I would actually like to pay more attention to absolute humidity than relative humidity...

Proper management of humidity is important for humans to live healthily.
If it's over 80%, mold will grow easily, and if it's below 40%,
Viruses and other diseases become more easily transmitted. For ticks, the infection rate exceeds 50%.
It becomes easier to get them, but it starts to increase in earnest when it exceeds 60%.
From
Based on these indicators, it has often been said that the ideal indoor relative humidity is 40% to 60%.
However, in reality, a comfortable room temperature is best maintained at 40% in winter and 60% in summer.
I think it's finally here.
However, this relative humidity is quite tricky.
As I wrote in my blog just the other day, first of all, there is a huge amount of error depending on the machine.
All the hygrometers around me fluctuate by around 15% even under the same conditions.
Even if you have an accurate hygrometer, if there is a temperature difference between the top and bottom, the height at which you install it will be
Therefore, the relative humidity can change significantly. It is not uncommon for it to change by around 10%.
However, it is absolute humidity that is actually more closely related to human physiological phenomena.
This is how many grams of water per cubic meter or kilogram of air.
This indicates how much of the food is being consumed. If it is winter in Japan, it may be less than 5g.
This is not uncommon, and in the summer it can exceed 20g.
However, medical standards state that influenza is generally more contagious at doses of 9g/kg (11g/cubic meter) or less.
There are research results from around the world. The mucous membrane of the throat begins to dry out at less than 9g/kg.
This is written in the book "Humidity and Humans". The reason these two numbers are the same is because the mucous membrane
Dryness may mean your body is less resistant to viruses.
By the way, the Mitsubishi humidifier has a "throat" mode that maintains 9g.
There are some things attached.
However, this 9g is quite a tricky thing, according to my acquaintance, probably the most famous in Japan.
I learned from Mr. H, an ordinary person who is knowledgeable about thermal environments. The reason for maintaining 9g in winter is actually
It's quite difficult. If the room temperature is 20°C, 61.6% is required. By the way, if the room temperature is 18°C,
69.7% is required.
This overlaps with the habitat of the ticks mentioned above.
Mr. H seemed to have thought about this, and based on a survey of his family and friends, he found that absolute humidity should be below a certain level.
Apparently they conducted a survey to see if people felt thirsty, and the result was 7g.
I will try calculating again using 7g.
21℃ 45.1%
20℃ 48.0%
19℃ 51.1%
18℃ 54.4%
.
I don't recommend indoor temperatures below this, so I won't write about it here, but it's the UK definition of healthy
The temperature is over 21 degrees Celsius, so from this we can see that the temperature is 21 degrees Celsius and the relative humidity is 45%.
This could be said to be the ultimate goal for winter.
I would like to look at this from a different perspective.
To achieve both 80% and 7g absolute humidity, at which point mold begins to grow, what temperature must the room temperature be?
Is it possible?
If you do the math, you'll need a temperature of at least 12 degrees Celsius.
So, let's say we set it at 60%, the level at which mites start to multiply in earnest.
A temperature of 17°C or higher is required.
Thinking about it this way, "while maintaining an ideal humidity environment
In order to prevent mold from coexisting, the room temperature needs to be above 12 degrees Celsius.
"To maintain an ideal humidity environment while avoiding coexistence with mites,
The room temperature needs to be above 17 degrees Celsius.
We can also think of it in a paradoxical way.
If you think about it this way, it is possible to achieve an ideal humidity environment while keeping utility bills low.
I think you can see how important and difficult it is.