Life Hacks in Japan

This is a blog that provides information on good buys, health, money, and other things that enrich your life, as well as your hobbies and interests! (Tap twice to view categories such as "Shopping" in the ↓.)

"Life in Japan 2023" Here is how to choose a humidifier and recommended manufacturers!

Humidifiers are used to maintain humidity, prevent influenza and other illnesses, and for beauty, but if you choose the wrong one, you risk damaging your health. Please understand the key points and select the most appropriate humidifier for your needs.

Dangers of ultrasonic and vaporizing humidifiers

There are three main types of humidifiers.

vaporization type

Airflow over a filter such as a moistened paper.

Steam type

Boil water to produce steam.

ultrasonic formula

Vibrates water to generate a mist. Image of misting


However, ultrasonic humidification is a major cause of a disease called "humidifier lung" and numerous cases have been reported in papers. It is believed that even with proper maintenance, the high risk is likely to remain the same.

Hypersensitivity pneumonitis caused by microorganisms from humidifiers and air conditioning units is known as humidifier lung or air conditioning disease. It is reported to account for 4.3% of all cases of hypersensitivity pneumonitis, and more than 30 cases of humidifier lung cases in Japan have been seen in journal reports alone.


Regarding the humidification method, most of the case reports of humidifier pulmonary disease were of the ultrasonic type.


In addition, the amount of bacteria emitted from the ultrasonic humidifiers was found to be significantly high. In particular, although two of the eight ultrasonic humidifiers were dried after each use and new stored water was drawn, a large amount of viable bacteria was detected in the stored water and the blowing air, suggesting that the risk is high even under proper use.
Microorganisms in Reservoir Water and Blown Air from a Household Humidifier


Similarly, the vaporization type has significant bacterial growth, and if used, it is considered necessary to clean, dry, and sterilize the humidification tray at least once a week.

Many home humidifiers use a suction type (water is sucked into the element by capillary action) vaporizing humidifier, and a significant increase in the number of bacteria in the stored water (106 cfu/mL or more) has been reported. The vaporizing humidifiers examined in this study were found to have a high probability of detecting microorganisms in the air, and microorganisms that had grown in the stored water could also be dispersed into the air. The instruction manuals for all vaporizing humidifiers surveyed stated that the frequency of cleaning should be "every four weeks" or "when the odor becomes bothersome. However, it is known that the number of bacteria in humidifier trays increases over time from the day of operation, reaches maturity on the seventh day, and then reaches a steady state, suggesting that cleaning, drying, and sterilization of humidifier trays should be performed at least once a week, even for vaporizers.
Microorganisms in Reservoir Water and Blown Air from a Household Humidifier


Based on the above results, considering the complexity of maintenance, the "heated humidifier," in which the water supply tank and heating unit are integrated, is considered to be the safest.



air cleaner

The details are written in the following article, but since the paper states that Plasmacluster/Nano-e had no sterilization effect as a result of the experiment, Panasonic and Sharp products with these functions are omitted from the comparison.


Product Comparison Chart

Now, let's begin the comparison. Since low humidity can cause sore throats and high humidity can cause mold and other problems, we will focus our comparison on models with automatic humidity control. As a result, the following points can be checked.

  • Appropriate capacity (size)
  • Safety (burn hazard)
  • Automatic humidity control

Note that if multiple products are sold, the product with the highest functionality and smallest capacity is picked up. (You can scroll to the right.)

Manufacturer Mitsubishi Heavy Industries Toshiba YAMAZEN ZOJIRUSHI
model number SHE35VD KA-X45 KSF-GB40 EE-DC35
Amount of humidification 350mL/h 450mL/h 500mL/h 350mL/h
Supported tatami mats (wooden) 6 8 8.5 6
Supported tatami mats (concrete) 10 13 14 10
capacity 2.8L 4.0L 4.0L 3.0L
aroma × ×
Dimensions W 220 x D 267 x H 245mm (including handle) W 264 x D 257 x H 285mm (including handle) W 255 x D 200 x H 320mm W 240 x D 275 x H 325mm
weight 3.0kg 3.3kg(including code set) 2.4kg 2.7kg
feature Automatic adjustment to humidity according to temperature
Steam at 55°C
Automatic adjustment to humidity according to temperature nothing in particular Steam at 65°C
Price* 9,280 yen - 10,081 yen 19,500 yen

*...prices on Amazon as of December 30, 2022.


Regarding the automatic humidity control function, Yamazen could only adjust the humidity to be between 50 ~ 60%, and Zojirushi only automatically adjusted the humidity to the specified level. However, Mitsubishi Heavy Industries and Toshiba automatically adjust the humidity according to the temperature.

Steam Fan Humidifier|KA-X45/KA-X60-Toshiba Lifestyle Corporation


Also, the steam type's biggest drawback is hot steam, but Mitsubishi Heavy Industries and Zojirushi are made so that the steam is reduced to a temperature that will not burn you.

Due to humidity control and steam safety, our blog recommends Mitsubishi Heavy Industries. We hope the above is helpful.

MHI Product Comparison Chart

model number SHE35VD SHE60VD SHE120VD
Amount of humidification 350mL/h 600mL/h 1,200mL/h
Supported tatami mats (wooden) 6 10 20
Supported tatami mats (concrete) 10 17 33
capacity 2.8L 4L 5L×2
Dimensions (including handle) W 220 x D 267 x H 245mm W 221 x D 297 x H 308mm W 440 x D 290 x H 320mm
weight 3.0kg 4.0kg 8.0kg