\" id=\"common-mistakes\"\u003e\u003c/a\u003eCommon mistakes\u003c/h2\u003e\n\u003cp\u003eA common misunderstanding is to treat one characteristic of water as proof of its overall safety. Disinfection and mineral removal are different treatments. Distilled water and boiled and cooled water do not mean the same thing either.\u003c/p\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eCommon interpretation\u003c/th\u003e\n\u003cth\u003eFacts to distinguish\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Common interpretation\"\u003eIt came from a purifier, so it has no minerals\u003c/td\u003e\n\u003ctd data-label=\"Facts to distinguish\"\u003eThis depends on the purification method and filter performance\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Common interpretation\"\u003eIt was boiled, so it is the same as distilled water\u003c/td\u003e\n\u003ctd data-label=\"Facts to distinguish\"\u003eDistillation requires separately collecting the steam produced\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Common interpretation\"\u003eChlorine in tap water keeps disinfecting the tank\u003c/td\u003e\n\u003ctd data-label=\"Facts to distinguish\"\u003eTap water is not sterile, so replacement and cleaning are necessary\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Common interpretation\"\u003eIt is a steam humidifier, so it does not need cleaning\u003c/td\u003e\n\u003ctd data-label=\"Facts to distinguish\"\u003eThe heating mechanism and removal of internal contamination are separate matters\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Common interpretation\"\u003eThere is no white powder, so it is hygienically clean\u003c/td\u003e\n\u003ctd data-label=\"Facts to distinguish\"\u003eThe presence or absence of powder cannot establish microbial conditions\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eThe CDC also explains the possibility of equipment contamination in the distillation process. It notes that bacteria can grow on cooling components while the equipment is not in use. The name of a treatment method therefore does not guarantee hygiene afterward. \u003ca href=\"https://www.cdc.gov/drinking-water/about/about-home-water-treatment-systems.html\"\u003eCDC guide to home water treatment methods\u003c/a\u003e\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#frequently-asked-questions\" class=\"anchor\" id=\"frequently-asked-questions\"\u003e\u003c/a\u003eFrequently asked questions\u003c/h2\u003e\n\u003ch3\u003e\n\u003ca href=\"#can-you-leave-water-in-longer-if-you-use-distilled-water\" class=\"anchor\" id=\"can-you-leave-water-in-longer-if-you-use-distilled-water\"\u003e\u003c/a\u003eCan you leave water in longer if you use distilled water?\u003c/h3\u003e\n\u003cp\u003eNo. The mineral content of water and the care of standing water are separate matters. Health Canada advises emptying any remaining water when the device is not in use. \u003ca href=\"https://www.canada.ca/en/health-canada/services/household-products/cool-mist-humidifiers.html\"\u003eHealth Canada humidifier care guidance\u003c/a\u003e\u003c/p\u003e\n\u003ch3\u003e\n\u003ca href=\"#can-you-keep-topping-up-and-using-a-large-tank\" class=\"anchor\" id=\"can-you-keep-topping-up-and-using-a-large-tank\"\u003e\u003c/a\u003eCan you keep topping up and using a large tank?\u003c/h3\u003e\n\u003cp\u003eA larger capacity does not mean you can skip water replacement. Adding fresh water to what remains is different from replacing all the water. Check the product manual for how often and how to empty it.\u003c/p\u003e\n\u003ch3\u003e\n\u003ca href=\"#if-you-choose-the-right-water-can-you-ignore-indoor-humidity\" class=\"anchor\" id=\"if-you-choose-the-right-water-can-you-ignore-indoor-humidity\"\u003e\u003c/a\u003eIf you choose the right water, can you ignore indoor humidity?\u003c/h3\u003e\n\u003cp\u003eWater choice and indoor humidity control are separate matters. The EPA's June 2022 guidance recommends avoiding humidification to a relative humidity of more than 50%. If condensation forms on windows or the surrounding area gets wet, reduce the humidification output. \u003ca href=\"https://www.epa.gov/indoor-air-quality-iaq/use-and-care-home-humidifiers\"\u003eEPA indoor humidity guidance\u003c/a\u003e\u003c/p\u003e\n\u003ch3\u003e\n\u003ca href=\"#what-should-you-check-if-the-manual-gives-no-water-requirements\" class=\"anchor\" id=\"what-should-you-check-if-the-manual-gives-no-water-requirements\"\u003e\u003c/a\u003eWhat should you check if the manual gives no water requirements?