[Click! Health] Air Conditioner Use in Hot Weather Causes 'Naengbangbyeong'... How to Prevent It?

Due to the ongoing heatwave, the use of air conditioning devices day and night is becoming more common. However, caution is needed as so-called air conditioning sickness can occur when there is a large temperature difference between indoors and outdoors and indoor humidity drops.

Air conditioning sickness is not an official medical term. It can be understood as various illnesses caused by air conditioning used indoors during hot summer months. Our bodies adapt well to temperature changes, enduring cold in winter and high temperatures in summer. However, when the temperature difference between indoors and outdoors exceeds 5 degrees Celsius, the autonomic nervous system struggles to adjust to the changed temperature, leading to symptoms of air conditioning sickness. If exposed for a long time to a situation where the outdoor temperature is high but the indoor temperature is excessively low, the body cannot adapt to the temperature difference, resulting in illness. Continuous operation of air conditioners also lowers indoor humidity, which can cause dryness of the respiratory mucous membranes and cold symptoms accompanied by coughing.

Rarely, infection with Legionella bacteria can cause symptoms of air conditioning sickness. Legionella bacteria thrive in the cooling water used in large building air conditioning systems and can be released into the air when the air conditioner operates, causing infection. Infection by Legionella bacteria shows symptoms similar to a cold, such as fever, headache, diarrhea, and muscle pain. Especially elderly people with weakened immune systems or those with chronic diseases are more susceptible to infection, so caution is necessary.

[Photo by Seoul Asan Hospital]

Professor Lee Jeong-ah of the Department of Family Medicine at Seoul Asan Medical Center advised, "The most important thing to stay healthy during summer without air conditioning sickness is to reduce the temperature difference between indoors and outdoors." She added, "When the temperature difference exceeds 5 degrees, our bodies find it difficult to respond appropriately to the changed temperature, so it is best to maintain the proper indoor temperature of 24 to 26 degrees Celsius during summer and adjust the indoor temperature according to the outdoor temperature to minimize the difference."

The next important measure is regular ventilation. Many people keep windows closed all day to maintain a cool indoor temperature with air conditioning, but this causes various harmful substances to accumulate indoors continuously. Chemical components emitted from furniture, carpets, paints or adhesives used in building construction, copiers, and electronic devices cannot escape outside and fill the indoor air. Even if it is a bit hot, windows should be opened regularly for natural ventilation. If you are in a high-rise building or an environment where windows cannot be opened, properly operating a central ventilation system can also help. Ventilation is essential for maintaining appropriate humidity as well. Running the air conditioner for about an hour can lower humidity to 30-40%, so it is good to open windows frequently to ventilate and maintain proper indoor humidity.

Cleaning air conditioners is also important. To prevent Legionella bacteria that cause pneumonia and other illnesses, air conditioners should always be kept clean. When turning on the air conditioner for the first time after a year, it must be cleaned, and internal filters, where bacteria and mold easily grow, should be cleaned at least once every two weeks.

Consuming cold foods or drinks too frequently because of the heat can also create a body condition prone to air conditioning sickness. On the other hand, sufficient hydration helps prevent air conditioning sickness, so if you have to work indoors with air conditioning for a long time, it is good to frequently drink warm beverages to replenish fluids and keep your body warm by wearing thin long-sleeved clothing.