Why do so many Japanese wear masks?

Many Japanese people have the impression that many people wear masks, and one of the causes is hay fever.

The amount of airborne pollen is expected to be “low” from Kyushu to Tohoku through Friday, the 21st.

Rain and snow are expected to fall from Kyushu to Kanto until morning, and from Hokuriku and Tohoku until around noon, but the weather is expected to gradually improve. Although the amount of airborne pollen is expected to be low, pollen will be more likely to fly after the rain, so be on your guard and take precautions.

From Monday this week, the winter pressure pattern is expected to intensify and strong cold air is expected to flow into the sky. This cold air will stay for about a week, and there is a possibility of blizzards and heavy snow on the Sea of Japan side, and snow will fall mainly along the mountains on the Pacific side. Even when the weather is clear, northerly winds will be strong and it will remain bitterly cold, especially in the mornings and evenings.

After the cold wave clears, temperatures will rise, and there is a risk of a sudden increase in the amount of pollen dispersal around Tuesday, the 25th, so caution is advised.

There are three main conditions that cause pollen to fly easily.

(1) Sunny days with high temperatures.

Male cedar flowers open more easily when the temperature rises. In addition, sunny days with high temperatures tend to generate an updraft, which makes it easier for pollen to fly up, thus increasing the amount of pollen dispersed.

(2) Days when the air is dry and windy

When the air is humid, pollen absorbs moisture and becomes heavier, making it harder to fly far. On the other hand, on days when the air is dry and windy, pollen is more likely to be carried from forests far from urban areas.

(3) After the day after rain or after several days of high temperatures.

Pollen that was not dispersed on rainy days tends to fly in clusters on and after the next day, resulting in an increase in the amount of pollen dispersed. In addition, pollen that fell to the ground due to rain may be blown up again, so care should be taken. Pollen dispersal also tends to increase after two or three days of high temperatures.

Avoiding pollen is an important way to relieve hay fever symptoms. 

(1) Wear glasses

Simply wearing glasses can reduce the amount of pollen that enters the eyes by about 40%. In addition, experiments have shown that hay fever prevention glasses with protective covers can reduce the amount of pollen entering the eyes by about 65%.

(2) Use of masks

Wearing a mask can reduce the amount of pollen inhaled by one-third to one-sixth. It is important to choose a mask that fits tightly to the face. In addition, the use of an “inner mask” with gauze inserted inside the mask can reduce the amount of pollen that enters the nose more effectively.

(3) Clothing

Clothing made of wool adheres more easily to pollen than cotton or synthetic fibers, causing pollen to be brought indoors. In particular, wool is about 10 times more likely to adhere to pollen than cotton. When going outside, avoid clothing made of wool and choose a jacket with a smooth surface to reduce pollen adhesion.

※I rewrote the Japanese article in part and used a translation tool.