\u003c/h3\u003e\n\u003cp\u003eAsk the manufacturer's customer support which water quality is permitted for your model. Also tell them how the water you plan to use is treated. An answer for another product may not apply directly.\u003c/p\u003e\n","tags":["Bottled water","Household essentials","Humidifier"],"faqs":[{"question":"Can I use tap water?","answer":"It depends on whether the product manual allows or specifies it. Some manufacturers specify tap water, but public agencies also offer recommendations aimed at reducing mineral emissions from ultrasonic models. It is difficult to apply one answer to every product."},{"question":"Does filtered water have all its minerals removed?","answer":"No. What gets removed depends on the treatment method, such as activated carbon or reverse osmosis. Check the water purifier's manual and the filter's performance information."},{"question":"Is bottled water more suitable than tap water for filling the device?","answer":"You cannot judge by the label “bottled water” alone. Bottled water can also contain minerals. Check both the product's water requirements and the water's listed composition."},{"question":"Is water that has been boiled and cooled distilled water?","answer":"No. Distilled water is made by boiling water, collecting the steam separately, and condensing it into liquid. It is different from water that has been boiled and cooled in its original container."},{"question":"Is the white powder around the device bacteria?","answer":"It may be white dust left by minerals in the mist settling on surrounding surfaces. Appearance alone cannot establish whether bacteria are present or determine the exact composition."},{"question":"Are hard white deposits inside the water tank evidence of a malfunction?","answer":"They may be accumulated mineral deposits, so they do not indicate a malfunction on their own. They need to be removed according to the manual. If the device also operates abnormally, check the manufacturer's inspection criteria."},{"question":"Can I skip cleaning if I use distilled water?","answer":"No. Reducing minerals and removing contamination from the water tank are separate matters. Water changes and cleaning are still necessary."},{"question":"If there is water left, can I just top it up with fresh water?","answer":"Topping up does not replace a complete water change. CDC's guidance dated March 15, 2024, recommends emptying all the water from portable models every day."},{"question":"Do heated models require no internal maintenance?","answer":"Heated models also need maintenance according to the manufacturer's instructions. The fact that they work by heating water does not replace the need to remove internal deposits."},{"question":"What should I follow if the manual and answers online differ?","answer":"Check the manual for the specific model's conditions of use. Ask the manufacturer about any points that conflict with public agency recommendations. Do not apply answers about other models directly to yours."}],"sources":[{"url":"https://www.epa.gov/indoor-air-quality-iaq/use-and-care-home-humidifiers","title":"EPA, Use and Care of Home Humidifiers","type":"source"},{"url":"https://www.epa.gov/system/files/documents/2022-07/Use%20and%20Care%20of%20Home%20Humidifiers.pdf","title":"EPA, Use and Care of Home Humidifiers, revised June 2022","type":"source"},{"url":"https://www.cdc.gov/drinking-water/prevention/preventing-waterborne-germs-at-home.html","title":"CDC, Preventing Waterborne Germs at Home, March 15, 2024","type":"source"},{"url":"https://www.cdc.gov/drinking-water/prevention/about-choosing-home-water-filters.html","title":"CDC, About Choosing Home Water Filters, April 10, 2024","type":"source"},{"url":"https://www.cdc.gov/drinking-water/about/about-home-water-treatment-systems.html","title":"CDC, About Home Water Treatment Systems, April 10, 2024","type":"source"},{"url":"https://www.irisohyama.co.jp/support/faq/detail.php?ID=442","title":"IRIS OHYAMA, FAQ on whether water other than tap water can be used in humidifiers","type":"source"},{"url":"https://www.cpsc.gov/s3fs-public/5046.pdf","title":"CPSC, Dirty Humidifiers May Cause Health Problems","type":"source"},{"url":"https://www.canada.ca/en/health-canada/services/household-products/cool-mist-humidifiers.html","title":"Health Canada, Cool-mist humidifiers, December 6, 2016","type":"source"}],"images":[{"id":2292,"url":"https://injoys.com/rails/active_storage/blobs/proxy/eyJfcmFpbHMiOnsiZGF0YSI6MzUxODQsInB1ciI6ImJsb2JfaWQifX0=--2b4259d69b972706fa582e0217c7cfe51d6ef4c4/ai-8769991b.webp","is_representative":true,"generation_method":"ai_photo","license":"ai_generated","mime_type":"image/webp","width":1536,"height":1024,"translations":{"ko":{"alt":"청록색 스웨터를 입은 남성이 주방 싱크대 옆에서 투명한 물병으로 가습기 수조에 물을 붓고 있다.","caption":"사용할 물은 제품 설명서에 명시된 모델별 급수 조건에 따라 선택해야 한다.","description":null},"en":{"alt":"A man in a teal sweater pours water from a clear jug into an open humidifier tank beside a kitchen sink.","caption":"Choose water according to the filling requirements specified in the manual for your model.","description":null},"ja":{"alt":"青緑色のセーターを着た男性が、台所のシンク脇で透明なピッチャーから加湿器のタンクに水を注いでいる。","caption":"使用する水は、取扱説明書に記載された機種ごとの給水条件に従って選ぶ必要がある。","description":null},"es":{"alt":"Un hombre vierte agua de una jarra transparente en el depósito abierto de un humidificador junto al fregadero.","caption":"El agua debe elegirse según los requisitos de llenado indicados en el manual de cada modelo.","description":null},"id":{"alt":"Seorang pria menuangkan air dari teko bening ke tangki pelembap udara yang terbuka di samping bak cuci dapur.","caption":"Pilih air sesuai ketentuan pengisian yang tercantum dalam buku petunjuk untuk model yang digunakan.","description":null},"pt":{"alt":"Um homem despeja água de uma jarra transparente no reservatório aberto de um umidificador ao lado da pia.","caption":"A água deve ser escolhida conforme os requisitos de abastecimento indicados no manual de cada modelo.","description":null},"zh-hant":{"alt":"一名穿著藍綠色毛衣的男子在廚房水槽旁，用透明水壺將水倒入敞開的加濕器水箱。","caption":"應依照產品說明書中各型號的加水條件，選擇適用的水。","description":null},"de":{"alt":"Ein Mann gießt neben der Küchenspüle Wasser aus einem klaren Krug in den offenen Tank eines Luftbefeuchters.","caption":"Die Wasserwahl muss sich nach den Befüllvorgaben in der Bedienungsanleitung des jeweiligen Modells richten.","description":null}}},{"id":2293,"url":"https://injoys.com/rails/active_storage/blobs/proxy/eyJfcmFpbHMiOnsiZGF0YSI6MzUxOTAsInB1ciI6ImJsb2JfaWQifX0=--e40dcdc5290d6f7663f83255e2ccc91a4486c6cb/ai-bbc8909f.webp","is_representative":false,"generation_method":"ai_semi","license":"ai_generated","mime_type":"image/webp","width":1536,"height":1024,"translations":{"ko":{"alt":"자주색 스웨터를 입은 여성이 가습기 옆 짙은 나무 수납장 위에 쌓인 흰 가루를 살펴본다.","caption":"주변의 백분과 수조 내부의 단단한 침전물은 발생 위치를 구분해 살펴야 한다.","description":null},"en":{"alt":"A woman in a plum sweater examines white powder on a dark wooden cabinet beside a humidifier.","caption":"White dust on nearby surfaces should be distinguished from hard deposits inside the tank.","description":null},"ja":{"alt":"紫色のセーターを着た女性が、加湿器の横の濃い色の木製キャビネットに積もった白い粉を確かめている。","caption":"周囲に付く白い粉とタンク内の硬い沈着物は、発生する場所を区別して確認する必要がある。","description":null},"es":{"alt":"Una mujer con un suéter morado examina polvo blanco sobre un mueble de madera junto a un humidificador.","caption":"El polvo blanco en las superficies cercanas debe distinguirse de los depósitos duros dentro del tanque.","description":null},"id":{"alt":"Perempuan bersweater ungu mengamati serbuk putih di atas lemari kayu gelap di samping pelembap udara.","caption":"Serbuk putih di permukaan sekitar perlu dibedakan dari endapan keras di dalam tangki.","description":null},"pt":{"alt":"Uma mulher de suéter roxo examina pó branco sobre um móvel de madeira escura ao lado de um umidificador.","caption":"O pó branco nas superfícies próximas deve ser diferenciado dos depósitos duros dentro do reservatório.","description":null},"zh-hant":{"alt":"一名穿著紫紅色毛衣的女子，查看加濕器旁深色木櫃表面堆積的白色粉末。","caption":"周圍表面的白色粉末與水箱內的堅硬沉積物，應依出現位置加以區分。","description":null},"de":{"alt":"Eine Frau im violetten Pullover prüft weißes Pulver auf einem dunklen Holzschrank neben einem Luftbefeuchter.","caption":"Weißer Staub auf umliegenden Flächen ist von harten Ablagerungen im Tank zu unterscheiden.","description":null}}}],"published_at":"2026-10-31T05:08:07+09:00","updated_at":"2026-10-31T05:08:07+09:00","license":"cc_by","translation_status":"reviewed","available_locales":["ko","en","ja","es"],"data_locales":["ko","en","ja","es","id","pt","zh-hant","de"],"url":"https://injoys.com/en/articles/humidifier-water-tap-filtered-distilled-guide"}